Search Results (2,296)

(1) Background: Water, comprising about 70–80% of cellular mass, is the most abundant constituent of living cells. Upon exposure to ionizing radiation, water undergoes radiolysis, generating a variety of reactive species, including free radicals and molecular products. Among these, hydroxyl radicals (^•OH) are particularly damaging due to their very high reactivity and their capacity to induce oxidative injury to vital biomolecules such as DNA, membrane lipids, and proteins. From a radiation-chemical perspective, this study investigates the selective scavenging ability of molecular hydrogen (H₂) toward ^•OH radicals, with the aim of evaluating its potential as an antioxidant and radioprotective agent; (2) Methods: We employed our Monte Carlo track chemistry simulation code, IONLYS-IRT, to model the time-dependent yields of ROS in a neutral, aerated aqueous environment. The simulations included varying concentrations of dissolved H₂ and, for comparison, cystamine—a well-known sulfur-containing radioprotector and antioxidant. Irradiation was simulated using 300 MeV protons, chosen to mimic the radiolytic effects of low linear energy transfer (LET) radiation, such as that of ⁶⁰Co γ-rays or fast (>1 MeV) electrons; (3) Results: Our simulations quantitatively demonstrated that H₂ selectively scavenges ^•OH radicals. Nevertheless, its scavenging efficiency was consistently lower than that of cystamine, which produced a faster and more pronounced suppression of ^•OH due to its higher reactivity and superior radical-quenching capacity; (4) Conclusions: Molecular hydrogen offers several unique advantages, including low toxicity, high diffusivity, selective scavenging of ^•OH radicals, and well-documented anti-inflammatory effects. Although it is less potent than cystamine in terms of radical-scavenging efficiency, its excellent safety profile and biological compatibility position H₂ as a promising radioprotector and antioxidant for therapeutic applications targeting radiation-induced oxidative stress and inflammation. Full article

This simulation-based theoretical study addresses a critical gap by jointly assessing the technical performance and long-term economic sustainability of Solar Domestic Hot Water (SDHW) systems in economically volatile, import-dependent regions. Focusing on a fully operational system in a 700-bed dormitory at Middle East Technical University, Northern Cyprus Campus, TRNSYS 17 simulations were combined with a 15-year (2010–2024) cost trend analysis considering currency depreciation and construction price escalation. Results demonstrate that collector fluid temperatures exceeded 80 °C from April to October, maintaining domestic hot water above 60 °C for over seven months annually and reducing auxiliary heating demand by approximately 50%, translating into substantial annual energy savings. Economically, system component costs rose by 26–75 times, with circulation pumps showing the steepest increase (75×), highlighting vulnerabilities in import-dependent supply chains. Despite these cost escalations, the region’s high solar irradiation enables a competitive long-term investment profile, with potential payback periods remaining attractive under supportive policy frameworks. The originality of this work lies in its dual-focus methodology integrating performance modeling with economic resilience analysis, providing actionable insights for policymakers, designers, and investors in Mediterranean and similar climates seeking to balance renewable energy adoption with financial viability. Full article

Cavitation has been widely explored to enhance physical and chemical processes across various applications. This study aimed to model the key characteristics of a cavitation jet, induced by a triangular-orifice nozzle, using both experimental and numerical methods. Optical instrumentation, a pressure transducer and the Reynolds-Averaged Navier–Stokes (RANS) equations were employed. Optical instrumentation and high-speed photography detected the two-phase flow generated by water vaporization, revealing a mean decay pattern. Irradiance fluctuations and photographic evidence provided results about the light transmission dynamics through cavitating jets. Pressure fluctuations exhibited similar growth and decay, supporting optical instrumentation as a viable method for assessing cavitation intensity. Experimental data showed a strong relationship between irradiance and flow rate (R² = 0.998). This enabled the correlation of the standard deviation of instantaneous pressure measurements and normalized flow rate (R² = 0.977). Furthermore, vapor volume fraction and normalized flow rate reached a correlation coefficient of 0.999. On the simulation side, the SSG-RSM turbulence mode showed better agreement with experimental data, with relative deviations ranging from 2.1% to 6.6%. The numerical results suggest that vapor jet length is related to vapor fraction through a power law, enabling the development of new equations. These results demonstrated that anisotropic turbulence modeling is essential to reproduce experimental observations compared to mean flow properties. Based on the agreement between the numerical model and the experimental data for mean flow quantities, a formulation is proposed to estimate the jet length originating from the nozzle, offering a predictive approach for cavitating jet behavior. Full article

We report a low-cost protocol and platform for whole-abdomen 3D dynamic contrast-enhanced ultrasound (DCE-US) imaging in mice using a clinical matrix-array transducer. Background/Objectives: This platform addresses common limitations of preclinical ultrasound systems. In particular, these systems often lack real-time volumetric and molecular imaging capabilities. Methods: Using a modified silicone cup and water bath configuration, mice with dual subcutaneous tumors were imaged in vivo on a clinical EPIQ 7 system equipped with an X6-1 transducer. Results: Intravenous administration of targeted microbubbles enabled high-resolution, contrast-mode 3D imaging at multiple time points. Volumetric reconstructions captured both tumors and surrounding anatomy in a single scan, while time–intensity curves and Differential Targeted Enhancement (DTE) analysis revealed greater microbubble uptake in irradiated tumors, consistent with elevated P-selectin expression. Conclusions: This standardized imaging platform enables whole-abdomen molecular DCE-US in preclinical studies, facilitating intra-animal comparisons of vascular and molecular features across lesions or organs. Full article

This study investigates the electro-thermal transient response of a photovoltaic–thermal (PV/T)–heat pump system under dynamic disturbances to optimize operational stability. A dynamic model integrating a PV/T collector and a heat pump was developed by the transient heat current method, enabling high-fidelity simulations of step perturbations: solar irradiance reduction, compressor operation, condenser water flow rate variations, and thermal storage tank volume changes. This study highlights the thermal storage tank’s critical role. For V_tank = 2 m³, water tank volume significantly suppresses the water tank and PV/T collector temperature fluctuations caused by solar irradiance reduction. PV/T collector temperature fluctuation suppression improved by 46.7%. For the PV/T heat pump system in this study, the water tank volume was selected between 1 and 1.5 m³ to optimize the balance of thermal inertia and cost. Despite PV cell electrical efficiency gains from PV cell temperature reductions caused by solar irradiance reduction, power recovery remains limited. Compressor dynamic performance exhibits asymmetry: the hot water temperature drop caused by speed reduction exceeds the rise from speed increase. Load fluctuations reveal heightened risk: load reduction triggers a hot water 7.6 °C decline versus a 2.2 °C gain under equivalent load increases. Meanwhile, water flow rate variation in condenser identifies electro-thermal time lags (100 s thermal and 50 s electrical stabilization), necessitating predictive compressor control to prevent temperature and compressor operation oscillations caused by system condition changes. These findings advance hybrid renewable systems by resolving transient coupling mechanisms and enhancing operational resilience, offering actionable strategies for PV/T–heat pump deployment in building energy applications. Full article

The conventional recycling of spent lithium-ion batteries (LIBs) is hindered by high energy consumption and severe environmental pollution. In this study, a novel method utilizing high-frequency electromagnetic radiation was proposed to process the black mass derived from spent NCM-LIBs, significantly reducing both energy consumption and chemical reagent usage. Conductive carbon black was introduced as an electromagnetic-wave-absorbing additive to improve the electromagnetic energy into thermal energy conversion efficiency during electromagnetic radiation. As a result, the decomposition and reduction of NCM materials can be completed within just 10 min at a microwave power of 500 W. Following electromagnetic irradiation, lithium was efficiently extracted via simple water leaching, achieving an extraction efficiency of 88.24%. Furthermore, a microwave heating device based on traveling-wave propagation was developed. Unlike conventional small-scale microwave systems that employ resonant cavities, this design enables improved heating uniformity, higher efficiency, and greater scalability for industrial microwave-assisted chemical processes. Full article

This paper is a result of the search for design assumptions for a sensor to detect oil dispersed in the sea waters (oil-in-water emulsions). Our approach is based on analyzing changes in the underwater solar radiance (L) field caused by the presence of oil droplets in the water column. This method would enable the sensor to respond to the presence of oil contaminants dispersed in the surrounding environment, even if they are not located directly at the measurement point. This study draws on both literature sources and the results of current numerical modeling of the spread of solar light in the water column to account for both downward and upward irradiance (Es). The core principle of the analysis involves simulating the paths of a large number of virtual solar photons in a seawater model defined by spatially distributed Inherent Optical Properties (IOPs). The IOPs data were taken from the literature and pertain to the waters of the southern Baltic Sea. The optical properties of the oil used in the model correspond to crude oil extracted from the Baltic shelf. The obtained results were compared with previously published spectral analyses of an analogous polluted sea model, considering vertical downward radiance, vertical upward radiance, and downward and upward irradiance. It was found that the optimal wavelength ratio of 555/412, identified for these quantities, is also applicable to scalar irradiance. The findings indicate that the most effective way to determine this index is by measuring it using a sensor with its window oriented in the direction of upward-traveling light. Full article

Ultrahigh dose rate (UHDR) radiotherapy, also known as FLASH radiotherapy (FLASH-RT), has shown potential for increasing tumor control while sparing normal tissue. In parallel, gold nanoparticles (GNPs) have been extensively explored as radiosensitizers due to their high atomic number and ability to enhance the generation of reactive oxygen species (ROS) through water radiolysis. In this study, we investigate the synergistic effects of UHDR electron beams and GNP-mediated radiosensitization using Monte Carlo (MC) simulations based on the Geant4-DNA code. A spherical water phantom with embedded GNPs of varying sizes (5–100 nm) was irradiated using pulsed electron beams (100 keV and 1 MeV) at dose rates of 60, 100, and 150 Gy/s. The chemical yield of ROS near the GNPs was quantified and compared to an equivalent water nanoparticle model, and the yield enhancement factor (YEF) was used to evaluate radiosensitization. Results demonstrated that YEF increased with smaller GNP sizes and at lower UHDR, particularly for 1 MeV electrons. A maximum YEF of 1.25 was observed at 30 nm from the GNP surface for 5 nm particles at 60 Gy/s. The elevated ROS concentration near GNPs under FLASH conditions is expected to intensify DNA damage, especially double-strand breaks, due to increased hydroxyl radical interactions within nanometric distances of critical biomolecular targets. These findings highlight the significance of nanoparticle size and beam parameters in optimizing ROS production for FLASH-RT. The results provide a computational basis for future experimental investigations into the combined use of GNPs and UHDR beams in nanoparticle-enhanced radiotherapy. Full article

This study evaluates the energy performance and efficiency of a low-concentration photovoltaic (CPV) system integrated with a phase change material (PCM), referred to as the CPV–PCM system, which stores and delivers thermal energy for building applications. A paraffin-based PCM with a melting point range of 58–60 °C was selected to align with typical building temperature requirements. The system was tested over three consecutive days in July at Al Ain, United Arab Emirates, under extreme climatic conditions (2100 W/m² solar irradiance, 35–45 °C ambient temperature), and its performance was compared to standard CPV and traditional tracked PV systems. The results demonstrate that PCM integration significantly enhances thermal regulation, reducing CPV peak temperatures by 38 °C (from 123 °C to 85 °C) and average temperatures by 22 °C (from 88 °C to 66 °C). The CPV–PCM system achieved a total energy efficiency of 60%, doubling that of standard CPV (30%) and tracked PV (25%), with cumulative electrical and thermal energy outputs of 370 Wh and 290 Wh, respectively. This dual electrical–thermal output enables the system to meet building heating demands, such as ~200–300 Wh/m² for domestic hot water and ~100–150 Wh/m² for space heating in United Arab Emirates winters, positioning it as a sustainable solution for energy-efficient buildings in arid regions. The findings underscore the advantages of PCM-based thermal control in CPV systems for hot climates, addressing gaps in prior studies focused on moderate conditions. Future research should explore long-term durability, optimized containment techniques, and alternative PCMs to further improve performance. Full article

The tension in the relationship between water and energy seriously restricts the harmonious coexistence between man and the ecological environment. The solar-powered interface evaporation technology emerging in recent years has shown good application prospects in high-salt wastewater treatment for achieving the zero-discharge treatment of wastewater. In this review, advanced solar-driven interfacial evaporation is primarily focused on its mechanisms, photothermal materials optimization, and the structure of solar evaporators for salt removal. The high wide-spectrum solar absorption rate of photothermal materials determines the total energy that can be utilized in the evaporation system. The light-to-heat conversion capacity of photothermal materials directly affects the efficiency and performance of solar interface evaporators. We highlight the microstructures enabled by the nanophotonic designs of photothermal material-based solar absorbers, which can achieve highly efficient light harvesting across the entire solar irradiance spectral range with weighted solar absorptivity. Finally, based on current research, existing problems, and future development directions for high-salt wastewater evaporation research are proposed. The review provides insights into the effective treatment of high-salt wastewater. Full article

Understanding the growth dynamics and ecological constraints of Porphyra spp. is essential for optimizing sustainable seaweed aquaculture. However, most existing models lack physiological detail and exhibit limited performance under variable environmental conditions. This study developed a mechanistic Dynamic Energy Budget (DEB) model to simulate structural biomass accumulation, carbon and nitrogen reserve dynamics, and blade area expansion of Porphyra under natural environmental conditions in Korean coastal waters. The model incorporates temperature, irradiance, and nutrient availability (NO₃⁻ and CO₂) as environmental drivers and was implemented using a forward difference numerical scheme. Field data from Beein Bay were used for model calibration and validation. Simulations showed good agreement with the observed biomass, reserve content, and blade area, with root-mean-square error (RMSE) typically within ±10%. Sensitivity analysis identified temperature-adjusted carbon assimilation and nitrogen uptake as the primary drivers of growth. The model was further used to estimate dynamic carrying capacity, revealing seasonal thresholds for sustainable biomass under current farming practices. Although limitations remain—such as the exclusion of reproductive allocation and tissue loss—the results demonstrate that DEB theory provides a robust framework for modeling Porphyra aquaculture. This approach supports scenario testing, spatial planning, and production forecasting, and it is adaptable for ecosystem-based management including integrated multi-trophic aquaculture (IMTA) and climate adaptation strategies. Full article

This study evaluated the qualitative and quantitative performance of lettuce (cv. Romana) grown using different cultivation systems under Mediterranean greenhouse conditions equipped with photoluminescent glass panels. Five systems were compared: outdoor soil (PSO), indoor soil (PSI), aeroponic (A), hydroponic with inorganic nutrients (HSN), and hydroponic with organic nutrients (HSO). Morphological, physiological, and quality parameters were measured alongside solar irradiance and extended PAR. The results showed that aeroponics significantly outperformed other systems in fresh weight (52.7 g), photosynthetic pigments, and carotenoids, while HSO showed the lowest yield and quality. Although PSO had the highest antioxidant activity and phenolic content, it exhibited poor yield due to lower water use efficiency and light-induced stress. The PCA analysis highlighted distinct groupings among systems, with A linked to yield and pigment concentration, and PSO associated with antioxidant traits. Despite a 44.8% reduction in solar radiation inside the greenhouse, soilless systems—especially aeroponics—proved effective for maintaining high productivity and quality. These findings support the integration of soilless systems and photoluminescent technologies as sustainable strategies for high-efficiency lettuce production in controlled environments. Full article

Background: Recently, extensive use of antibiotics has increased the amount of antibiotic residues in the natural water environment. Methods: This study presents an experimental investigation into the degradation of penicillins, tetracyclines, streptomycin and chloramphenicol in aqueous solutions when exposed to 1 MeV accelerated electrons with doses of 0.1, 1, 3 and 7 kGy using HPLC-HRMS analysis. Results: It was found that electron beam irradiation with a dose of 7 kGy ensures 98–99% removal of antibiotics, with the initial concentrations ranging from 15 mg/L to 30 mg/L depending on the class of antibiotic. The mathematical model proposed in the study, which estimates the dose dependencies of the relative concentrations of antibiotics and their degradation products in aqueous solutions, reveals different decomposition rates of antibiotics of different classes due to the different radiosensitivities of antibiotics. It has been found that tetracycline has a considerably higher radiation–chemical yield compared to the other antibiotics when exposed to accelerated electrons. Conclusions: Using density functional theory in combination with the mathematical model, we have developed a novel approach to establishing a quantitative irradiation marker of antibiotic degradation as a result of irradiation, which involves finding the degradation product whose formation requires a minimum number of ionization events. Using such an approach, it is possible to establish the extent of antibiotic degradation in water after irradiation with different doses and find the optimal irradiation doses for industrial water treatment. Full article

Electrochemical sensors have been developed based on polyethylene terephthalate track-etched membranes (PET TeMs) modified by photograft copolymerization of N-vinylformamide (N-VFA) and trimethylolpropane trimethacrylate (TMPTMA). The modification, structure and properties of the modified PET TeMs were thoroughly characterized using scanning electron microscopy (SEM) and atomic force microscopy (AFM), thermogravimetric analysis (TGA), Fourier-transform infrared (FTIR) spectroscopy, gas permeability measurements and contact angle analysis. Optimal membrane modification was achieved using C = 10% (N-VFA), 60 min of UV irradiation and a UV lamp distance of 10 cm. Furthermore, the modified membranes were implemented in a two-electrode configuration for the determination of Eu³⁺, Gd³⁺, La³⁺ and Ce³⁺ ions via square-wave anodic stripping voltammetry (SW-ASV). The sensors exhibited a linear detection range from 10⁻⁷ M to 10⁻³ M, with limits of detection of 1.0 × 10⁻⁶ M (Eu³⁺), 6.0 × 10⁻⁶ M (Gd³⁺), 2.0 × 10⁻⁴ M (La³⁺) and 2.5 × 10⁻⁵ M (Ce³⁺). The results demonstrated a significant enhancement in electrochemical response due to the grafted PET TeMs-g-N-PVFA-TMPTMA structure, and the sensor showed practical applicability and consistent performance in detecting rare earth ions in tap water. Full article

Curcumin is a natural active ingredient with various health benefits but suffers from poor water solubility, chemical instability, and rapid metabolism. This study developed a novel composite gel, blueberry leaf polysaccharide–xanthan gum (BLP-XG), for the protection and delivery of curcumin. The experimental results demonstrate that the formation of stable composite gel networks is predominantly facilitated by hydrogen bonding and electrostatic interactions between BLP and XG components. In comparison with single-component systems, composite gels exhibit superior structural homogeneity and density, as well as higher thermal stability, viscoelasticity, and predominantly elastic solid behavior. The BLP-XG composite gel achieved the highest curcumin encapsulation rate of 84.23% when the BLP concentration was 2.0%. The composite gel system effectively retained curcumin in the gastric juice and released it in the small intestine. Furthermore, the presence of BLP in the composite gel inhibited curcumin degradation under UV irradiation. This study establishes the research foundation for the development of efficient and stable delivery systems to protect and deliver curcumin and extends the use of blueberry leaf polysaccharides in food and pharmaceutical applications. Full article