Browse Articles
Discover research articles across all indexed journals
Nanographene‐Based van der Waals Organic Framework With Permanent Porosity
ABSTRACT Porous crystalline materials traditionally rely on robust coordination or covalent bonds. Herein, we report a new C 3 ‐symmetric molecular nanographene 1 containing three hexabenzocoronene (HBC) units that self‐organizes into a permanently porous framework exclusively using weak van der Waals interactions. Single‐crystal x‐ray diffraction results reveal a propeller geometry with C 3 symmetry, forming two‐dimensional honeycomb sheets parallel to the ab plane stabilized by π···π and C–H···π interactions. Nitrogen adsorption measurements at 77 K confirm a Type I(b) isotherm with a record‐breaking Brunauer–Emmett–Teller (BET) surface area of 1108 m 2 g −1 , the highest reported to date for purely organic van der Waals frameworks. Furthermore, compound 1 exhibits aggregation‐induced emission (AIE) and remarkable thermal stability up to 290° C. These results demonstrate that carefully designed nanographenes can achieve high structural predictability and robust porosity without the need for metal nodes or covalent linkages, opening new avenues for gas storage applications.
Impact of feature engineering on predicting non-contact football injuries
Digital literacy is associated with college students’ learning engagement via sequential mediation of self-efficacy and learning adaptability
Cation-Induced Interphasial Viscosity Variations on Gold Electrocatalysts in Nanoconfined Aqueous Electrolytes
Cytotoxicity and synergistic anticancer activity of Kigelia africana (Lam.) Benth. and Spathodea campanulata P. Beauv. polyherbal extracts
Integration of Fe Single Atoms to Improve Kinetics and Mass Transport in Oxygen Reduction Reaction for Zinc‐Air Batteries
ABSTRACT Simultaneous optimization of intrinsic activity and mass transport to enhance the oxygen reduction reaction (ORR) performance of zinc‐air battery (ZAB) cathodes is crucial yet remains a formidable challenge. In this study, we developed a cross‐scale synergy strategy to embed Fe−N 4 /Fe 3 C active microdomains into a 3D mesopore‐dominated carbon nanoflower framework (Fe SA /Fe 3 C NP @CNF). This approach effectively bridges the microscopic electronic modulation of active sites with the macroscopic regulation of the pore structure of the carbon framework, thus simultaneously improving intrinsic activity and mass transport. The resulting Fe SA /Fe 3 C NP @CNF electrocatalyst exhibits outstanding ORR performance with a half‐wave potential of 0.921 V versus RHE and superior stability. In ZABs, it delivers a high peak power density of 199.1 mW cm −2 and remarkable cycling stability over 500 h. In situ spectroelectrochemical measurements and theoretical calculations reveal that Fe 3 C modulates the electronic structure of Fe−N 4 sites by optimizing Fe 3d orbital occupancy and lowering the energy barrier for oxygen activation. Distribution of relaxation times, zero‐length column chromatography, bubble‐transport dynamics, and finite element simulations collectively demonstrate that the mesopore‐dominated nanoflower architecture promotes rapid oxygen transport and maximizes active‐site accessibility. This study establishes a versatile cross‐scale design principle for developing high‐performance ORR electrocatalysts in practical energy‐conversion devices.
Height-aware attention for industrial defect detection: co-designing imaging and deep networks for rubber–metal bushings
Correction to “DNA-Mediated Cellular Delivery of Functional Enzymes”
Rand transformer net: An efficient network for semantic segmentation of railway engineering entities based on 3D point cloud
HCFL: hybrid contribution-driven federated learning for fair and efficient optimization
Photosynthetic acclimation to abiotic stress in an acidophilic microalga from Tinto River
Strongly Correlated Electron Systems in Triple Metal Atoms Trigger Atomic‐Level Structure Resonance for Durable and Efficient Ammonia Electrosynthesis
ABSTRACT Electrocatalytic nitrate reduction reaction (NO 3 RR) is an important route for achieving both sustainable ammonia synthesis and wastewater treatment. However, the weak electron correlation characteristics between the active sites in traditional catalysts leads to their limited dynamic adaptability, which highly restricts the construction of ammonia synthesis systems that simultaneously possess high selectivity, high yield rate, and high stability. Here, we synthesize a NiCoFeOOH multi‐metallic catalyst with strong electron coupling characteristics by inducing the electron‐spin‐geometric structure transformation via an in situ reconstruction strategy. NiCoFeOOH sustains high Faradaic efficiencies (FEs, 95%–99%) across a broad potential range together with a remarkable yield rate of 52 mg h −1 cm −2 . The catalyst remains stable for up to 324 h at the industrial current density of 1 A cm −2 (FEs ∼ 90%, a record‐breaking yield rate of ∼72 mg h −1 cm −2 ) in a membrane electrode assembly electrolyzer (MEA), ranking it among the most efficient and stable electrocatalysts reported hitherto. Operando/in situ characterizations combined with theoretical calculations show that atomic resonance between triple octahedral structural unit and key intermediate highly mediates the hydrogenation pathway. Based on the quantum spin exchange interaction, the adaptive charge transport channel among multiple atoms accelerates the proton‐coupled electron transfer kinetics and suppress atomic dissolution at ampere‐level current densities.
Using sagittal otolith morphometrics and shape to discriminate three Nemipterus species (Teleostei: Nemipteridae) from Hurghada, Red Sea, Egypt
Abstract Otolith morphology and morphometrics have been widely used to investigate taxonomic distinctions and infer potential relationships among fish species. This study focuses on the sagittal otolith shape and morphological traits of three Nemipterus species ( N. zysron , N. randalli , and N. bipunctatus ), employing size parameters, shape descriptors, Elliptic Fourier Analysis (EFA), and Scanning Electron Microscopy (SEM). Linear relationships were observed between otolith morphometric parameters namely, feret length (OL), feret width (OH), weight (OW), area (OA), and perimeter (OP) and fish biometric traits, including standard length (SL) and body weight (W). Ten shape descriptors, including Circularity (CI), Roundness (RO), and Ellipticity (EL), were evaluated and corrected for size effects. The strongest correlations were noted in OP-OL for N. zysron and N. randalli , and OA-OL for N. bipunctatus Uncorrected descriptors correlated significantly with SL, OL, OH, and OW, whereas corrected descriptors showed mostly non-significant correlations, indicating the effect of size correction. EFA revealed interspecific differences in otolith contour patterns. N. randalli and N. bipunctatus displayed greater morphological similarity, while N. zysron appeared more morphologically distinct. SEM provided detailed structural insights, revealing interspecific differences in the sulcus acusticus , rostrum, and margins, with six unique traits distinguishing N. zysron. This study demonstrates otolith shape analysis as a cost-effective and reliable method for fish species discrimination. These findings underscore the value of otolith-based approaches as alternatives to genetic marker techniques, enhancing taxonomic research.
The chain mediating roles of emotional resilience and posttraumatic growth in the relationship between perceived stress and cognitive flexibility among military recruits
Abstract Military recruits undergo a transition from local youth to qualified soldiers, which subjects them to pressure. Previous research has focused on the relationship between perceived stress and cognitive flexibility; however, researchers have largely overlooked the mediating processes underlying this association, particularly among military recruits. This study aimed to identify the mediating roles played by emotional resilience and posttraumatic growth (PTG) in this relationship. A convenience sampling method was used to select 8509 military recruits from western China. The survey administered to these recruits included a general demographic information questionnaire, the Chinese version of the Perceived Stress Scale (PSS), the Cognitive Flexibility Inventory (CFI), the Emotional Resilience Scale (ERS), and the Post-Traumatic Growth Inventory (PTGI). A mediation analysis was conducted to examine the potential process through which emotional resilience and PTG mediate the relationship between perceived stress and cognitive flexibility. (1) The findings reveal significant correlations among perceived stress, emotional resilience, PTG, and cognitive flexibility. (2) Perceived stress is negatively correlated with cognitive flexibility ( β = -0.32, P < 0.001). Emotional resilience and PTG not only mediate this relationship but also play chain mediating roles in shaping the relationship between perceived stress and cognitive flexibility. Perceived stress is observed to be significantly related to the cognitive flexibility of military recruits. This relationship is mediated by emotional resilience and PTG—both independently and sequentially—on the basis of a chain mediation model. These findings explain the patterns underlying these associations and provide a theoretical reference for interventions aimed at improving cognitive flexibility.
Poly(bromophenol blue)/CoSn(OH)6 cubic particles modified pencil graphite electrode for electrochemical determination of diphenhydramine
Revitalizing Fulleropyrrolidine via Nonionic Sidechain Engineering: An Ethanol‐Processible Interlayer Enabling Efficient Organic Solar Cells
ABSTRACT Organic solar cells (OSCs) advancement hinges critically on cathode interlayer materials (CIMs) that meet multiple requirements: thickness‐insensitivity to facilitate device upscaling, mitigated hydrophilicity to enhance stability, and processability from green solvents to minimize environmental impact and reduce post‐processing costs. We design and synthesize bis‐sulfonimide‐functionalized fulleropyrrolidine derivatives grafted with nonionic sidechains. C60‐BSI‐PS, incorporating phosphonate ester sidechains, exhibits superior electronic properties compared to its carbonate‐ester counterpart and outperforms benchmark fulleropyrrolidine with ionic sidechains. These characteristics promote efficient charge‐transport and suppress recombination even under thick‐film conditions. The phosphonate ester groups also endow C60‐BSI‐PS with high solubility in ethanol, eliminating the need for toxic halogenated solvents or methanol. When processed from ethanol, the C60‐BSI‐PS interlayer delivers a power conversion efficiency (PCE) of 19.76% in PM6:D18:L8‐BO‐based OSCs, alongside excellent operational stability. It retains >94% of its optimal PCE even at an ultra‐thick coating of 81 nm. The broad applicability of C60‐BSI‐PS is further demonstrated across leading binary, ternary, and quaternary OSC systems, achieving PCEs 21.11% for small‐area devices (0.04 cm 2 ) and 19.69% for large‐area devices (0.6 cm 2 ) in D18:L8‐BO:BTP‐eC9‐based system. Thus, engineering fullerene‐based materials through judicious sidechain functionalization is a powerful strategy for creating high‐performance, sustainable interlayers, paving the way for next‐generation photovoltaic technologies.