Search Results (512)

Holographic synthetic aperture radar (HoloSAR) enables 360° three-dimensional reconstruction by incoherently stacking tomographic subaperture images. However, after conventional subaperture-wise TomoSAR reconstruction and non-coherent integration, the resulting 3D imagery suffers from severe dynamic range imbalance due to angle-dependent scattering responses: wide-angle strong scatterers are repeatedly amplified, whereas narrow-angle weak structures are buried below the noise floor. To address this post-processing challenge, we propose a joint statistical filtering framework operating on the reconstructed subaperture-domain 3D images that fuses the coefficient of variation, inter-subaperture correlation, and spectral entropy with adaptive discriminative-power weighting; target screening is then performed via a Gaussian mixture model-based Bayesian optimal threshold. For pixels classified as weak targets, a percentile-matching energy-balancing transformation is applied to adaptively rescale their energy to the main-target reference level while preserving relative amplitude relationships. Experiments on real-world Ku-band UAV circular SAR data demonstrate that the proposed method effectively compresses the dynamic range, suppresses background noise, and recovers weak narrow-angle structures that are lost in traditional non-coherent superposition, yielding more complete and interpretable HoloSAR 3D reconstructions. Quantitative evaluation on Ku-band UAV circular SAR data demonstrates that the proposed method improves the Target-to-Background Ratio by 0.7 dB (to 11.2 dB), achieves a Background Suppression Ratio of −5.2 dB, increases the Structural Completeness Index by 156% (to 1428.1), and compresses the original dynamic range imbalance, which exceeds 50 dB, while preserving scene physical realism (ENL ≈ 7.4 × 10⁻³). Full article

The non-isothermal crystallization behavior of CF/PEEK composites during the cooling stage of processing significantly influences their final properties. However, the effect of PEEK melt fluidity on the crystallization kinetics and crystal morphology of CF/PEEK composites under varying cooling rates remains to be elucidated. This study employed differential scanning calorimetry (DSC) combined with crystallization kinetic models including Avrami and Mo equations to analyze the non-isothermal crystallization process, while wide-angle X-ray scattering (WAXS) characterized the crystal morphology. The results indicate that with increasing PEEK melt fluidity, the crystallinity of CF/PEEK composites rose from 22.2% to 25.93% at a cooling rate of 5 °C/min, accompanied by an enhanced crystallization rate. Mechanical testing revealed that the mechanical properties improved with increasing fluidity: the tensile and flexural strengths increased from 264.8 MPa and 413.3 MPa for CF/PEEK20 to 299.1 MPa and 476.5 MPa for CF/PEEK146, respectively. Furthermore, as the PEEK melt fluidity increased, the dominant factor governing crystallization behavior shifted from chain structural stability to molecular chain mobility, and ultimately to nucleation capability. Full article

The formation of stereocomplex (SC) crystallites in poly(L-lactide) (PLLA)/poly(D-lactide) (PDLA) blends has attracted significant attention due to its potential to enhance the performance of biodegradable polymer films. In this study, the effect of solvent evaporation kinetics on the crystallization behavior, microstructure, and functional properties of PLLA/PDLA blend films was systematically investigated. Films with various blend ratios were prepared under open-lid (fast evaporation) and closed-lid (slow evaporation) conditions. Differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD), and small-angle X-ray scattering (SAXS) analyses revealed that slow solvent evaporation significantly promotes stereocomplex formation, particularly at the equimolar (50:50) composition, resulting in a higher degree of crystallinity and a more compact structure compared to fast evaporation conditions. These structural changes were directly correlated with improved functional properties. The optimized PLLA/PDLA (50:50) films exhibited a substantial reduction in water vapor permeability from 22.7 to 3.11 g·mm/m²·day·kPa (~86% decrease) and a marked decrease in microbial growth, as evidenced by reduced total plate count (TPC) values compared to neat polymers. The enhanced barrier performance and reduced microbial proliferation were attributed to the reduced free volume and increased tortuosity associated with densely packed stereocomplex crystallites, as supported by DSC and WAXD results. These findings demonstrate the importance of solvent evaporation kinetics in tailoring structure–property relationships to control stereocomplex formation and multiscale structural organization, providing a practical strategy for biodegradable packaging films. Full article

The purpose of this study was to examine the utilization of 0–45 μm aluminum hydrate fraction (gibbsite) manufactured by Alum SA Tulcea, as a precursor in the hydrothermal synthesis process of nanosize boehmite from gibbsite suspensions. Furthermore, the use of the produced material as adsorbent of lanthanum (III) ions was investigated using aqueous solutions. Thermogravimetric analysis (TG), Fourier Transform InfraRed Spectroscopy (FT-IR), Wide-Angle X-Ray Scattering (WAXS), and atomic force microscopy (AFM) were used to demonstrate the preparation of the required material. Additionally, the material point of zero charge (pHpzc) and material specific surface (using BET approach) were evaluated. By conducting adsorption studies, the specific parameters for the lanthanum adsorption process were evaluated. The effects of pH, the ratio of adsorbent material to La(III) quantity from aqueous solution, contact time, and La(III) initial concentration were also assessed. Based on the obtained experimental data, it was proved that the maximum adsorption capacity of 97.7 mg/g was obtained for a solid:liquid ratio = 0.1 g:25 mL, pH between 3 and 6, temperature of 298 K, and contact time of 90 min. The studied adsorption process is most effectively described by the Sips model, suggesting an intricate interaction among the adsorbent material and La (III) ions. The prepared adsorbent exhibited a good desorption capacity (higher than 93%) when 20% HCl was used for desorption. Full article

Background: Platinum-based chemotherapy, including cisplatin and carboplatin, is widely used to treat various cancers, including ovarian cancer. However, its clinical application is limited by dose-limiting toxicities and resistance, with a poor 5-year overall survival rate for ovarian cancer (35–40%). In this study, we used ionisable lipids and developed pH-responsive lipid nanoparticles (LNPs) to address platinum-resistance in ovarian carcinoma. Methods: Cisplatin was loaded into three LNP systems containing monoolein (MO) and synthetic cationic ionisable lipids (OE-Mo, OA-Py, and OA-Pi) dispersed in Pluronic F-127 with 0.9% NaCl. Cisplatin-loaded LNPs (Cis-OE-Mo-NP, Cis-OA-Py-NP, and Cis-OA-Pi-NP) were characterised for size, zeta potential, and internal mesophase structure. Encapsulation efficiencies were determined via HPLC after removing free drug by ultrafiltration. In vivo efficacy was tested using cisplatin-resistant human patient-derived xenograft (PDX) models. Results: The LNPs were well dispersed with particle size of 219–250 nm and a drug loading of ~1.2 mg/mL. Encapsulation efficiencies were 62%, 59%, and 64%, for Cis-OE-Mo-NP, Cis-OA-Py-NP, and Cis-OA-Pi-NP, respectively. Small angle X-ray scattering (SAXS) results showed that the LNPs are pH responsive with structural transitions from a cubic to a hexagonal phase at an acidic pH. Among the tested formulations, Cis-OA-Py-NP resulted in the most significant reduction in tumour volume by ~60% compared to treatment with cisplatin alone. However, they also showed significant toxicity, including >10% weight loss and gross lung and kidney damage, as confirmed by histology. Conclusions: These findings highlight the potential of Cis-OA-Py-NP in reducing tumour volume but underscore the need for further optimisation to improve safety and therapeutic applicability. Full article

This study investigates the formation mechanism of non-doped cubic lithium lanthanum zirconium oxide (c-LLZO) nanofibers using in situ synchrotron X-ray scattering techniques. Electrospun polymer precursor nanofibers were annealed at temperatures up to 800 °C, enabling real-time tracking of phase transitions via simultaneous small-angle X-ray scattering (SAXS), wide-angle X-ray scattering (WAXS), and evolved CO₂ gas analysis. The results reveal a three-step transformation pathway: polymer decomposition, formation of La₂Zr₂O₇ (LZO), and direct conversion of LZO to c-LLZO without intermediate tetragonal phases detected within the sensitivity of our in situ WAXS measurement. Cryo-electron energy loss spectroscopy (EELS) further elucidates the role of lithium diffusion, showing Li enrichment at fiber surfaces and Li deficiency in the interior, which stabilizes the cubic phase. This Li segregation effect in nanostructured LLZO materials extends beyond the previously reported size effect. This work advances the understanding of c-LLZO formation mechanisms and provides practical insights for optimizing synthesis routes to achieve phase-pure c-LLZO for solid-state battery applications. Full article

This study investigates the effect of chemical modification of xylite—a fraction derived from Polish lignite—using succinic anhydride (SA) on the morphology and mechanical performance of isotactic polypropylene (iPP) composites. Xylite was incorporated at loadings of 1, 10, and 25 wt% and in two particle size ranges (40–63 µm and 63–125 µm), with and without SA (0.5 and 2 wt%). The composites were characterized by wide-angle X-ray scattering (WAXS), Fourier-transform infrared spectroscopy (FTIR), and tensile testing to evaluate crystallinity (X_c), β-phase content (k_β), and mechanical properties. Unmodified xylite reduced crystallinity (X_c down to ~37%) and significantly decreased ductility, with elongation at break strongly negatively correlated with filler content (r ≈ −0.68), indicating poor dispersion and weak interfacial adhesion. In contrast, SA addition (0.5–2 wt%) partially restored crystallinity (up to ~48%) and increased stiffness (Young’s modulus up to 2120 MPa), while altering β-phase content. FTIR analysis indicated reduced intermolecular hydrogen bonding between xylite surface hydroxyl groups in the presence of SA, consistent with interfacial chemical interactions, likely via esterification. The β-phase content showed a moderate positive correlation with xylite loading (r = +0.43) and a negative correlation with elongation at break (r = −0.46), suggesting that excessive β-phase formation may reduce toughness. Larger particles (63–125 µm) provided slightly improved elongation at break and stiffness. Overall, SA acts as both a compatibilizer and a morphology-directing agent, enabling precise control of the stiffness–ductility balance and crystalline structure in iPP/xylite composites. These results establish chemically modified lignite-derived fillers as a viable strategy for engineering cost-efficient polyolefin materials with tunable structure–property relationships, offering strong potential for scalable industrial implementation. Full article

Plant extracts are widely used as natural pesticides, cosmetic ingredients, and in pharmaceutical applications. However, their poor water solubility and stability limit their usability. Lipid nanoparticles (LNPs) offer an effective encapsulation strategy to overcome these challenges. This study demonstrates the encapsulation of three representative substances from these industries: quercetin as a pesticide, irones as a cosmetic ingredient, and nucleic acids for pharmaceutical use. Ultrasonic treatment was used for the encapsulation of quercetin and irones, and a concept for continuous encapsulation in a plug flow reactor was proposed for process intensification. Inline multi-angle light scattering and dynamic light scattering measurements proved effective for real-time monitoring and enabled the replacement of traditional batch measurements. In the pharmaceutical area, mRNA-based therapies require LNP encapsulation to prevent nucleic acid degradation. Plant-based β-sitosterol was used as an alternative helper lipid to cholesterol, resulting in an average particle diameter of 72 nm and an encapsulation efficiency of 91%, comparable to commercial formulations such as the Comirnaty vaccine. Furthermore, a novel process model based on population balances was developed to simulate the entire manufacturing process, from rapid mixing in a T-mixer to particle stabilization via buffer exchange during diafiltration. By applying a quantitative and distinctive model validation workflow, the model was shown to be as accurate and precise as the experimental data, enabling its use as a digital twin for autonomous continuous operation. In summary, this study contributes to reducing the facility footprint and cost of goods through the implementation of continuous processing and model-based control. This approach improves productivity by 20% and reduces process time by a factor of two. Full article

Fully polarimetric SAR provides richer scattering information than single-polarisation imaging, but multichannel sparse image formation can be computationally and memory demanding, especially when channels are processed jointly. In our previous work, we introduced Orthogonal Matching Pursuit 2D Fully Polarimetric (OMP2D-FP), a greedy reconstruction algorithm that enforces a shared spatial support across polarimetric channels while exploiting a separable 2D formulation to avoid vectorisation and reduce computational burden and memory footprint relative to vectorised OMP-based formulations. In this paper, we extend its validation to real measurements and further develop its theoretical foundations by recasting the atom-selection step as a detection–estimation problem, thereby defining a cumulative objective function (COF) design space that enables the incorporation of disturbance statistics and prior knowledge into sparse recovery. Experiments on fully polarimetric SAR data of a T-72 tank over a wide range of aspect angles, SNR levels, and measurement percentages show that joint support selection improves reconstruction fidelity and polarimetric information preservation over independent per-channel processing, with particularly clear gains under challenging conditions. Preliminary applications of the COF framework (a whitening COF incorporating polarimetric clutter statistics and a mask-based COF incorporating spatial prior knowledge) yield encouraging results, motivating further systematic investigation of adaptive COF designs. Full article

X-ray techniques provide powerful, non-destructive tools for structural characterization in semiconductor manufacturing and advanced packaging. Their strong penetration capability and sensitivity to multiple contrast mechanisms enable the investigation of lattice structure, strain, defects, interfaces, and elemental distribution across a wide range of length scales. As semiconductor devices evolve toward three-dimensional architectures and heterogeneous integration, there is an increasing demand for characterization approaches capable of probing complex, buried, and multi-scale structures in a consistent manner. In this review, we present a systematic overview of X-ray characterization techniques for advanced semiconductor systems, including diffraction-based methods, small-angle scattering, computed tomography, X-ray fluorescence, and spectroscopic approaches. These techniques are discussed in terms of the type of structural, morphological, and compositional information they provide, their applicable length scales, and their strengths and limitations in addressing key challenges such as thin films, high-aspect-ratio structures, buried interfaces, and full wafers. Particular attention is given to the complementary nature of different X-ray modalities and their roles in addressing practical metrology problems. The limitations associated with resolution, model dependence, and data interpretation are also outlined. Finally, emerging opportunities in laboratory X-ray sources, synchrotron-based methods, and integrated characterization strategies are briefly discussed. This review aims to provide a unified perspective for understanding and integrating X-ray techniques, offering insights into their roles in addressing the growing complexity of next-generation semiconductor devices. Full article

Titanium dioxide (TiO₂) is a versatile material that exhibits a high refractive index, strong light-scattering capability, effective UV-absorption, wide band gap semiconductor behavior (3.0–3.2 eV), and excellent chemical stability. Owing to this unique combination of properties, TiO₂ is widely used in applications such as cosmetic and healthcare products, architectural and automotive coatings, and photocatalytic degradation of environmental pollutants. In photocatalytic applications, the crystal structure, phase composition and electronic properties of TiO₂ play a critical role in determining its performance. In the present study, TiO₂ nanotubes were synthesized by anodization of Ti° coatings deposited via a semi-industrial arc-PVD process. A post-anodization heat treatment was carried out at 430 °C for 1 h to promote the formation of the anatase phase within the TiO₂ nanotube structures. The structural characterization of the synthesized film was performed using X-ray diffraction (XRD) and Rietveld refinement. This methodology enabled the identification of the formed oxide phases, structure, and crystalline, confirming the formation of mixed oxides in the coating. To address the difficulty of refinement of these crystalline phases, the Le Bail method was applied. This refinement strategy allowed the identification of the crystalline phases that are present in the Ti_xO_y coating, including a hexagonal structure characteristic of α-Ti (space group P63/mmc, No. 194), the tetragonal anatase TiO₂ (space group I41/amd, No. 141) phase, and the trigonal Ti₂O₃ phase (space group R-3/c No. 167). Key crystallographic parameters such as lattice constants, bond lengths and angles, crystallite sizes, unit cell distortion and electron density were systematically evaluated for each phase. In addition, the Wyckoff positions and interatomic distances of the constitutive atoms were calculated, providing a comprehensive description of the TiO₂+Ti₂O₃/Ti° crystallographic system. The topographic and surface oxidation states were recorded by using profilometry and X-ray photoelectron spectroscopy, respectively. Full article

Multistatic sonar provides enhanced target detection in complex underwater environments. The wide-angle bistatic scattering characteristics of targets, particularly the bistatic reflection coefficients, are important for evaluating system performance and designing acoustic absorbing coatings. However, obtaining full-angle experimental measurements is challenging, and conventional finite-element simulations become computationally prohibitive for large structures, high frequencies, or exhaustive angle sweeps. To overcome these challenges, a fast wide-angle scattering prediction method for acoustically coated plates is proposed. The method constructs a scattering transfer matrix from the surface mesh and retrieves the equivalent source density from a small subset of scattered-pressure samples, enabling reconstruction of the full-angle scattering field and rapid extraction of reflection coefficients. The approach is demonstrated on both rigid and coated plates, with predictions compared against finite-element calculations. The results demonstrate that the proposed method accurately reproduces the bistatic reflection coefficients, including non-linear dispersion effects and interference fringes, across a wide frequency band from 100 Hz to 5 kHz. Compared to traditional FEM sweeps, this method significantly reduces computational time while maintaining high accuracy, providing an efficient tool for the design of acoustic stealth materials and laying a foundation for rapid target strength prediction of complex targets using the Planar Element Method. Full article

LED diffuse-illumination systems are widely used in industrial inspection and real life because of their scattering properties. However, there has been little research on secondary optical designs for diffuse illumination. Considering the need for diffuse light in real life and work, combined with existing specular-reflection technology, this study proposes a design method for a combined-freeform-surface illumination system with specular and diffuse reflections. Considering that a separate diffusing device cannot effectively control the diffusion area of the light source, the unique properties of the specular-reflective device were utilized in this study. First, the specular-reflection device directs the light from the central portion of the LED to the diffuse-reflection device, and the light collected is then redistributed by the diffuse-reflection device. Two mathematical models were established according to the light-emitting angle of the LED, which corresponded to two freeform surfaces. In addition, when evaluating the uniformity of the target-plane illumination, a set of constraint equations was added to obtain the diffuse freeform surface contour of the target plane. Finally, the ratio of the diameter to the thickness of the resulting illumination system exceeded six, and the illumination uniformity increased to over 56% (with a uniformity improvement ratio of ≥6% compared to traditional single-freeform-surface systems and ≥10% compared to integrating sphere systems). It is specifically designed for industrial precision inspection scenarios, has higher illumination uniformity than other diffuse illumination systems, and has better compactness, making it suitable for high-precision inspection lighting applications. Full article

Energy-Dispersive X-ray Diffraction (EDXRD) employs a polychromatic (white) X-ray beam and an energy-discriminating detector at a fixed scattering geometry to measure diffracted intensity as a function of photon energy. This technique enables the rapid acquisition of diffraction data over a wide range of d-spacings without mechanical scanning of the scattering angle, making it particularly valuable for time-resolved, bulk-penetrating, and operando studies. In this review, we provide a comprehensive overview of EDXRD, covering the fundamental principles and underlying physics, experimental methodologies and data analysis workflows, synchrotron white-beam implementations compared to monochromatic approaches, detector strategies, parameter optimization for accurate and efficient measurements, and representative applications in high-pressure science and battery research. Finally, we discuss current challenges and future prospects, including advances in detector technology, machine learning-assisted spectral analysis, and the development of standardized, automated EDXRD systems. Full article