Search Results (7,088)

High electrostrain, excellent thermal stability, and low hysteresis are critical requirements for advanced high-precision actuators. However, simultaneously achieving these synergistic properties in lead-free ferroelectric ceramics remains a significant challenge. In this work, a targeted B-site doping strategy was employed to develop novel lead-free (0.99-x)BaTiO₃-xBaZrO₃-0.01Bi(Zn_2/3Nb_1/3)O₃ (BT-xBZ-BZN, x = 0–0.2) ceramics. Systematic investigation identified optimal Zr⁴⁺ substitution at x = 0.1, which yielded an outstanding combination of electromechanical properties. For this optimal composition, a high unipolar electrostrain (S_max = 0.11%) was achieved at 50 kV/cm, accompanied by an ultra-low hysteresis (H_S = 1.9%). Concurrently, a large electrostrictive coefficient (Q₃₃ = 0.0405 m⁴/C²) was determined, demonstrating excellent thermal robustness with less than 10% variation across a broad temperature range of 30–120 °C. This superior comprehensive performance is attributed to a composition-driven evolution from a long-range ferroelectric to a pseudocubic relaxor state. In this state, the dominant electrostrictive effect, propelled by reversible dynamics of polar nanoregions (PNRs), minimizes irreversible domain switching. These findings not only present BT-xBZ-BZN (x = 0.1) as a highly promising lead-free candidate for high-precision, low-loss actuator devices, but also provide a viable design strategy for developing high-performance electrostrictive materials with synergistic large strain and superior thermal stability. Full article

The increasing challenges of urbanization and environmental degradation have led to a greater need for built environments that minimize ecological consequences while actively contributing to ecosystem services (ES). Bio-Inspired Design (BID) is a promising approach that translates natural-system ideas into architectural and urban solutions. This study investigates how BID can be used to deliver and improve ecosystem services, like climate regulation, air purification, and energy, in the built environment, focusing on applications in hot climates and at the meso scale. The study conducts a qualitative and integrative analysis of bio-inspired concepts derived from existing research and innovative practices. It examines specific ecosystem services—selected based on previous studies—and illustrates how these strategies can improve environmental performance in urban contexts. A conceptual framework for linking biological analogies to urban functions is proposed. The framework emphasizes the interdisciplinary relationships between architecture, urban design, material science, and environmental engineering. This provides a helpful guide for researchers and practitioners on how to use BID to enhance sustainability results. The study suggests that incorporating BID principles into urban design procedures can potentially transform built environments into active contributors to ecosystem functioning, enabling them to provide ES rather than merely consuming resources. While this conclusion is conceptual, the framework highlights pathways for more resilient and sustainable urban futures. Full article

How would it be possible to functionalize ceramic aggregates for use in refractories? In this work, we demonstrate how paste extrusion can be used to fabricate layered and porous Nb-Al₂O₃-based composite refractories for adjusting thermal and electrical conductivity. Additive manufacturing is used to generate a specific sequence of alumina and composite layers. After drying, the samples were sintered at 1600 °C, crushed, and sieved into particle sizes up to 3150 µm. The rheology of the paste revealed the intended shear-thinning behavior with microcrack formation between the yield and flow strain. The sintered material showed promising thermal-shock characteristics reaching plateau values after the third cycle without signs of further structural damage up to the fifth thermal shock. The layered microstructure was retained after crushing the composites, establishing functionalization of the refractory granules for all particle sizes. Full article

The impacts of land use on stormwater runoff quality and Best Management Practices to mitigate these impacts have been investigated since the 1970s, yet challenges remain in providing a modeling approach that concomitantly considers contributions from different land use types. In densely developed urban areas, a buildup/washoff approach is often applied, while in rural areas, some type of erosion modeling is employed, as the processes of detachment, entrainment, and transport are fundamentally different. This study presents a coupled modeling approach within PCSWMM, integrating exponential buildup/washoff for impervious surfaces with the Modified Universal Soil Loss Equation (MUSLE) for pervious areas, including construction sites, to characterize water quality in the large mixed urban–rural Sparrovale catchment in Geelong, Australia. The watershed includes an innovative cascading system of 12 online NbS wetlands along one of the main tributaries, Armstrong Creek, to manage runoff quantity and quality, as well as 16 offline NbS wetlands that are tributary to the online system. A total of 78 samples for Total Suspended Solids (TSS), Total Phosphorus (TP), and Total Nitrogen (TN) were collected from six monitoring sites along Armstrong Creek during wet- and dry-weather events between May and July 2024 for model validation. The data were supplemented with six other catchment stormwater quality datasets collected during earlier studies, which provided an understanding of water quality status for the broader Geelong region. Results showed that average nutrient concentrations across all the sites ranged from 0.44 to 2.66 mg/L for TP and 0.69 to 5.7 mg/L for TN, spanning from within to above the ecological threshold ranges for eutrophication risk (TP: 0.042 to 1 mg/L, TN: 0.3 to 1.5 mg/L). In the study catchment, upstream wetlands reduced pollutant levels; however, downstream wetlands that received runoff from agriculture, residential areas, and, importantly, construction sites, showed a substantial increase in sediment and nutrient concentration. Water quality modeling revealed washoff parameters primarily influenced concentrations from established urban neighborhoods, whereas erosion parameters substantially impacted total pollutant loads for the larger system, demonstrating the importance of integrated modeling for capturing pollutant dynamics in heterogeneous, urbanizing catchments. The study results emphasize the need for spatially targeted management strategies to improve stormwater runoff quality and also show the potential for cascading wetlands to be an important element of the Nature-based Solution (NbS) runoff management system. Full article

This study presents an improved Nishenko–Buland (NB) model to address systematic biases in estimating the coefficient of variation for earthquake recurrence intervals based on a normalizing function ${\displaystyle \frac{\mathrm{T}}{{\mathrm{T}}_{\mathrm{a}\mathrm{v}\mathrm{e}}}}$. Through Monte Carlo simulations, we demonstrate that traditional NB methods significantly underestimate the coefficient of variation when applied to limited paleoseismic datasets, with deviations reaching between 30 and 40% for small sample sizes. We developed a linear transformation and iterative optimization approach that corrects these statistical biases by standardizing recurrence interval data from different sample sizes to conform to a common standardized distribution. Application to 26 fault segments across 15 major active faults in the Hetao graben system yields a corrected coefficient of variation of α = 0.381, representing a 24% increase over the traditional method (α₀ = 0.307). This correction demonstrates that conventional approaches systematically underestimate earthquake recurrence variability, potentially compromising seismic hazard assessments. The improved model successfully eliminates sampling bias through iterative convergence, providing more reliable parameters for probability distributions in renewal-based earthquake forecasting. Full article

This study aimed to experimentally investigate the differences in metallic structures owing to the gas nitriding and quenching process (GNQP) temperature of the Ti-15mass%Nb alloy and differences in the tribological properties of the surface layer. The GNQP heating temperature was 1023 K or 1223 K, and the holding time was set to 1 h. In the X-ray diffraction profiles, the diffraction peak of the (10$\overline{1}$1) plane of the hexagonal close-packed phase exhibited a shift toward lower angles, following the sequence AN:α, AQ:α′, and GNQP:α-TiN_0.3. In both the 1023 K and 1223 K GNQP specimens, the α″ phase exhibited lower values than the α′ phase; nonetheless, it still exhibited larger values than the annealed α phase. Based on transmission electron microscopy observations, the high core hardness of the 1223 K GNQP specimen was attributed to solid-solution strengthening caused by nitrogen diffusion or to strain hardening associated with the diffusion and was not attributed to the influence of precipitation phases, such as the ω phase. In the friction and wear tests, both the 1023 K and 1223 K GNQP specimens exhibited narrower wear track widths, clearly demonstrating that the GNQP enhanced the wear resistance. Moreover, the TiO₂ layer was effective in maintaining a low coefficient of friction. Full article

Among corrosive environments, Cl⁻ is one of the most aggressive anions which can cause electrochemical corrosion and the resultant failures of alloys, and the increase in Cl⁻ concentration will further deteriorate the passive film in many conventional alloys. Here, we report single-phase Nb₂₅Mo₂₅Ta₂₅Ti₂₀W₅C_x (x = 0.1, 0.3, 0.8 at.%) refractory high-entropy alloys (RHEAs) with excellent corrosion resistance in high-concentration NaCl solutions. According to potentiodynamic polarization, electrochemical impedance spectroscopy, corroded morphology and the current–time results, the RHEAs demonstrate even better corrosion resistance with the increase in NaCl concentration to 23.5 wt.%, significantly superior to 304 L stainless steel. Typically, the corrosion current density (i_corr) and over-passivation potential (E_t) reached the lowest and highest value, respectively, in the 23.5 wt.% NaCl solution, and the i_corr (2.36 × 10⁻⁷ A/cm²) of Nb₂₅Mo₂₅Ta₂₅Ti₂₀W₅C_0.1 alloy is nearly two orders lower than that of 304 L stainless steel (1.75 × 10⁻⁵ A/cm²). The excellent corrosion resistance results from the formation of passive films with fewer defects and more stable oxides. Moreover, with the addition of the appropriate C element, the RHEAs also demonstrated improved strength and plasticity simultaneously, for example, the Nb₂₅Mo₂₅Ta₂₅Ti₂₀W₅C_0.3 alloy exhibited an average yield strength of 1368 MPa and a plastic strain of 19.7%. The present findings provide useful guidance to address the conflict between the excellent corrosion resistance and high strength of advanced alloys. Full article

The increasing need for sustainable wastewater treatment technologies has accelerated the development of Nature-Based Solutions (NBS), including hydroponic systems applied as tertiary treatment. This study aimed to assess changes in algal species composition in hydroponically treated municipal wastewater and to evaluate whether laser granulometry can be used as a rapid tool for preliminary identification of algal taxa. The experiment was conducted in a static hydroponic system with three macrophyte species (Pistia stratiotes, Limnobium laevigatum, and Myriophyllum verticillatum) under white and red–blue light conditions. Microscopic identification was compared with indirect indicators such as chlorophyll a concentration and particle size distribution (D-values) obtained using laser granulometry. The results showed a substantial reduction in cyanobacteria and a shift towards diatoms and green algae, demonstrating the ecological benefits of hydroponic NBS. However, regression analysis revealed no significant correlation between algal cell volume and D(3.0) or D(4.3) values (R² < 0.06, p > 0.38), excluding the use of granulometric data for taxonomic purposes. This limitation complicates monitoring of potentially harmful cyanobacteria in effluent and may necessitate additional algal removal before discharge Full article

The classification of breast cancer using machine learning techniques has become a critical tool in modern medical diagnostics. This study analyzes the performance of hybrid models that combine traditional machine learning algorithms (TMLAs) with a convolutional neural network (CNN)-based VGG16 model for feature extraction to improve accuracy for classifying eight breast cancer subtypes (BCS). The methodology consists of three steps. First, image preprocessing is performed on the BreakHis dataset at 400× magnification, which contains 1820 histopathological images classified into eight BCS. Second, the CNN VGG16 is modified to function as a feature extractor that converts images into representative vectors. These vectors constitute the training set for TMLAs, such as Random Forest (RF), Support Vector Machine (SVM), K-Nearest Neighbors (KNN), and Naive Bayes (NB), leveraging VGG16’s ability to capture relevant features. Third, k-fold cross-validation is applied to evaluate the model’s performance by averaging the metrics obtained across all folds. The results reveal that hybrid models leveraging a CNN-based VGG16 model for feature extraction, followed by TMLAs, achieve accuracy outstanding experimental accuracy. The KNN-based hybrid model stood out with a precision of 0.97, accuracy of 0.96, sensitivity of 0.96, specificity of 0.99, F1-score of 0.96, and ROC-AUC of 0.97. These findings suggest that, with an appropriate methodology, hybrid models based on TMLA have strong potential in classification tasks, offering a balance between performance and predictive capability. Full article

A knowledge of the process–structure–property correlation and underlying deformation mechanisms of material under a coupled electro-thermal–mechanical field is crucial for developing novel electrically assisted forming techniques. In this work, numerical simulation and experimental analyses were carried out to study the non-uniform deformation behaviors and microstructure evolution of Ti₂AlNb-based alloy stiffened panels in different characteristic deformation regions during electrically assisted press bending (EAPB). The quantitative relationships between electro-thermal–mechanical routes, microstructural features, and mechanical properties of EAPBed stiffened panels were initially established, and the underlying mechanisms of electrically induced phase transformation and morphological transformation were unveiled. Results show that the temperature of the panel first increases then deceases with forming time in most regions, but it increases monotonically and reaches its peak value of 720.1 °C in the web region close to the central transverse rib. The higher accumulated strain and precipitation of the acicular O phase at mild temperature leads to strengthening of the longitudinal ribs at near blank holder regions, resulting in an ideal microstructure of 3~4% blocky α₂ phase + a dual-scale O structure in a B2 matrix with a maximal hardness of 389.4 ± 7.2 HV_0.3. While the dissolution of the α₂ phase and the spheroidization and coarsening of the O phase bring about softening (up to 9.29%) of the lateral ribs and web near the center region, the differentiated evolution of microstructure and the mechanical property in EAPB results in better deformation coordination and resistance to wrinkling and thickness variation in the rib–web structure. The present work will provide valuable references for achieving shape-performance coordinated manufacturing of Ti₂AlNb-based stiffened panels. Full article

Cumulus cells (CCs) are a distinct population of granulosa cells (GCs) that surround the developing and ovulated mammalian oocyte. The features of their structural organization and the expression pattern of key genes significantly affect oocyte viability. Changes in the functional activity of the nucleus are often expressed in changes in the structure of nuclear bodies (NBs), including Cajal bodies (CBs). The diagnostic protein of CBs is coilin, which maintains their structural integrity. Using fluorescent and electron microscopy, we examined maternal aging-associated changes in coilin pattern in mouse CCs. We found that older mice had a decrease in the number of coilin-positive bodies, while external transcriptome data analysis revealed no significant changes in Coil and Smn1 gene expression. We hypothesized that the age-related dynamics of coilin-containing bodies are determined not by changes in the expression level of key components of these bodies, but by age-related changes in CC metabolism. Considering that CCs are a by-product of IVF protocols, making them available for analysis in sufficient quantities, age-related changes in the number and size of coilin-positive NBs in CCs may serve as a promising biomarker for assessing ovarian functional aging. Full article

A TiAlCrSiNbY coating was fabricated on γ-TiAl alloy by arc ion plating. The coating exhibits a dense, crack-free microstructure with a thickness of 5 ± 0.5 μm and strong interfacial bonding with the substrate. The characteristic power law correlations between mass gain and oxidation time were obtained for the uncoated and the coated samples at 850 °C with rate exponents of 2.38 and 2.14, respectively. After oxidation at 850 °C for 200 h, a continuous and dense oxide layer primarily composed of α-Al₂O₃ with a low oxidation reaction rate was formed, and the mass gain of the coated sample was 1/9 times that of the uncoated sample. Additionally, the addition of Cr and Nb in the TiAlCrSiNbY coating can increase the activity of Al and promoted the formation of stable and dense Al₂O₃ oxide films, the presence of a strong high-temperature stability Ti₅Si₃ phase inhibited the affinity of Ti and O, which maintained structural integrity and enhanced high-temperature oxidation resistance. Full article

This follow-up study investigates the long-term environmental sustainability and remediation outcomes of the UPPER (‘Urban Productive Parks for Sustainable Urban Regeneration’-UIA04-252) project in Latina, Italy, focusing on Nature-Based Solutions (NbS) applied to urban green infrastructure. By integrating proximal and satellite-based remote sensing methodologies, the research evaluates persistent improvements in vegetation health, soil moisture dynamics, and overall environmental quality over multiple years. Building upon the initial monitoring framework, this case study incorporates updated data and refined techniques to quantify temporal changes and assess the ecological performance of NbS interventions. In more detail, ground-based data from meteo-climatic, air quality stations and remote satellite data from the Sentinel-2 mission are adopted. Ground-based measurements such as temperature, humidity, radiation, rainfall intensity, PM10 and PM2.5 are carried out to monitor the overall environmental quality. Updated satellite imagery from Sentinel-2 is analyzed using advanced band ratio indices, including the Normalized Difference Vegetation Index (NDVI), the Normalized Difference Water Index (NDWI) and the Normalized Difference Moisture Index (NDMI). Comparative temporal analysis revealed consistent enhancements in vegetation health, with NDVI values significantly exceeding baseline levels (NDVI 2022–2024: +0.096, p = 0.024), demonstrating successful vegetation establishment with larger gains in green areas (+27.0%) than parking retrofits (+11.4%, p = 0.041). However, concurrent NDWI decline (−0.066, p = 0.063) indicates increased vegetation water stress despite irrigation infrastructure. NDMI improvements (+0.098, p = 0.016) suggest physiological adaptation through stomatal regulation. Principal Component Analysis (PCA) of meteo-climatic variables reveals temperature as the dominant environmental driver (PC2 loadings > 0.8), with municipality-wide NDVI-temperature correlations of r = −0.87. These multi-scale findings validate sustained NbS effectiveness in enhancing vegetation density and ecosystem services, yet simultaneously expose critical water-limitation trade-offs in Mediterranean semi-arid contexts, necessitating adaptive irrigation management and continued monitoring for long-term urban climate resilience. The integrated monitoring approach underscores the critical role of continuous, multi-scale assessment in ensuring long-term success and adaptive management of NbS-based interventions. Full article

In the present contribution, Hot-rolled and annealed ferritic stainless steel T4003 with three distinct Mo contents (0%, 0.1%, and 0.2%) served as the research subject. Weldability tests were implemented by means of gas metal arc welding. Coupled with microstructural characterization, mechanical property assessments, and electrochemical corrosion tests, the regulatory mechanism of Mo on the microstructure and properties of the HAZ was systematically elucidated. Results demonstrate that the influence of Mo content on the evolution of the coarse-grained region structure of heat affected zone becomes significant. The addition of 0.1% Mo refines the grains, increasing the fraction of lath martensite to 70–75% while limiting the maximum width of the coarse-grained zone to 0.64 mm. Meantime, the addition promotes the precipitation of (Nb, Ti, Mo) (C, N) composite carbonitrides, enhancing overall performance through synergistic grain refinement and second-phase strengthening. The sample with 0.1% Mo exhibits an average low-temperature impact energy of 16.3 J at −40 °C, with the highest Vickers hardness in the HAZ, favorable strength–plasticity synergy of the welded joint, and optimal corrosion resistance. The coarse-grained zone of the 0.2% Mo sample is dominated by coarse δ-ferrite and features a larger width, and the HAZ shows inferior mechanical properties and corrosion resistance. The precipitated phases in the 0.2% Mo segregate along the grain boundaries and distribute in a chain-like distribution, exacerbating the deterioration of material properties. These findings provide a technical reference for optimizing the composition design of T4003 ferritic stainless steel and ensuring its safe application in railway freight vehicles. Full article

Silica-based sorbents covalently modified with polyhedral boron clusters represent a promising platform for highly selective separation materials, yet robust and synthetically accessible immobilization protocols remain underdeveloped. In this work, novel sorbents based on commercially available silica gels functionalized with closo-dodecaborate anions were synthesized and systematically characterized. Two immobilization strategies were compared: direct nucleophilic addition of surface aminopropyl groups to the nitrilium derivative (Bu₄N)[B₁₂H₁₁NCCH₃] and sol–gel condensation of a pre-formed boron-containing APTES-derived silane. Covalent attachment via amidine bond formation was confirmed by solution and MAS ¹¹B NMR spectroscopy, IR spectroscopy, elemental analysis/ICP-OES, and SEM. The direct grafting route afforded a boron loading of 4.5 wt% (≈20% of the theoretical capacity), with the efficiency limited by electrostatic repulsion between anionic amidine fragments on the negatively charged silica surface, whereas the APTES route gave lower absolute loading (0.085 mmol/g) due to the low specific surface area of the coarse silica support. Despite the moderate degree of functionalization, the resulting boron cluster–modified silica gels are attractive candidates for specialized chromatographic applications, where the unique hydrophobic and dihydrogen-bonding properties of closo-dodecaborates may enable selective retention of challenging analytes and motivate further optimization of surface morphology and immobilization conditions. Full article