Search Results (1,512)

A physics-informed machine-learning model was created to forecast the dielectric constant of oxide materials. The study explores the physicochemical descriptors that govern the response of the materials. A set of 3304 non-metallic oxide compounds was built using the Materials Project database. A comprehensive feature space with 23 original and composition-derived variables as well as 10 physics-informed engineered variables representing electronic, thermodynamic, structural, magnetic, and chemical descriptors was constructed. This workflow included model benchmarking, hyperparameter optimization, repeated training (10 times) and testing, consensus feature selection, and SHapley Additive exPlanations (SHAP) analysis. Optimized XGBoost model was the model with the best overall predictive ability. A reduced representation of 25 descriptors was obtained by consensus-based feature selection that performed close to the complete 33-descriptor representation (MAE = 0.611, RMSE = 1.052, and R² = 0.699). The SHAP analysis revealed that the descriptors associated with chemical properties, electronic excitation and atomic packing were key to the model predictions. The results indicate that the electronic dielectric response is related to a combination of a few physicochemical aspects instead of a single descriptor. The proposed framework offers an intuitive, data-centric method for examining the evolution of dielectric properties, and it can be used to screen and hypothesize oxide materials with desired electronic dielectric response. Full article

Multilingual students are a rapidly growing population in U.S. schools, yet early literacy research has largely focused on monolingual development and English-only instruction. This mixed-methods quasi-experimental study examined Just Right Reader Take-Everywhere Literacy Packs among Spanish–English bilingual kindergarten and second-grade students in a diverse Texas district during 2024–2025. The sample included 164 kindergarteners (73 treatment, 91 comparison) and 146 second graders (73 treatment, 73 comparison) across two treatment and two comparison schools; sample sizes varied by assessment measure. Treatment students received personalized English and Spanish decodable texts with multilingual family engagement supports, while comparison students used alternative decodable materials. Quantitative outcomes included mClass DIBELS, NWEA MAP Fluency, and NWEA MAP Growth assessments administered from beginning-of-year, middle-of-year, to end-of-year. Qualitative data included parent and educator surveys and interviews. MAP Fluency showed promising patterns in picture vocabulary and listening comprehension across English and Spanish. Second-grade treatment students had significantly higher Spanish MAP Growth RIT scores, t(13) = −2.24, p = 0.043, η²p = 0.235. Qualitative findings indicated increased reading confidence, independence, engagement, and family involvement. Results suggest culturally and linguistically responsive decodable texts with multilingual family supports may strengthen biliteracy development and inclusive literacy opportunities. Full article

External steep-front transient overvoltages may introduce high-frequency electromagnetic disturbances into modular multilevel converter-based high-voltage direct current (MMC-HVDC) systems, resulting in additional transient voltage stresses on converter valves and their sub-modules. This paper investigates the propagation, coupling, and transient voltage distribution characteristics of external high-frequency disturbances in MMC converter valves using a multi-scale wideband equivalent model covering the “sub-module–converter valve–converter station” hierarchy. A wideband equivalent model of a 4.5 kV/3 kA press-pack insulated gate bipolar transistor (IGBT)-based sub-module is developed and integrated with the distributed parasitic parameters of the valve tower and the high-frequency characteristics of converter-station components. To investigate the converter-valve response under different transient conditions, a representative lightning impulse is considered as an engineering transient condition, while a controlled fast-front impulse is employed to investigate the intrinsic high-frequency propagation and resonance characteristics of the distributed converter-valve network. Simulation results demonstrate that external transient disturbances can propagate into MMC converter valves through grounding parasitic capacitances and distributed coupling paths, resulting in additional differential-mode transient voltage stresses at sub-module terminals. Sub-modules closer to the disturbance source experience higher transient voltage peaks and larger dv/dt values. Moreover, multiple local resonance bands are identified within the valve tower, with high-frequency oscillatory components above 10 MHz being strongly influenced by the distributed parasitic network. Parameter analysis further indicates that the sub-module stray inductance has an important influence on the magnitude and oscillatory characteristics of the induced transient voltage. The proposed multi-scale modeling approach provides a practical method for evaluating high-frequency transient voltage stresses in MMC-HVDC converter valves and provides theoretical support for insulation coordination, converter-valve structural optimization, and transient reliability design of HVDC transmission systems. Full article

Long-term groundwater exploitation causes water-level fluctuations, which are a major driver of land subsidence and infrastructure deformation in sedimentary basins. To investigate the stress-history-dependent compression–rebound behavior of deep cohesive soils, soil samples along the Beijing–Tianjin High-Speed Railway were examined using high-pressure consolidation tests, cyclic loading–unloading tests, SEM, and XRD. Prescribed cyclic effective-stress paths were applied to simulate groundwater-level decline and recovery at different burial depths. The results showed that irreversible deformation was highly concentrated in the early loading stage. Under the groundwater-level decline paths, the first loading cycle alone accounted for approximately 77% and 94.8% of the total cumulative compression in the shallow and deep soils, respectively. During repeated loading–unloading between 0 and P₀, the plastic deformation decreased significantly with cycle number, whereas the elastic deformation remained relatively stable. Under the groundwater-level rise paths, the cumulative rebound ratios were only 9.8% for the shallow soils and 17% for the deep soils, indicating that unloading recovered only a small fraction of the preceding compression. In terms of microstructure, the shallow soils had relatively loose and pore-rich fabrics, while the deeper soils exhibited denser particle packing and stronger interparticle contacts. These findings demonstrate pronounced mechanical irreversibility. Together with the measured low permeability, they support a mechanistic interpretation in which slow pore-pressure and effective-stress adjustments may further contribute to delayed deformation. Overall, this study provides a quantitative experimental characterization of the evolution of irreversible compression and incomplete recovery of deep cohesive soils under cyclic effective-stress changes induced by groundwater-level variations. Full article

Hematological parameters and indicators of oxidant–antioxidant balance could provide useful information about the physiological characteristics of poultry. However, information on these parameters in native Turkish white geese of different ages and sexes remains limited. This study evaluated 40 clinically healthy native Turkish white geese aged 16 or 98 weeks (10 females and 10 males per group). Hematology was assessed manually; plasma total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) were measured with commercial kits. Two-way ANOVA was followed by Bonferroni-adjusted comparisons where appropriate. To aid the interpretation of the statistical findings, effect sizes for the main effects of age and sex, as well as for the age × sex interaction, were expressed as partial eta-squared (ηp²) and reported with 95% confidence intervals. The age × sex interaction was significant for erythrocyte count, packed cell volume (PCV), mean corpuscular hemoglobin concentration (MCHC), and all leukocyte parameters except basophil percentage. Young males had higher erythrocyte counts and lower MCHC than adult males, whereas young and adult females had similar values. PCV was higher in young than adult geese within both sexes. Within both sexes, adults had higher total leukocyte counts, heterophil and eosinophil percentages, and heterophil-to-lymphocyte (H/L) ratios, but lower lymphocyte and monocyte percentages. No significant interaction was detected for TAS, TOS, or OSI; TAS was higher in adults, whereas TOS and OSI were higher in females. These results provide comparative data for interpreting hematological and oxidant–antioxidant measurements in native Turkish white geese at two distinct ages under similar rearing conditions. Full article

Greenhouse structural steel pipes are susceptible to internal and external corrosion under hot and humid service conditions, leading to cross-sectional loss and reduced structural strength. This study proposes a cold infrared thermography method for screening corroded pipes and identifies effective indicators for different cooling-affected regions. Experiments were performed using three non-corroded and five salt-spray-corroded SPVHS-grade specimens and three field-corroded specimens. After a cooling stimulus was applied using an ice pack, time-series mean surface-temperature data were acquired using an infrared camera. For the direct cooling region, the recovery phase was fitted with an exponential model to estimate the time constant (τ). For the indirect cooling region, located approximately 50 mm from the direct cooling region, the cooling phase was fitted with a linear model to obtain R² and the root mean square error (RMSE). Mean τ was consistently higher in the non-corroded group than in the combined corroded group across all four environmental conditions. The linearity indices in the indirect cooling region showed only exploratory, condition-dependent group differences. These findings suggest that the recovery time constant may support corrosion screening under controlled conditions. Full article

The uniformity of polymer matrices can strongly influence pattern retention during negative-tone development. In this study, two 3-arm star terpolymers, designated HTM Random and HTM Block, were synthesized via reversible addition–fragmentation chain transfer polymerization using simultaneous and sequential monomer-addition strategies, respectively. Both polymers were prepared using the same nominal feed ratio of 2-hydroxyethyl methacrylate, dicyclopentanyl methacrylate, and 2-methyl-2-adamantyl methacrylate. Although the two materials exhibited controlled molecular weight distributions and similar FT-IR spectral changes after ultraviolet exposure and post-exposure baking, differences were observed in their chain-packing characteristics, thermal behavior, and developed pattern morphology. The two materials exhibited comparable initial thermal stability but distinct multistep degradation profiles and glass-transition behavior. In contrast, the simultaneous-feed material showed more clearly retained and spatially uniform patterns under the tested development conditions. These results indicate that the materials produced by the two monomer-addition strategies exhibited differences in thermal response and development behavior under the investigated conditions. Full article

This study investigates metakaolin-based geopolymer recycled mortar (GRM) in which recycled fine aggregate (RFA) was volumetrically replaced by pumice powder (PP) at 0% and 60–100%. Ambient compressive and tensile bond strengths were measured, followed by exposure to 600–800 °C for 1–3 h. The evaluation encompassed mass loss ratio, residual mechanical properties, temperature sensitivity, micro-phase evolution, and strength-normalized carbon intensity. Results demonstrated that PP replacement produced a non-monotonic response, governed by the trade-off between improved particle packing and the depletion of the rigid granular skeleton. Among the PP-containing mixtures, PP₇₀ (70% replacement) showed a comparatively favorable mechanical response, with an ambient compressive strength of 31.7 MPa and a mean residual compressive strength of 18.8 MPa (59.3% of its initial value) after exposure to 800 °C for 3 h. Notably, tensile bond strength exhibited greater temperature sensitivity than compressive strength, with deterioration accelerating significantly above 700 °C. SEM and XRD analyses elucidated this macroscopic divergence via a two-stage damage mechanism: while dehydration and matrix contraction dominated at 600 °C, prolonged exposure at 800 °C induced structural rearrangement, with the dominant damage becoming increasingly concentrated at the RFA–matrix interface. Although substituting RFA with processed PP inherently increased the absolute embodied carbon, PP₇₀ exhibited the lowest strength-normalized carbon intensity among the modified mixtures after exposure to 800 °C for 3 h. These findings indicate that, among the investigated high-volume PP mixtures, PP₇₀ provided a comparatively favorable compromise between thermal-mechanical performance and environmental cost. Full article

Thermal runaway propagation in large-capacity battery energy storage systems can be driven by casing conduction, vented products, and pack-level thermal coupling. This study experimentally evaluated whether a static dielectric-liquid boundary can prevent propagation between 314 Ah rectangular cells. Three-cell modules were tested in air and in two liquids at relative immersion heights of 10–20 mm, followed by two non-circulating 1P52S pack tests. Propagation was assessed using trigger-cell temperature and venting, adjacent-cell voltage and venting, and post-test state. Under AIR-0, adjacent-cell voltage fell to 0 V and propagation occurred; the trigger cell reached its primary peak of 613 °C at 1560 s, followed by a secondary-heating maximum of 971 °C at 1893 s. All six immersed module tests maintained stable adjacent-cell voltages, with no adjacent-cell venting or propagation, while trigger-cell maximum temperatures were 403–498 °C. Using a common window from trigger-cell venting to its primary peak, the apparent equivalent surface-averaged heat-flux indicator was 31.2 kW/m² in AIR-0 and 22.5–29.3 kW/m² under immersion, corresponding to a reduction of approximately 6.1–27.8%. In both pack tests, no fire, explosion, adjacent-cell venting, or pack-level propagation occurred. Under the tested module and pack configurations, no propagation from the trigger cell to adjacent cells was observed with static immersion, supporting its potential as a passive safety boundary for large-capacity battery storage systems. Full article

Raw mix-design variables used to predict ultra-high-performance concrete (UHPC) properties cannot fully represent internal proportions and structural compatibility. This study develops mechanism-informed proxy-core features based on particle packing, water film thickness, and rheology, and evaluates four feature systems using literature-derived datasets for compressive strength (924 samples), flexural strength (406 samples), and slump flow (192 samples). Eight regression models were compared using five-fold cross-validation, Bayesian optimization, SHAP, and ablation analysis. Proxy-W achieved an R² of 0.918 for compressive strength, only 0.005 higher than baseline-W on the original split. For flexural strength, baseline-WB achieved the highest R² (0.906), whereas proxy-W yielded the lowest MAE (2.140 MPa). The largest single-split difference occurred for slump flow (R²: 0.740 to 0.838 for W-based systems), but 30 repeated splits yielded mean R² values of 0.667 ± 0.169 and 0.738 ± 0.101 for baseline-W and proxy-W, respectively, while proxy-WB showed no average improvement over baseline-WB. Repeated and source-group validation further indicated that the predictive effects of proxy-core features were property-, representation-, partition-, and source-dependent. Overall, proxy-core features are best interpreted as physically informed relational representations rather than universally accuracy-enhancing features. Full article

This study presents the FlowPCM concept, a mobile thermal energy storage (M-TES) system based on encapsulated phase change material (PCM) for waste heat recovery and potential integration with district heating and local heat supply systems. Unlike conventional M-TES solutions with stationary PCM beds, FlowPCM uses capsules containing ferromagnetic elements, enabling their magnetic handling and potential direct-contact charging in selected waste heat streams. The study combines a state-of-the-art comparison, capsule design and packing assessment, preliminary thermal calculations, and laboratory magnetic interaction tests. For the analysed industrial waste streams at 70–90 °C, the available thermal potential substantially exceeded the nominal storage capacity of a single FlowPCM unit (7.2 GJ), indicating that heat availability would not be the limiting factor in the considered application. Preliminary magnetic tests confirmed capsule attraction and lifting using permanent magnets. Depending on the magnet configuration, the first observable capsule interaction occurred at approximately 85–110 mm, while effective attraction suitable for practical handling occurred below approximately 50–60 mm. These results provide preliminary support for the technical feasibility of magnetically assisted capsule handling; however, direct-contact charging, long-term capsule durability, thermal performance, and magnetic recovery under representative industrial conditions still require experimental validation. Full article

This paper investigated the lubricant stability and anti-biofouling performance on slippery liquid-infused nanostructured surfaces (SLIPSs) using thermodynamic and interfacial energy analyses. ZnO nanorods were synthesized on indium tin oxide substrates with and without a ZnO seed layer by electrochemical deposition and subsequently infused with PDMS-based silicone oil. The seed-layer-assisted growth produced densely packed and vertically aligned ZnO nanorods. Interfacial energy analysis showed that the resulting SLIPSs satisfied the criterion for resistance to water-induced lubricant displacement (ΔE₂ = 64.14 mJ·m⁻²), indicating effective lubricant retention, whereas non-seeded surfaces exhibited reduced lubricant stability. Consistent with this prediction, the seed-layer-assisted SLIPSs retained droplet mobility following spin testing at 2500 rpm, although the reduced sliding velocity indicated a decline in slippery performance. Anti-biofouling evaluation using Escherichia coli (XL1-Blue) revealed that the SLIPSs effectively suppressed bacterial attachment, reducing surface coverage to below 0.3% after 24 h of incubation. In comparison, the pristine ITO and ZnO nanorods exhibited values of 50.8% and 54.6%, respectively. Subsequent surface free energy analysis demonstrated that lubricant infusion reduced the work of adhesion to 77.92 mJ·m⁻². These findings provide insight into the interfacial interactions governing lubricant retention and bacterial attachment on SLIPSs. Full article

A new nitro- and cyano-functionalized, tetradecyl-substituted benzothienoquinolizinium tetrafluoroborate was synthesized through oxidative photocyclisation of a pyridinium precursor and evaluated as a potential small molecule N-type organic semiconductor. The precursor and the photocyclised salts were characterized by UV–Vis absorption spectroscopy, DSC, ¹H and ¹³C NMR, and cyclic voltammetry. Their optoelectronic properties were further investigated by DFT and TD-DFT calculations. Photocyclisation induced a marked bathochromic extension of the absorption profile, decreasing the optical band gap from 3.19 eV for the pyridinium precursor to 2.61 eV for the fused benzothienoquinolizinium salt. Cyclic voltammetry revealed a stabilized electrochemical LUMO level of approximately −3.87 eV, supporting the electron-deficient character of the nitro/cyano-substituted cationic scaffold. Frontier molecular orbital analysis showed that the HOMO and LUMO are mainly localized on the fused π-conjugated core and electron-withdrawing aryl substituents, with negligible contribution from the tetradecyl chain and BF₄⁻ counterion. TD-DFT and electron excitation analyses indicated that the monomeric low-energy transition has mixed local/charge-transfer character, whereas π-stacked dimers, especially the face-to-face arrangement, enhance charge transfer character and reduce electron–hole Coulombic attraction. Marcus type charge transport calculations revealed packing dependent behavior, with the face-to-face dimer displaying nearly ambipolar transport with a slight electron preference. A preliminary theoretical donor–acceptor model with hexaphenyl-substituted hexabenzocoronene further suggested energetic compatibility and strong intermolecular charge-transfer character. Overall, these results identify this benzothienoquinolizinium tetrafluoroborate as a promising electron-deficient cationic π-scaffold for future organic optoelectronic materials. Full article

Leucine zippers are parallel coiled-coil dimers composed of two α-helices with a repeating heptad pattern, designated as a–g. Hydrophobic residues at the a and d positions form the dimerization core, whereas charged residues at the e and g positions generate interhelical electrostatic interactions that influence stability and specificity. Oppositely charged e–g pairs are generally considered stabilizing, whereas like-charged pairs are expected to be destabilizing. However, their collective effects across an extended leucine zipper interface have not been systematically evaluated. Here, we designed a 40-residue homodimeric leucine zipper containing 10 e–g interaction positions. Ten e–g positions were independently assigned to one of three states—neutral, salt-bridge-forming, or repulsive—yielding 59,049 models. Each model was then analyzed with FoldX to calculate the interaction energy and component energy terms. Increasing the number of salt bridges progressively improved the interaction energy, with an average stabilization of 1.68 kcal/mol relative to neutral pairs. Unexpectedly, repulsive pairs were also modestly favorable relative to neutral pairs, improving interaction energy by 0.48 kcal/mol. Energy decomposition showed that favorable solvation and van der Waals contributions outweighed the electrostatic penalty. These effects were position-dependent, indicating that leucine zipper stability reflects a balance of electrostatics, solvation, packing, and positional context. Full article

Natural carrier systems that integrate structural integrity with protective function are critical for the efficient delivery of lipophilic bioactives. Here, we employed Ampelopsis grossedentata leaf powder (AGP), a flavonoid-rich plant material, as a particulate stabilizer to construct Pickering emulsion gels. The influence of AGP concentration and oil phase volume fraction on gel structure was examined, and the ability of the gels to protect lutein was further assessed. AGP displayed appropriate interfacial wettability, enabling it to adsorb at the oil–water interface and build a coherent particle layer. A progressive increase in AGP concentration reduced droplet size and raised gel strength from 3.07 × 10⁻² N to 5.04 × 10⁻² N, reflecting the formation of a more robust particle-based network. Among the formulations tested, the gel prepared with 4% AGP gave the best overall structural performance: it had the highest gel strength, together with favorable elasticity index (EI) and macroscopic viscosity index (MVI) values, indicative of superior load-bearing capacity and disturbance resistance. Raising the oil phase fraction further tightened droplet packing and improved structural stability. In storage trials, the optimized AGP-stabilized emulsion gel retained substantially more lutein than the MCT oil system without powder, with the 7-day retention increasing from 14.9% to 55.9%. This protective effect may be attributed to the physical barrier created by interfacial particles, together with the antioxidant activity of flavonoids naturally present in AGP. These findings uncover a synergistic role of plant-based particles in structuring Pickering emulsion gels and preserving lipophilic bioactives, highlighting AGP as a sustainable and functional platform for delivery systems. Full article