Search Results (2,311)

Optical fiber sensors (OFSs) have emerged as essential tools in the monitoring of physical, chemical, and bio-medical parameters in harsh situations due to their high sensitivity, electromagnetic interference (EMI) immunity, and long-term stability. However, the current literature contains scattered information in most reviews regarding individual sensing technologies or domains. This study provides a structured exploratory review in a novel inter-family analysis of both intrinsic and extrinsic configurations by analyzing more than 23,000 publications between 2019 and 2025 in five key domains: industry, medicine and biomedicine, environmental chemistry, civil/structural engineering, and aerospace. The analysis aims to critically discuss how functional principles/parameters and methods of interrogation affect the applicability of different OFS categories. The results reveal leading trends in the use of techniques like the use of fiber Bragg gratings (FBG) and distributed sensing in high-accuracy conditions or the rising role of extrinsic sensors in selective chemical situations and point out new approaches in areas like Artificial Intelligence (AI)- or Internet of Things (IoT)-integrated sensors. Further, this synthesis not only connects pieces of knowledge but also defines the technological barriers in terms of calibration cost and standardization: this provides strategic insight regarding future research and the scalability of industry deployment. Full article

The incorporation of native Amazonian fruits into dairy products has increased due to their ability to improve technological, sensory, nutritional, and biological properties. Therefore, this study aimed to evaluate the impact of cupuassu (Theobroma grandiflorum) pulp on the chemical, physical, and sensory characteristics of fermented milk, using a central rotational composite design with two factors (sugar and cupuassu pulp). Our results are presented as response surfaces, showing that cupuassu pulp is positively associated with the examined parameters (pH, titratable acidity, total soluble solids, total phenolic compounds, syneresis, and water retention capacity). The analysis suggested a promising formulation containing 27.8% cupuassu pulp and 8.6% sugar. The pulp and this promising formulation were characterized by pH, titratable acidity, total soluble solids, proximate composition, and bioactive compounds (total phenolic compounds (TPC) and antioxidant activity). The physicochemical stability of the beverage was monitored over 28 days. Sensory acceptance and purchase intention for the promising formulation were also evaluated. Cupuassu contributed to an increase in soluble solids, while pH and titratable acidity remained stable during storage. Additionally, cupuassu pulp increased the total phenolic content and enhanced the beverage’s antioxidant activity. Sensory analysis showed that adding cupuassu pulp positively influenced all evaluated attributes (83% acceptance) and was associated with a favorable purchase intention. Incorporating cupuassu pulp into fermented milk proved to be technologically feasible and sensorially acceptable, meeting the demand for innovative dairy beverages with functional and sensory benefits. Full article

The integration of silica nanoparticles (NS) into cementitious composites has emerged as a promising strategy to refine the microstructure and enhance concrete performance. Beyond their chemical role in accelerating hydration and promoting additional C–S–H gel formation, silica nanoparticles act as physical fillers, reducing porosity and improving interfacial bonding within the matrix. These dual effects result in a denser and more resilient composite, whose mechanical and dynamic responses differ from those of conventional concrete. However, studies addressing the vibrational and modal behavior of nano-reinforced concretes, particularly under elastic and viscoelastic foundation conditions, remain limited. This study investigates the dynamic response of NS-reinforced concrete slabs using a refined quasi-3D plate deformation theory with five (05) unknowns. Different foundation configurations are considered to represent various soil interactions and assess structural integrity under diverse supports. The effective elastic properties of the nanocomposite are obtained through Eshelby’s homogenization model, while Hamilton’s principle is used to derive the governing equations of motion. Navier’s analytical solutions are applied to simply supported slabs. Quantitative results show that adding 30 wt% NS increases the Young’s modulus of concrete by about 26% with only ~1% change in density; for simply supported slender slabs, this results in geometry-dependent increases of up to 18% in the fundamental natural frequency. While the Winkler and Pasternak foundation parameters reduce this frequency, the damping parameter of the viscoelastic foundation enhances the dynamic response, yielding frequency increases of up to 28%, depending on slab geometry. Full article

Groundwater wells are essential for sustaining biodiversity in arid and hyper-arid regions. Wells are easily affected by external disturbances, particularly in hyper-arid regions like the Siwa Oasis, where the environmental variables influencing groundwater communities remain understudied. This study assessed the quality of several groundwater wells and agricultural drains based on the physical, chemical and hydrochemical parameters. The results classified the wells and drains into three distinct groups: (1) highly mineralized, carbonated systems with high concentrations of potassium, calcium, sodium, magnesium, chloride, and sulfate, and an average electrical conductivity (EC) of 12.01 mS/cm; (2) low-mineralized wells with an average EC of 2.15 mS/cm; and (3) a moderate one averaging 7.77 mS/cm. The major ions were dominated by Na⁺ (59.3%) and Mg²⁺ (26.8%) for cations, and Cl⁻ (79.1%) and SO₄²⁻ (13.4%) for anions in meq/L. Collectively, the evaluation based on total dissolved solids (TDS), sodium percentage (Na%), sodium adsorption ratio (SAR), and the US Salinity Laboratory (USSL) diagram revealed that about 80% of the analyzed wells are unsuitable for irrigation, with only three wells (W03, W12, and W16) deemed suitable for drinking. These findings confirmed a critical vulnerability of the oasis ecosystem. The uncontrolled and extensive use of finite, non-renewable aquifers for agricultural and other purposes is directly exacerbating water salinization and soil sodicity, posing a threat to the future sustainability of the oasis’s water resources. Full article

Cross-linked polyethylene (PEX) is very stable, both chemically and mechanically. This makes its waste difficult to process. A very promising approach is slow pyrolysis catalyzed by hematite (α-Fe₂O₃). Such pyrolysis was carried out on a large scale (feedstock of 38 kg, catalyst amount of 2 wt.%, heating rate of 4 K min⁻¹, end temperature of 435 °C, delay at the end temperature several hours) and provided an oil containing both liquid (up to C₁₇) and solid hydrocarbons (>C₁₇). Thus, the oil obtained can be a source of valuable chemicals, solvents, and paraffin, and/or used as a clean liquid fuel and/or as a source of lubricants. Pyrolysis of PEX also yielded energy gas (12 wt.%) and solid carbonaceous residue (15 wt.%) for further use. The process mass balance and parameters (temperature, heating rate, dwell time, catalyst amount), composition, and chemical (elemental analysis, XRF, GC-MS, GC, distillation curve) and physical (viscosity, density, higher and lower heating value) properties of the oil, gas, and solid carbonaceous residue obtained are presented and discussed. The main product of the proposed technology is oil with a yield of almost 73 wt.%. The by-products are energy gas (12 wt.%) and solid carbonaceous residue (15 wt.%). The results obtained showed that the proposed technology successfully recycles difficult-to-process PEX with a process efficiency of 70%. Full article

As a core candidate material for indium-free transparent conductive oxides, tin dioxide (SnO₂) thin films are gradually replacing indium tin oxide (ITO) and becoming a research focus in the field of optoelectronic devices, thanks to their excellent physicochemical stability, wide bandgap characteristics, and abundant tin resource reserves. This review focuses on SnO₂ thin films. Firstly, it elaborates on the tetragonal rutile crystal structure characteristics of SnO₂ and the transparent conductive mechanism based on oxygen vacancies and doping elements to regulate free electron concentration, while clarifying the key parameters for evaluating their transparent conductive properties. Subsequently, it systematically summarizes the research progress in preparing SnO₂ transparent conductive thin films via physical methods and chemical methods in recent years. It compares the microstructure and transparent conductive properties of thin films prepared by different methods, and analyzes the regulatory laws of preparation processes, doping types, and film thickness on their optoelectronic properties. Furthermore, this work supplements the current application status of SnO₂ thin films in devices. Meanwhile, the core performance differences between indium-free tin-based thin film devices and ITO-based devices are compared. Finally, we have summarized the advantages and challenges of physical and chemical methods in the preparation of SnO₂ thin films. It also forecasts the application potential of interdisciplinary integration of physical–chemical methods and the development of new doping systems in the preparation of high-performance SnO₂ transparent conductive thin films. This review aims to provide theoretical guidance and technical references for the selection and process optimization of SnO₂ transparent conductive thin films in fields such as photovoltaic devices and flexible optoelectronic equipment. Full article

Zearalenone (ZEN) is a thermostable, lipophilic, non-steroidal estrogenic mycotoxin produced by Fusarium spp. that persistently contaminates food and feed. Its strong estrogenic activity and resistance to conventional detoxification strategies pose significant threats to food safety and human and animal health. Conventional physical and chemical degradation methods often compromise nutritional quality and leave toxic residues. Here we report the engineering of a novel Clonostachys rosea lactone hydrolase, Cr2zen, for efficient ZEN degradation in Pichia pastoris under mild conditions. Native Cr2zen exhibited a protein concentration of 0.076 mg/mL, achieving a degradation rate of approximately 17.9% within 30 min, with kinetic parameters of K_m 75.9 µM and V_max 0.482 µmol/L/s at 30 °C and pH 8.0. By integrating signal peptide screening and codon optimization, we identified Ser-Cr2 as the most effective variant, achieving a rapid 81.53% degradation of 10 ppm ZEN under mild conditions. Fed-batch cultivation in a 7.5 L bioreactor resulted in high cell densities of OD₆₀₀ 332.8 for Ser-Cr2 and 310.8 for Oser-Cr2, with extracellular protein concentrations of 0.62 and 0.79 g/L, respectively. The results demonstrate that signal peptide engineering and codon optimization substantially improved the production of lactone hydrolase in P. pastoris. This study establishes a scalable ZEN degradation under mild conditions in P. pastoris and outlines a strategy to integrate protein and process engineering for enhanced enzymatic mycotoxin degradation. Full article

Indoor Air Quality (IAQ) is a major public health concern, as prolonged exposure to indoor environments can significantly affect users’ well-being. In this context, the research proposes a sampling protocol, developed in compliance with ISO 16000 principles, for the assessment of key chemical and physical parameters influencing air quality in inpatient rooms. These spaces host fragile users, while also requiring adequate protection for healthcare staff. Referring to the scope of the paper, the study outlines a comprehensive methodology for monitoring selected volatile organic compounds (VOCs) and microclimatic factors—temperature and relative humidity—using passive samplers and/or active sensors. The protocol also integrates outdoor measurements to better understand the contribution of internal emission sources. Monitoring activities are scheduled over one year, with regular sampling campaigns (at least one week per month) to analyze seasonal variations and long-term trends. The flexible structure of the protocol allows it to be adapted to different research objectives and types of healthcare facilities. Overall, the proposed approach provides a replicable framework for assessing IAQ in healthcare settings and identifying the main factors affecting indoor environmental performance. This supports improvements in both environmental quality and health protection within healing spaces. Full article

Chemical contaminants in drinking water represent a widespread threat to human health, making water quality monitoring an essential mitigation measure. This study aimed to assess the quality of drinking water by conducting comprehensive multi-year seasonal monitoring at seven distribution points in central Romania, determining the spatial and temporal trends of relevant physical parameters (pH and electrical conductivity) and chemical contaminants (NO₂, NO₃, NH₄, Cl, and SO₄). The pollution degree was evaluated using the pollution index and the overall pollution assessment index. The principal component analysis attributed over 60% of water quality variance to NO₂, NO₃, and NH₄ pollution, linked to incomplete nitrification or external loading, such as agricultural practices. Additionally, a human health risk assessment was performed according to U.S. EPA guidelines, calculating the chronic daily intake, hazard quotient, and hazard index for nitrogen compounds via oral and dermal exposure pathways for both adults and children. The results showed significant seasonal fluctuations in nitrogen compounds and electrical conductivity. The pollution indices classified the water bodies across a spectrum from “light” to “significant” pollution degrees. The health risk assessment revealed that NO₃ was the primary risk driver, with hazard index values exceeding the threshold of one in specific locations and seasons, indicating potential adverse health effects, particularly for children. Full article

Conservatively perturbed equilibrium (CPE) experiments yield transient concentration extrema that surpass steady-state equilibrium values. A physics-informed neural network (PINN) framework is introduced to simulate these over-equilibrium dynamics in linear chemical reaction networks without reliance on extensive time-series data. The PINN incorporates the reaction kinetics, stoichiometric invariants, and equilibrium constraints directly into its loss function, ensuring that the learned solution strictly satisfies physical conservation laws. Applied to three- and four-species reversible mechanisms (both acyclic and cyclic), the PINN surrogate matches conventional ODE integration results, reproducing the characteristic early concentration extrema (maxima or minima) in unperturbed species and the subsequent relaxation to equilibrium. It captures the timing and magnitude of these extrema with high accuracy while inherently preserving total mass. Through the physics-informed approach, the model achieves accurate results with minimal data and a compact network architecture, highlighting its parameter efficiency. Full article

Chromium nitride (Cr-N) coatings fabricated by physical vapor deposition (PVD) have gained significant interest in the field of surface protection with the exceptional hardness, robust adhesion to substrates, and superior wear resistance. The mechanical properties of Cr-N coatings are predominantly determined by their chemical composition, phase structure, and microstructure. The selection of deposition technique and regulation of process parameters, such as N₂ flow rate, play a crucial role in optimizing coating performance. This review systematically summarizes recent research advancements in PVD-fabricated Cr-N coatings with a specific focus on both monolayer and multilayer architectures. It explores the impact of process parameters on the hardness, adhesion strength, and tribological properties. Furthermore, it outlines the design strategies and fabrication methodologies for high-performance Cr-N coatings. Results indicate that the mechanical properties of monolayer Cr-N coating are primarily governed by the process parameters. As for multilayer coatings, the incorporation of ductile Cr layers can enhance the coating-substrate adhesion strength and wear resistance while preserving a relatively high hardness. This study aims to provide a theoretical foundation and technical reference for future research and applications of the Cr-N coating material system. Full article

Palladium, a non-toxic platinum-group metal, is widely used in catalysis, electronics, hydrogen storage, and chemical industries because of its excellent physical and chemical properties. However, given that the number of palladium-producing countries is limited, recycling is considered essential for ensuring a stable and sustainable global supply. Here, I describe a simple and efficient method for palladium recovery from electronic waste (e-waste) using Enterobacter oligotrophicus CCA6^T. To clarify biomineralization capacity, the role of electron donors in modulating biomineralization capacity was examined. Findings showed that formic acid was the most effective donor, enhancing the relative recovery rate to 44% compared to 23% without electron donors. Transmission electron microscopy analysis revealed palladium particles (1–10 nm) distributed across the cell wall, periplasmic space and cytoplasm, confirming active biomineralization rather than passive biosorption. Moreover, based on a comparison with the biomineralization mechanism of Escherichia coli, the biomineralization mechanism of E. oligotrophicus CCA6^T was estimated . Reaction parameters were then optimized by testing the effects of formic acid concentration, reaction temperature, and reaction pH. Under optimized conditions, the relative recovery rate exceeded 99% within 6 h using 40 mg/L palladium. When this method was applied to a metal dissolution solution prepared from e-waste , a recovery rate of 94% was achieved from trace concentrations (36 µg/L), and palladium loss from bacteria after the palladium recovery test was negligible (<0.01%). Taken together, these results demonstrate that biomineralization using E. oligotrophicus CCA6^T could potentially be applied to the recovery of palladium from e-waste, particularly for trace-level concentrations where conventional methods are ineffective. Full article

The analysis of the physical and chemical properties of blackcurrant (Ribes nigrum L.), strawberry (Fragaria ananassa Duchesne ex Weston) and raspberry (Rubus idaeus L.) seeds recovered from pomace—food processing waste—was carried out. The weight of the one thousand seeds, their dry weight, swelling properties, and color in the CIE L*a*b* space, as well as the percentage of basic chemical components, i.e., protein, carbohydrate (including total dietary fiber, insoluble fiber, and soluble dietary fiber), fat, and ash were determined. Polyphenols content and antioxidant activity was determined. In addition, the amounts of individual phenolic compounds, fatty acids, and amino acids, as well as macro and micro-nutrients, were identified and analyzed. The potential usefulness of raspberry seeds as a rheology modifier of cosmetics and food products was estimated due to the high content of mucilage and swelling index similar to linseed and a favorable color with a high value of the b* parameter (22.1) corresponding to yellow color simultaneously with high luminescence (L* = 59.4). Oils obtained from all tested seeds are potentially useful in cosmetic preparations due to the high content of n-6 acids (50.4–71.5%), and oils from strawberry and raspberry seeds as a result of containing n-3 acids, respectively; 30.5–32.3% may be beneficial for dietary supplementation. In addition, the dietary values of the tested seeds are emphasized by the high content of dietary fiber (53.1–63.1%), antioxidant properties (the highest for blackcurrant) and the presence of phenolic compounds such as procyanidin derivatives, catechins (raspberry), quercetins and kaempferols (blackcurrant), and pelargonidin (strawberry). Full article

To address the issues of resistance and food safety stemming from the overuse of chemical fumigants in stored-grain pest control, this study aimed to systematically optimize the insecticidal process of pulsed electric field (PEF) treatment on Tribolium castaneum (T. castaneum) and to investigate its electro-neurotoxicity mechanism. Single-factor experiments were used to determine parameter ranges, and response surface methodology (RSM) was employed to analyze the effects of electric field strength, pulse frequency, and treatment time. The finite element method (FEM) was used to simulate the physical field distribution, and acetylcholinesterase (AChE) activity was measured to explore neurotoxicity. The results indicated that electric field strength, pulse frequency, and treatment time all had highly significant effects (p < 0.0001), with electric field strength being the primary factor. The optimal process parameters were determined to be: electric field strength of 26 kV/cm, pulse frequency of 20 kHz, and treatment time of 140 s. Under these conditions, the predicted and actual mortality rates were both 100%, and this efficacy was validated in rice samples. Simulation confirmed that PEF achieves physical targeting through a “tip effect” on the insect’s nerve endings; mechanism tests demonstrated that PEF treatment significantly inhibited AChE activity (p < 0.01). This study confirms the “electro-neurotoxicity” mechanism of PEF, providing theoretical support for this green physical control technology. Full article

This study develops a numerical model based on a multi-physics coupled finite element method to predict the carbonation depth of hardened alkali-activated slag under accelerated carbonation curing conditions. Drawing on existing literature data, the chemical composition and porosity of alkali-activated slag at different ages were determined under non-carbonation conditions, supported by thermodynamic and kinetic analyses of alkali activation reactions. A differential equation governing CO₂ diffusion—incorporating diffusion rate, diffusion coefficient, carbonation reaction rate, and related parameters—was established using Fick’s second law. The influence of humidity and carbonation degree on the reaction rate was quantified, and a correlation between carbonation degree and porosity was derived through thermodynamic analysis. These equations were solved numerically in a two-dimensional domain to predict carbonation depth over time. The results demonstrate that the proposed model, using only raw material composition and curing conditions, achieves reasonable accuracy in predicting carbonation depth. Full article