Search Results (4,478)

This review summarizes recent advances in intelligent spraying systems for precision agriculture. It focuses on the three interconnected components of perception, decision-making, and actuation, and compares the sensing characteristics of 2D planar field crops and three-dimensional orchard canopies. Particular emphasis is placed on evaluating the target recognition capabilities and physical limitations of machine vision, Light Detection and Ranging (LiDAR), ultrasound, and active fluorescence spectroscopy under complex field conditions. At the actuation level, the dynamic response characteristics of Pulse-Width Modulation (PWM), proportional control valves, and adaptive control algorithms are critically reviewed, revealing the influence mechanism of hydraulic transient phenomena, including water hammer effects induced by high-frequency valve switching, on droplet size distribution (DSD). The review further discusses the coupling effects between Unmanned Aerial Vehicle (UAV) airflow fields, Unmanned Ground Vehicle (UGV) motion disturbances, and spray deposition performance, and summarizes reported improvements in pesticide reduction, water conservation, and drift mitigation. Finally, the potential of cyber–physical systems (CPS) and digital twin-based frameworks for developing adaptive and closed-loop intelligent spraying systems is discussed to provide insights into future all-weather and autonomous agricultural operations. Full article

Ultra-high-pressure and extreme-pressure metrology plays a critical role in advanced manufacturing, geoscience, high-pressure physics, and frontier materials research. As pressure ranges extend from hundreds of MPa to several GPa and beyond, pressure generation and measurement are increasingly constrained by material strength, structural deformation, the state of pressure-transmitting media, sealing reliability, sensor drift, and incomplete traceability chains, imposing higher requirements on pressure metrology. This review systematically examines measurement technologies and traceability routes for ultra-high-pressure and extreme-pressure ranges. The development of controlled-clearance piston gauges is summarized, with emphasis on uncertainty reduction, range extension, and calibration automation. Drop-weight-based primary standards for dynamic pressure are also reviewed as an established route for the traceable calibration of high-amplitude, millisecond-scale hydraulic pressure pulses. Progress in secondary ultra-high-pressure standards is reviewed, including ultra-high-pressure gauges and piezoresistive, resonant, fiber-optic, and triboelectric sensors, with focus on range extension, high-accuracy measurement, environmental adaptability, and emerging pressure-sensitive mechanisms. Measurement methods for extreme pressure, including ruby fluorescence, Raman spectroscopy, X-ray diffraction, phase-transition points, and equations of state, are compared in terms of applicability and limitations. Current challenges in ultra-high-pressure and extreme-pressure metrology are further discussed, together with the prospects of quantum pressure sensing based on nitrogen-vacancy centers in nanodiamonds, providing a reference for future research and metrological infrastructure development. Full article

Three zinc(II) complexes based on 1-phenyl-3-methyl-4-acyl-5-pyrazolone were synthesized and characterized by elemental analysis, by X-ray crystallography and spectroscopy (UV-vis, fluorescence and IR). Crystallographic studies reveal that the complexes have a mononuclear structure in the solid state; however, intermolecular interactions combine the complexes into a 1D polymer chain. The complexes exhibit weak luminescence in the polycrystalline state and moderate emission in solutions and thin amorphous films. Thin films of the studied compounds were deposited on a glass substrate using thermal vacuum spraying, spin coating, and Langmuir-Blodgett technology and were studied using atomic force microscopy (AFM), X-ray spectroscopy, and fluorescence spectroscopy. Full article

The development of efficient photocatalysts for hydrogen production is a key challenge for sustainable energy technologies. In this study, strontium titanate (SrTiO₃) was synthesized via a citrate-assisted sol-gel method and subsequently modified by deposition-precipitation using nominal HAuCl₄ precursor concentrations of 1.0, 1.5, and 2.0 mM. The resulting materials were characterized by XRD, Raman spectroscopy, UV-Vis diffuse reflectance spectroscopy, SEM with EDS, and X-ray fluorescence (XRF). Au incorporation did not produce detectable changes in the SrTiO₃ crystalline phase or its optical band gap, which remained at 3.19–3.20 eV. The additional absorption band centered near 550 nm was consistent with the localized surface plasmon resonance of metallic Au nanoparticles. Microscopy indicated increasing surface coverage and aggregation at the highest nominal precursor concentration. Under irradiation with a low-pressure Hg lamp, all Au-containing materials presented substantially greater H₂ evolution than pristine SrTiO₃, whereas the comparatively small differences among the Au-modified samples indicated an apparent activity plateau across the evaluated concentration range. Because the Au-associated absorption band near 550 nm lies outside the main 254 nm emission of the lamp and the SrTiO₃ band gap remained mostly unchanged, the enhanced H₂ evolution is consistent with improved interfacial charge separation in the Au/SrTiO₃ system. A Schottky-junction-mediated pathway is proposed based on the observed activity trends and the electronic properties reported for Au/SrTiO₃ interfaces, rather than to a plasmonic or band-gap-tuning effect. The selected STO/Au 2.0 mM material retained approximately 97% of its initial apparent H₂ evolution rate after three consecutive cycles, indicating favorable short-term activity retention. Overall, this comparatively simple synthesis route provides a practical baseline for investigating the influence of nominal Au precursor concentration on H₂ evolution over SrTiO₃. Full article

Metformin is a widely used antidiabetic drug that may enter biological and environmental systems together with micro/nanoplastics; however, their combined effects on protein interactions and microbial responses remain insufficiently understood. This study investigated how polyethylene terephthalate micro/nanoplastics (PET MNPs) influence metformin interactions with bovine serum albumin (BSA) and the subsequent responses of Escherichia coli and Staphylococcus aureus. BSA–metformin systems were conditioned with three PET MNP loads and increasing metformin concentrations. The resulting particle-depleted filtrates were evaluated using fluorescence spectroscopy, ultraviolet–visible spectroscopy, the Bradford assay, Rayleigh light scattering, turbidity, dithiothreitol-based oxidative potential, and reactive oxygen species (ROS) measurements. Bacterial growth, superoxide dismutase activity, glutathione-related thiol antioxidant response, lipid peroxidation, ROS generation, and biofilm formation were also assessed. PET MNP conditioning altered the fluorescence responses of tryptophan and tyrosine, modified BSA-associated absorbance, and produced non-linear changes in protein accessibility, aggregation-related scattering, turbidity, and oxidative indicators. The bacterial responses were species-specific. Escherichia coli showed increased bacterial growth under several exposure conditions, whereas Staphylococcus aureus exhibited reduced growth following metformin addition, particularly at the highest PET MNP load. Staphylococcus aureus also showed consistently elevated biofilm formation and a pronounced transient ROS increase under the high-PET, low-metformin condition. These findings indicate that upstream PET MNP conditioning can modify the physicochemical and biological properties of the filter-passing BSA–metformin phase, leading to concentration-dependent and species-specific bacterial responses. Full article

To evaluate how composted agricultural and forestry organic materials function as components of horticultural growing media, a pot experiment was conducted with chrysanthemum (Chrysanthemum morifolium Ramat.) grown in a cinnamon-soil-based medium. The composted material, produced from chestnut shells, chicken manure, and spent mushroom substrate, was incorporated at 0%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, and 50% (v/v). Water-extractable dissolved organic matter (WE-DOM) was characterized by excitation-emission matrix fluorescence spectroscopy coupled with parallel factor analysis (EEM-PARAFAC), together with the fluorescence index (FI), biological index (BIX), humification index (HIX), and fluorescence regional integration (FRI). Growing-medium physicochemical properties, chrysanthemum traits, and an entropy-weighted comprehensive evaluation were also assessed. Compost amendment increased soil organic matter (SOM), dissolved organic carbon (DOC), total nitrogen, and total phosphorus, lowered pH, and was associated with improved porosity and water-retention characteristics. FI ranged from 1.810 to 2.371 and exceeded 1.9 at amendment rates of 30–35%, suggesting a greater contribution from microbially derived DOM. BIX, HIX, and P_V,n/P_III,n were generally higher in amended treatments than in the control, although their responses were non-monotonic across amendment rates, suggesting greater contributions from recently produced DOM and stronger humification-related fluorescence signals. EEM-PARAFAC resolved five fluorescent components. C1, C2, C3, and C5 were predominantly humic-like, whereas C4 displayed both protein-like and humic-like features. With increasing amendment rate, the relative contributions of C1–C4 generally increased, whereas that of C5 declined, suggesting a shift from the native soil fluorescence profile toward a more complex DOM composition influenced by compost inputs and subsequent biological transformation. Chrysanthemum height, stem diameter, flower number, and biomass were generally more favorable at amendment rates of 30–40%. The entropy-weighted evaluation yielded the highest overall response score at 30%, while the 35% treatment also maintained a high score. Considering WE-DOM fluorescence characteristics, growing-medium properties, and plant performance together, a volumetric amendment rate of 30–35% represents a relatively favorable range for the tested composted material under the present pot-experiment conditions. Full article

Two-dimensional GaS_xTe_1−x alloy nanosheets with different compositions were synthesized by chemical vapor deposition using GaS and GaTe powders as precursors. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) analyses confirmed their sheet-like morphology and the uniform distribution of S and Te, while Raman and photoluminescence measurements revealed composition-dependent vibrational and emission characteristics. Te-rich samples exhibited position-dependent emission ranging from the red to the near-infrared region, whereas increasing the S content gradually shifted the emission toward the blue-green region. Among the synthesized samples, GaS_0.9Te_0.1 showed a relatively stable photoluminescence peak near 520 nm and was therefore selected as a fluorescent powder for latent fingermark development. Its performance was evaluated on glass, stainless steel, plastic, and ceramic surfaces and compared with that of silver powder, gold powder, and commercial red fluorescent powder. GaS_0.9Te_0.1 produced clear fluorescent ridge patterns and strong background contrast, particularly on glass, plastic, and white ceramic. The mean contrast across the four substrates reached 25.83, exceeding that of the reference powders. These results demonstrate that GaS_xTe_1−x nanosheets possess tunable optical properties and that GaS_0.9Te_0.1 is a promising fluorescent material for latent fingermark development on non-porous surfaces. Full article

1-Deoxynojirimycin (DNJ), a well-characterized α-glucosidase inhibitor, remains an important target for dose-reduction and formulation strategies. In the present study, we evaluated the individual and combined α-glucosidase inhibitory activities of nine dietary flavonoids with DNJ, quantified synergistic effects using the combination index (CI) method, and elucidated the molecular mechanism through integrated enzyme kinetics, multi-spectroscopic techniques and molecular docking. (+)-Catechin exhibited the strongest inhibitory activity (IC₅₀ = 33.7 ± 2.7 μM), and its combination with DNJ produced synergistic inhibition across all doses (CI < 0.7). Kinetic analysis confirmed that DNJ acted as a competitive inhibitor, while (+)-catechin functioned as a non-competitive inhibitor. Fluorescence quenching assays revealed that (+)-catechin pre-incubation increased the binding affinity of DNJ to α-glucosidase by 393%. Circular dichroism spectroscopy showed that (+)-catechin induced a marked β-sheet-to-α-helix conformational conversion, and co-incubation of both inhibitors produced more secondary structural changes than either inhibitor alone. Molecular docking further confirmed their distinct binding sites. These findings demonstrate that (+)-catechin synergistically potentiates DNJ activity through allosteric conformational modulation, providing an experimental basis for optimizing DNJ-containing formulations. Full article

Microplastics (MPs) have been reported in commercial beverages, but substantial differences in study design make direct comparisons difficult. This non-systematic, focused narrative review critically synthesizes a purposively selected core set of 17 particle-count studies published from 2020 to 2026 on soft drinks, beer, wine, tea, coffee, juices, energy drinks, and related beverages, while considering recent complementary thermal-analysis evidence. Data were compared for study location, beverage type, analytical method, abundance, particle size, morphology, color, polymer composition, and packaging. Fourier-transform infrared spectroscopy-based methods were most common; Raman spectroscopy, fluorescence microscopy, scanning electron microscopy, and laser direct infrared imaging were used in selected studies. Reported soft-drink concentrations ranged from approximately 0.30 particles/L to 166 ± 62 particles/100 mL (1660 ± 620 particles/L), but these values cannot support a geographic ranking because minimum particle-size thresholds, confirmation criteria, blank corrections, sample volumes, and reporting units differed. Fibers and fragments were the dominant morphologies, and polyethylene terephthalate, polyethylene, polypropylene, and polyamide were frequently identified. Findings from beverages packaged in glass and aluminum, as well as plastic, indicate that source water, ingredients, processing equipment, filtration, closures, ambient deposition, and packaging can all contribute. Current intake estimates describe potential particle ingestion rather than absorbed dose or toxicological impact. Because current data largely reflect analytical sensitivity rather than true contamination gradients, this review demonstrates that reliable cross-study exposure assessments currently remain associated with considerable uncertainty, and this uncertainty will be difficult to resolve until particle-count data are normalized to harmonized size thresholds and paired with mass-based thermal analyses. Full article

This study presents a comparative evaluation of the wear performance of three hot-work tool steels—WCLV (1.2344), Uddeholm Unimax, and Uddeholm QRO 90 Supreme—for die forging applications. The materials were characterized in terms of hardness and bulk chemical composition using Vickers hardness testing and X-ray fluorescence spectroscopy. Tribological behavior was investigated using ball-on-disc tests, while industrial performance was assessed by analyzing forging punches after the production of 16,250 components. Surface degradation was quantified using optical profilometry and three-dimensional roughness parameters. Measured hardness values were 591 HV for WCLV, 622 HV for QRO 90 Supreme, and 639 HV for Uddeholm Unimax. The average friction coefficients were 0.88, 0.92, and 0.77, respectively. Unimax also exhibited the lowest volumetric wear, reaching 0.04683 mm³ (R19 mm) and 0.03384 mm³ (R22 mm), compared with 0.08646–0.13095 mm³ for WCLV and 0.09598–0.13635 mm³ for QRO 90 Supreme. This corresponds to approximately 45–70% lower wear relative to the other steels. Industrial trials confirmed improved surface stability of Unimax punches after service. The observed trends are consistent with differences in alloying content and the expected microstructural response associated with chromium and molybdenum additions. Overall, Uddeholm Unimax demonstrated the most favorable balance of hardness, friction behavior, and wear resistance. Full article

Cow milk adulteration in plant-based milk alternatives (PBMAs) raises authenticity and safety concerns, particularly for consumers with dairy allergies or lactose intolerance. This study evaluated the laboratory-scale feasibility of excitation–emission matrix (EEM) fluorescence spectroscopy combined with chemometric and machine-learning approaches for detecting and quantifying cow milk adulteration in almond and oat milk alternatives used as model matrices. Three independent preparation batches were produced for each PBMA matrix using one almond source, one oat source, and one commercial cow milk product, with cow milk concentrations ranging from 0 to 100% (v/v) and 2.5% as the lowest non-zero adulteration level. Parallel factor analysis identified 270 and 350 nm as informative excitation wavelengths, and the corresponding emission profiles were analyzed using principal component analysis, data-driven soft independent modeling of class analogy (DD-SIMCA), partial least squares regression (PLSR), random forest regression (RFR), and a one-dimensional convolutional neural network (1D-CNN). DD-SIMCA effectively rejected most adulterated samples, although target-class sensitivity was based on resubstitution because only three authentic spectra were available per condition. Under batch-grouped cross-validation, the best performance within the 0–50% adulteration range was obtained by PLSR for oat milk at 350 nm ($R_{\mathrm{GCV}}^2=0.877$, ${\mathrm{RMSE}}_{\mathrm{GCV}}=6.12\%$, and ${\mathrm{RPD}}_{\mathrm{GCV}}=2.91$), while RFR showed more consistent performance across matrix–wavelength combinations. The 1D-CNN exhibited greater variability and did not consistently outperform conventional models. These findings support the laboratory-scale feasibility of fluorescence-based screening for the investigated almond and oat matrices, while further validation using additional product sources, independently prepared batches, commercial samples, and lower adulteration levels is required before broader application to PBMA products can be established. Full article

Seed quality profoundly affects productivity, marketability, and food security, yet conventional evaluation methods are destructive, slow, and unsuited to high-throughput screening. Non-destructive techniques, being rapid, non-invasive, and capable of measuring multiple indicators, have therefore gained substantial momentum. This review critically surveys the principles, applications, and limitations of major non-destructive techniques for seed quality assessment. Near-infrared spectroscopy (NIRS) enables fast, simultaneous multi-component analysis in portable formats, but its shallow penetration and poor sensitivity to subtle chemical shifts restrict single-seed vigor tests. Hyperspectral imaging (HSI) uniquely merges spectral with spatial data to map composition and surface defects, though large data volumes, high cost, and limited portability hinder practical use. Machine vision offers low-cost, high-throughput external sorting but captures only surface traits and is illumination-sensitive. X-ray/CT imaging visualizes internal cracks and insect damage, yet radiation safety and bulky hardware preclude field deployment. Complementary tools (NMR, electronic nose, Raman, dielectric, fluorescence, acoustic) address niche needs but face stability, sensitivity, or dimensionality trade-offs. Future breakthroughs demand multi-sensor data fusion, deep learning optimization, and ruggedized low-cost hardware. Bridging laboratory innovation and industrial reality requires concurrent algorithmic, optical, and engineering advances, ultimately transforming seed testing into a reliable, intelligent, and deployable ecosystem. Full article

This study developed a composite rejuvenator comprising recycled polyethylene wax (PREW), waste cooking oil (WCO), and epoxidized soybean oil (ESO) activated by the tertiary amine catalyst BDMA to improve the intermediate-temperature rejuvenation of aged SBS-modified asphalt binder. The binder was subjected to combined rolling thin-film oven and pressure aging vessel aging. Conventional tests, rotational viscosity, bending beam rheometer, multiple stress creep recovery, fluorescence microscopy, and Fourier transform infrared spectroscopy were used to evaluate macroscopic, rheological, and microstructural properties. Aging hardened and embrittled the binder, increased softening point and viscosity, reduced penetration and ductility, and disrupted the polymer-rich phase. PREW reduced flow resistance and retained relatively high-temperature structural stability, whereas WCO improved flexibility and flowability, although excessive softening impaired high-temperature stability. ESO/BDMA treatment was accompanied by changes in oxygen-containing functional group-related absorption regions and improved apparent connectivity of the SBS-rich phase. Among the tested temperatures, 120 °C provided the best overall balance among the evaluated properties, satisfying low-temperature stress-relaxation requirements while limiting high-temperature creep deformation. These results identify 120 °C as the preferred treatment temperature for the PREW/WCO/ESO-BDMA rejuvenation system. Full article

We review a theoretical and experimental programme with the aim of understanding two intimately related fundamental phenomena in biophysics: (i) the classical analogue of Fröhlich phonon condensation in macromolecules driven out of thermal equilibrium and (ii) the consequent activation of long-range resonant electrodynamic intermolecular forces. Both phenomena are underpinned by explicit Hamiltonian models. The first is derived by applying the time-dependent variational principle (TDVP) to the quantum Wu–Austin model, producing a fully classical Hamiltonian in action-angle variables whose nonlinear rate equations exhibit a nonequilibrium phase transition: the channelling of supplied energy into the lowest-frequency collective mode. The second is grounded in a classical electrodynamic Hamiltonian for two coupled oscillating dipoles whose normal-mode structure predicts long-range (∼$1/r^3$) resonant interactions, absent at thermal equilibrium but activated by out-of-equilibrium collective oscillations. We also discuss a complementary Hamiltonian approach that connects Fröhlich’s rate equations directly to Hamilton’s equations of motion, clarifying the role of bath-mediated nonlinear coupling and the conditions for strong condensation at room temperature. In addition, the TDVP is applied to a Davydov–Holstein–Fröhlich Hamiltonian describing electron–phonon motion along the backbone of a specific DNA sequence and its cognate restriction enzyme, EcoRI: the time-domain Fourier cross-spectrum of the resulting electron currents exhibits a sharp co-resonance peak for the canonical recognition sequence that disappears upon randomisation, providing a sequence-specific electrodynamic signature of DNA–protein recognition. Experimental evidence from THz near-field spectroscopy, fluorescence correlation spectroscopy, and direct observation of protein clustering is reviewed in relation to these theoretical predictions. The results establish a coherent physical picture suggesting that metabolic energy supply can play a role in driving macromolecules into coherently oscillating states that activate selective, distance-reaching electrodynamic forces capable of contributing to the organisation of biochemical reactions in living matter. Full article

The potential of zein gels as functional delivery platforms for resveratrol (RESV), a natural polyphenol with antiamyloidogenic action but low systemic bioavailability, is explored by a combination of spectroscopic (circular dichroism, infrared, fluorescence, UV–Vis), calorimetric (differential scanning microcalorimetry) and rheological methods. Molecular docking is also applied for mapping the interaction sites and forces between native zein and RESV. Zein–RESV interactions in solution are systematically evaluated to understand the structural changes from a soluble protein–polyphenol system to a gel network. The concentration-dependent effect of RESV on the structural and thermal stability of zein is investigated in relation to the mechanical and functional properties of zein–RESV gels. It is shown that RESV acts as a promoter of zein aggregation, with a more pronounced effect obtained at a RESV:zein 1:1 molar ratio. By increasing the α-helix content, RESV induces a more ordered zein secondary structure in solution. In gel, the three-dimensional zein network is disrupted by hydrophobic and hydrogen-bonding interactions with RESV. Fluorescence spectra of zein gels point to conformational changes upon interaction that are confirmed by infrared spectroscopy. A significant viscoelastic deformation of the gel occurs when the RESV:zein molar ratio increases to 4:1. The RESV:zein 1:1 gel network demonstrates optimal viscoelastic properties for the release of RESV, following a biphasic transition from diffusion to matrix-controlled release. The findings of this study contribute to the structural design of zein-based systems for encapsulating and delivering bioactive compounds. Full article