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Crosslinking of Linear Polyimines Into Aminal‐Linked Porous Organic Polymers for C <sub>2</sub> Hydrocarbon/Methane Separation
ABSTRACT Hypercrosslinked polymers, a class of porous organic polymers (POPs), are constructed by crosslinking linear polymers or knitting small aromatic molecules with a molecular crosslinker, typically via Friedel–Crafts alkylation. In this study, we report a new approach for the synthesis of POPs via the crosslinking of linear polyimines with m ‑phenylenediamine through nucleophilic addition of amines to imines, forming aminal linkages. The resulting aminal‐linked POPs, with an estimated low cost of 16 USD/kg, exhibited high surface areas up to 650 m 2 /g and abundant microporosity, in contrast to the ∼100 m 2 /g observed for the linear polyimine. This method demonstrated good generality: four linear polyimines with different structures were successfully crosslinked into POPs with high porosity. Both experimental results and theoretical calculations indicate that the use of diamines at the meta‐position is critical for efficient crosslinking, whereas para‐diamines did not initiate crosslinking. With their high surface area and rich microporosity, these POPs displayed high adsorption capacities for C 2 hydrocarbons and CO 2 , but significantly lower capacity for CH 4 . Dynamic breakthrough experiments confirmed excellent separation performance for C 2 hydrocarbons/CH 4 mixtures, highlighting their potential for hydrocarbon separation. This study provides a new strategy for the synthesis of cost‐effective POPs and demonstrates their promising applications in gas separation.
A data-driven method to assess indoor climate response to outdoor conditions in heavy-weight buildings for adaptive reuse
Surface BO <sub>3</sub> Configuration in Li‐Rich Cathode Materials Enabling Highly‐Stable Anionic Redox Reactions
ABSTRACT Li‐rich Mn‐based layered oxides (LRMOs) are considered promising cathode candidates for next‐generation high‐energy‐density lithium batteries, owing to their high capacity and low cost. However, they are plagued by lattice‐oxygen release and surface‐driven structural degradation, which lead to low initial coulombic efficiency and poor cycling stability. Here, a B‐heterogeneous coordination structure is incorporated into the Li‐rich materials, forming a ≈4 nm surface layer enriched in BO 3 units while retaining BO 4 units within the bulk. Both of tetrahedral BO 4 and trigonal BO 3 display stronger bonding interaction than those of transition metal (TM)─O bonds (i.e., Mn─O, Ni─O, and Co─O), while surface BO 3 further strengthens the B─O bonds compared with bulk BO 4 , thus robustly anchoring lattice oxygen to suppress irreversible oxygen loss. Benefiting from this synergistic heterogeneous coordination, the modified LRMOs deliver a high reversible capacity of ∼300 mAh g −1 at 0.1C, an enhanced initial Coulombic efficiency of 93.5% and excellent capacity retention of 85.8% after 300 cycles at 1C. This work demonstrates the surface BO 3 structure as an effective paradigm to reconcile oxygen‐redox activity with long‐term stability in high‐energy‐density lithium batteries.
Smart urban utility management using ML-based prediction of pipeline performance in the sustainable water supply network of Jamshedpur industrial city
Interstitial Copper Doping and Thermally Activated Rattling in La <sub>3‐</sub> <i> <sub>x</sub> </i> Te <sub>4</sub> for Enhanced Thermoelectric Performance
ABSTRACT La 3‐ x Te 4 materials are ideal candidates for next‐generation radioisotope thermoelectric generators due to their excellent thermoelectric performance and high‐temperature stability. For decades, researchers have used substitutional doping or vacancy modulation to tune carrier concentration, but these methods can only tune it without optimizing the conduction band structure or suppressing lattice thermal conductivity. Interstitial doping strategy breaks this deadlock by enabling simultaneous electronic and thermal regulation without mutual interference. Herein, a series of Cu‐doped La 2.74 Cu x Te 4 ( x = 0, 0.01, 0.05, 0.1, 0.15) samples were synthesized. Cu incorporation elevates the Seebeck coefficient without degrading significantly the power factor, while simultaneously suppressing lattice thermal conductivity via anharmonic vibrational behavior that strengthens low‐frequency acoustic phonon modes and intensifies phonon‐phonon scattering. Among the synthesized compositions, La 2.74 Cu 0.05 Te 4 achieves a peak thermoelectric figure of merit of 1.58 at 1073 K, representing a 34% improvement over the undoped La 2.74 Te 4 . Furthermore, the material exhibits a notable average zT value of 1.5 within the operational temperature range of 873–1073 K. When compared to the previously reported state‐of‐the‐art lanthanum telluride‐based thermoelectrics, this represents a significant improvement of 71.3% in the average zT value.
Individually timed upper-limb post-activation performance enhancement improves 50 m front crawl performance in national-level swimmers
Abstract Post-activation performance enhancement (PAPE) has been proposed as an acute strategy to improve sprint performance, yet evidence in swimming remains inconsistent, particularly for upper-limb protocols and segment-specific race outcomes. This study examined the acute effects of an individually timed upper-limb PAPE procedure on 50 m front crawl performance and selected race-kinematic variables in national-level male swimmers. Fifteen swimmers completed a randomized repeated-measures cross-over design comprising a control condition (CON) and an upper-limb PAPE condition. The PAPE procedure consisted of 3 sets of 6 repetitions of a prone butterfly-style double-arm pull exercise at 70% 1RM on a Keiser Functional Trainer, followed by a maximal 50 m front crawl trial performed after each swimmer’s individually determined recovery time. The primary outcome was 50 m race time (T50), while start-, split-, turn-, and lap-specific stroke variables were analyzed as secondary exploratory outcomes. Compared with CON, the PAPE condition resulted in significantly faster T50 (25.44 ± 0.80 vs. 25.70 ± 0.78 s; Δ = −0.260 s, − 1.01%; p < 0.001) and T50 excluding reaction time ( p < 0.001). Significant improvements were also observed for T15, T20, dive distance, flight time, turn time, and second-length stroke rate, whereas lap-specific swimming velocity, stroke length, and stroke index remained unchanged. These findings suggest that an individually timed upper-limb PAPE procedure may improve 50 m front crawl performance in national-level male swimmers, with effects expressed mainly through selected race segments rather than a uniform enhancement of free-swimming efficiency.
Synergistic Anion‐Reinforced Solvation Chemistry and Cationic Electrostatic Shielding for Fast‐Charging Sodium‐Ion Full Batteries Over a Wide Temperature Range
ABSTRACT Sodium‐ion batteries (SIBs) capable of stable operation under fast‐charging conditions across a wide temperature range are of great significance for the efficient utilization of intermittent renewable clean energy. Herein, a multifunctional electrolyte additive containing tetrabutylammonium (TBA + ) cation and perchlorate (ClO 4 − ) anion is employed to construct an environmentally friendly fluorine‐free electrolyte system, significantly enhancing the temperature tolerance and fast‐charging performance of SIBs. Specifically, the TBA + cations, due to their low reduction potential, induce an electrostatic shielding effect that guides the uniform distribution of Na + flux on the electrode surface. Meanwhile, the introduced ClO 4 − anions facilitate the formation of the anion‐reinforced solvation structure. This structure effectively reduces the desolvation energy barrier of Na + and promotes the formation of a stable electrode‐electrolyte interface with high ionic conductivity. This synergistic mechanism effectively suppresses Na plating during fast charging and mitigates continuous electrolyte decomposition and transition metal dissolution. Consequently, the assembled Prussian blue||hard carbon (PB||HC) full cell demonstrates excellent fast‐charging performance across a wide temperature range (10–100°C). More importantly, the PB||HC 18650 cylindrical cell exhibits a superior cycling stability and outstanding rate performance at an elevated temperature of 55°C, demonstrating the great potential of this electrolyte system for practical applications.
HCCD-DS v2: a transparent synthetic benchmark for human–AI decision support under contextual uncertainty
Abstract Decision support pipelines increasingly combine machine learning predictions with human judgment, yet most public benchmarks evaluate model outputs only and do not encode the interaction process that determines final decisions. This limits reproducible analysis of when human intervention improves or degrades system-level performance. We introduce HCCD-DS v2, a transparent and configurable synthetic benchmark dataset that models decision-time interaction between an AI recommender and simulated users with continuous expertise levels under contextual uncertainty. Each decision instance links input context, system confidence, explainability metadata, human acceptance/override behavior, override rationale, and realized outcome. The dataset simulates distinct profiles for healthcare, cybersecurity, and Internet of Things (IoT) scenarios to support cross-domain evaluation. Empirical analyses and benchmark experiments show that human intervention is condition-dependent: expert overrides are more likely to improve outcomes, while novice overrides more often reduce success. By exposing this interaction in a unified and reusable resource under explicit behavioral assumptions (sequential trust updates, individual risk tolerance, and explanation sensitivity), HCCD-DS v2 provides a controlled environment for benchmarking trust calibration, explanation-aware interaction policies, and algorithms that learn to defer. We discuss the limits of predictive recoverability in simulated human behavior and frame the benchmark’s F1-score transitions as a measure of policy complexity.
Flame‐Retardant Quasi‐Solid‐State Electrolytes From Self‐Assembled Azolate Hybrid Frameworks for Highly Safe Lithium Batteries
ABSTRACT Achieving quasi‐solid‐state electrolytes (QSSEs) that simultaneously deliver fast ion transport and intrinsic thermal safety remains a central challenge for lithium batteries, as improvements in ionic conductivity are often coupled with increased flammability and interfacial instability. Here, we present a spray‐assisted in situ assembly strategy to construct azolate hybrid frameworks (AHFs) directly on glass fiber substrates, followed by thermal polymerization to yield a chemically integrated QSSE. The heterocyclic AHF provides ordered lithium‐philic coordination sites and continuous ion‐transport pathways, enabling efficient Li + migration while maintaining high thermal robustness. As a result, the resulting LiFePO 4 |FP10v‐GF|Li cell sustains stable cycling for over 500 cycles at 25°C and 100 cycles at 60°C. Notably, the framework architecture enables molecular level confinement of triethyl phosphate (TEP) as a flame‐retardant component, establishing a nitrogen phosphorus synergistic flame‐retardant mechanism without compromising electrochemical compatibility. Consequently, high‐loading Li||LiFePO 4 cells exhibit stable cycling under practical conditions (E/C = 0.56 g Ah −1 , N/p = 3.27) and successfully withstand accelerated rate calorimetry tests from 25°C to 300°C without thermal runaway. This work demonstrates how framework chemistry and molecular confinement can be synergistically integrated to decouple ionic conductivity from flammability, providing a general design principle for intrinsically safe, high‐energy quasi‐solid‐state lithium batteries.
Parametric analysis of miniature pulse tube cryocooler regenerators at very high frequencies using REGEN 3.3
Water‐Mediated SEI in Fluorinated Alkoxylborate Electrolytes for Long‐Cycling Calcium Metal Anodes
ABSTRACT The practical implementation of calcium metal anodes in rechargeable batteries is persistently hindered by surface passivation, which impedes Ca 2+ transport and induces inhomogeneous Ca deposition. Herein, we demonstrate that introducing a tailored trace amount of water (∼139 ppm) fundamentally modifies the interfacial chemistry in a state‐of‐the‐art Ca[B(hfip) 4 ] 2 /DME electrolyte. Mechanistic investigations reveal that instead of triggering deleterious bulk side reactions, the trace water stably enters Ca 2+ solvation sheath, directing a controlled electrochemical hydrolysis pathway during cycling. This process generates a thin, uniform bilayer solid electrolyte interphase (SEI) comprising an outer hybrid organic‐inorganic layer and an inner inorganic layer rich in CaH 2 , CaO, and CaF 2 , while concurrent H 2 evolution effectively eliminates the passivating native oxide layer. Consequently, this tailored SEI enables highly stable Ca plating/stripping for over 400 h at 0.2 mA cm −2 and over 300 h at 1 mA cm −2 . Furthermore, the high anodic stability of the electrolyte enables reliable operation of various high‐voltage cathodes within a wide voltage window (up to 4.5 V) for up to 70 cycles. These results highlight the critical role of a stable SEI for Ca metal anodes, but also illustrate how subtle electrolyte modification can profoundly regulate the interfacial chemistry toward high‐performance multivalent batteries.
Zero-voltage transition soft-switching step-up Cuk power factor converter circuit
Tuning the Mechanical Properties of Crosslinked Copolymers via Sequence and Solvent‐Selective Swelling for Vat Photopolymerization
ABSTRACT Block copolymers (BCPs) offer distinct advantages for vat photopolymerization by enabling mechanically programmable network structures through microphase‐separated morphologies that can be kinetically trapped during curing, yielding properties unattainable in homogeneous resins. However, the respective roles of repeat‐unit sequence and solvent environment, together with their interplay in directing network formation and mechanical performance, remain unclear. Here, we synthesize a series of CO 2 ‐based polycarbonate copolymers comprising a crosslinkable glassy poly(vinyl cyclohexene carbonate) (PVCHC, A block) and a non‐crosslinkable soft poly(propylene carbonate) (PPC, B block). The polymer sequence is systematically varied (ABA, BAB, and statistical), and solvent choice controls block‐selective swelling to jointly control gelation behavior, microphase morphology, and mechanical response through changes in the accessibility and local environment of photocrosslinkable vinyl groups during network formation, as revealed by photorheology and small angle x‐ray scattering. By tuning polymer sequence and curing solvent, we transform nominally identical formulations from brittle to highly ductile materials, achieving a three‐orders‐of‐magnitude range in toughness (0.003 to 9.1 MJ m −3 ). These results establish clear structure–processing–property relationships and identify polymer sequence and selective solvation as powerful strategies for programming both printability and performance of block copolymer resins for additive manufacturing.
No effect of acute pain or self-reported chronic pain on working memory in the Sternberg task
Psychological resilience mediates associations between stress related factors and short video addiction among university students
Electrochemically Triggered Supramolecular Polymerization Under Kinetic Control
ABSTRACT Stimuli‐responsive supramolecular polymerization with high precision is essential for developing adaptive materials with programmable kinetics and functions. Here, we present a redox‐responsive strategy that integrates chemical redox reactions and electrochemical potential to direct the self‐assembly of a perylene diimide–histidine ( PDI – His ). A chemical redox process with sodium dithionite (SDT) rapidly converts kinetically trapped dimeric aggregates (Agg‐I) of PDI – His stabilized by intramolecular hydrogen bonding into thermodynamically favored helical nanofibers (Agg‐II), enabling the preparation of seeds with tunable lengths. Electrochemical potential application also induces reorganization of Agg‐I into Agg‐II, accompanied by morphological evolution, and improved conductivity via enhanced π–π stacking. Importantly, the redox‐cycle‐driven supramolecular reorganization was achieved not only on electrode surfaces through electrochemical stimuli but also through seeded‐living supramolecular polymerization using seeds generated via both chemical and electrochemical kinetic pathways, yielding nanofibers with predictable lengths. This combined chemical‐ and electrochemical‐redox approach provides an adaptable platform for controlling pathways in supramolecular polymerization, advancing the design of stimuli‐responsive materials for applications in electronics, sensing, catalysis, and bioinspired systems.
Direct and indirect regulation of fetal globin transcript by RNA-binding protein IGF2BP1
Despite extensive investigation, the molecular control of developmental hemoglobin expression remains incompletely elucidated. Hemoglobin switching is controlled by transcription factors, miRNAs, and RNA-binding proteins (RBPs) that enforce gene regulatory changes through development. Here we examine the role of the heterochronically silenced N6 methyladenosine (m6A) RNA-binding protein IGF2BP1 that was previously described to regulate HBG1/2 indirectly by suppressing BCL11A expression through an unknown mechanism. We find that IGF2BP1 binds and activates HIC2, itself a BCL11A repressor. Furthermore, we identify that IGF2BP1 plays a BCL11A-independent role by direct binding to HBG1/2 to promote its translation. Stop codon-proximal m6A-modified coding sequences within HBG2 transcripts are necessary and sufficient for direct positive regulation mediated by IGF2BP1. This work deepens the mechanistic understanding of hemoglobin switching and suggests a physical relationship between heterochronic RBPs and globin transcripts.