Search Results (854)

The current state of the art research, and latest engineering technology application in the synthesis of the aragonite crystalline phase of calcium carbonate is presented here. Aragonite crystalline products are highly valuable in selected industries, such as medical and personal care, and in food additives using MgCl₂ as a chemical inducer. The outcome of this literature review provides the outlook of the available research whitespace opportunity in optimizing the current process parameters and in ensuring that sustainable and economically feasible continuous production of aragonite products could be achieved. One of the major improvements proposed in this study is to investigate the methods of synthesizing aragonite crystalline particles using a continuous mineral carbonation reactor system and optimizing the operating parameters. An experimental design was established to identify all the main effects to maximize aragonite production. The three main effects investigated are the effect of feedstock or reactant concentration, the effect of reaction temperature, and the effect of reaction time towards aragonite yield in the final products synthesized. An optimized operating parameter for maximum aragonite yield at 95% purity was proposed at the reaction temperature T of 90 °C, reaction time t of 10 min, and feedstock ratio Mg-to-Ca of 0.4. Subsequently, the continuous reactor system was designed, operated, and tested for at least 50 h operation, where the lime CaO(s) feed was successfully converted into aragonite products with purity between 75 and 81%. The properties and quality of the aragonite produced were analytically characterized from the following laboratory methods which include the thermalgravimetric analysis, TGA; X-Ray Diffraction, XRD; scanning electron microscopy, SEM; and induction coupled plasma, ICP. TGA mass balance after decomposition suggests that 44% of the mass balance represents the weight of CO₂ sequestered in the aragonite crystalline carbonates. Hence, the aragonite crystalline carbonates can be labeled as a green product which sequesters 0.44 kg of CO₂ per 1 kg of precipitated aragonite products synthesized. Interestingly, SEM microscopy characterization results revealed that the aragonite precipitate has a physical morphology of needle-like shape with a good aspect ratio (length/diameter) AR of between 8.67 micron and 11.35 micron. The properties were found to be suitable for paper making fillers, medical, personal care, and food additive applications. Full article

The synthesis of precious metal nanoparticles (PM-NPs) is an important field of research that has expanded significantly in recent decades due to their numerous applications. Therefore, research has been directed toward developing green methods for the synthesis of such nanoparticles that are simple, safe, eco-friendly, efficient, and sustainable. In this context, the use of marine algae biomass for the green synthesis of PM-NPs can be a viable large-scale alternative, as algae are easy to cultivate, have a rapid growth rate, and are widely distributed across many regions of the globe. The reduction of precious metal ions takes place at the surface of algae biomass particles, and the characteristics of the resulting precious metal nanoparticles depend on the experimental conditions (pH, amount of algae biomass, contact time, etc.), as well as on the type of algae biomass and the speciation form of the metal ions in the solution. All these factors significantly influence the properties of precious metal nanoparticles, and their understanding allows the development of synthesis strategies that can be applied on a large scale. The aim of this review is to provide a comprehensive overview of the way in which PM-NPs can be synthesized using algae biomass. The importance of experimental conditions (such as pH, contact time, amount of biomass, type of algal biomass, temperature, etc.) on the synthesis efficiency, as well as the elementary steps involved in the synthesis, is also discussed in this study. Particular attention has been paid to the analytical methods used for characterizing PM-NPs, as they provide crucial data regarding their structure and composition. These aspects are essential for identifying the practical applications of PM-NPs. Full article

Reliable tools for cultivar discrimination and ripening stage evaluation are critical to optimize harvest timing and support milling process focused on olive oil quality. This research examines the spectral properties of olive drupes throughout different maturation stages, ranging from green to full purple-black pigmentation, across 29 distinct cultivars. High-resolution spectrometric analysis was conducted within the 380–1080 nm wavelength range. Multiple analytical approaches were employed to optimize wavelength selection from hyperspectral reflectance data to obtain discriminating tools for olive classification. A Biologically Informed Wavelength Extraction method (BIWE) was developed, focusing on cultivar and ripening stages identification, and pivoted on biologically informed single wavelengths and Vegetation Indices (VIs) selection. The methodology integrated multi-scale spectral analysis with biochemically weighted scoring and a multi-criteria evaluation framework, employing a two-iteration refinement process to identify optimal spectral features with high discriminatory power and biological relevance. Analysis revealed spectral variations associated with maturation. A characteristic reflectance peak at approximately 550 nm observed during early ripening stages underwent a notable shift, developing into distinct spectral behavior within the 700–780 nm range in intermediate and advanced ripening stages and reaching a plateau for all the samples between 800 and 950 nm. The BIWE method achieved exceptional efficiency in olive classification, utilizing only 25 single wavelengths compared to 114 required by Principal Component Analysis (PCA) and 131 by Recursive Feature Elimination (RFE), representing 4.6-fold and 5.2-fold reductions, respectively. Despite this reduction, BIWE’s overall accuracy (0.5634) remained competitive compared to RFE (−10%) and PCA (−8%) alternative approaches requiring larger wavelengths dataset acquisition. The integration of biochemically relevant VIs enhanced accuracy across all methodologies, with BIWE demonstrating notable improvement (+19.2%). BIWE demonstrated effective olive identification capacity with a reduction in required wavelengths and VIs dataset, affecting the technological needs (spectrometer offset and real-time classification applications) for a tool oriented to olive cultivars and ripening stage discrimination. Full article

Theophylline represents a significant public health challenge due to its dual acute and chronic toxicity resulting from therapeutic, environmental, and dietary exposures. Effective monitoring across the bio-environmental–food triad requires analytical methods that are highly sensitive, universally applicable, and capable of overcoming complex matrix interferences. This study introduces a flat membrane-based liquid-phase microextraction (LPME) technique combined with LC–MS/MS for the determination of theophylline in diverse matrices. The method eliminates the need for specialized adsorbents or equipment, offering a simple and cost-effective solution for high-throughput sample clean-up. Under optimized conditions, the method demonstrated exceptional sensitivity (LOD: 0.2 ng mL⁻¹) and a wide linear range (0.01–10 μg mL⁻¹). It was successfully applied to plasma, urine, hospital sewage, and green tea, providing accurate (recoveries of 86.7–111.3%) and reproducible (RSD < 10%) results across all matrices. This unified and robust approach effectively addresses matrix interferences and provides a reliable tool for the monitoring and risk assessment of theophylline across multiple domains. Full article

Adhering to the principles of green analytical chemistry (GAC) is crucial for advancing sample pretreatment. In this work, we developed a green in-tube solid-phase microextraction (IT-SPME) material utilizing non-toxic cyclodextrin and zwitterionic polymers as co-functioning monomers. The hybrid monolithic material was synthesized within 38 min via an efficient epoxy ring-opening reaction and free radical polymerization. Comprehensive characterization confirmed a rigid framework with strong anti-swelling properties, good permeability, and high enrichment efficiency on the polymers. When coupled with HPLC-UV, the optimized IT-SPME method enabled highly sensitive detection of polypeptides (vancomycin and teicoplanin) in aqueous matrices, achieving detection limits as low as 15.0–20.0 μg L⁻¹, a wide linear range (60–800 μg L⁻¹, R² > 0.99), and good precision (RSDs = 5.9–8.2%). The prepared material demonstrated remarkable performance in real complex water samples, achieving recovery rates of up to 95.4%. Density functional theory (DFT) calculations indicated that the adsorption mechanism primarily involves hydrogen bonding and electrostatic interactions. This study presents an effective approach for the development of green chemical synthesis of extraction materials and offers a sustainable platform for monitoring trace contaminants in environmental waters. Full article

Food irradiation is a clean, safe and non-thermal technology applied to destroy pathogenic microorganisms, i.e., Salmonella spp., in hen eggs. Currently, in Europe only the egg white can be irradiated up to 3 kGy, so different control methods are crucial for official inspections to identify illicit treatments. In this work, an analytical method was proposed to determine the radiolytic markers, namely 2–dodecylcyclobutanone (2–DCB) and 2–tetradecylcyclobutanone (2–TCB) in hen egg samples. This method is based on headspace solid phase micro-extraction coupled with gas chromatography/mass spectrometry (HS–SPME/GC–MS). The eggs were treated by an X-ray irradiator at dose levels of 0.5, 1.0 and 3.0 kGy. The preliminary validation showed good selectivity, without matrix interferences in non-irradiated samples. Spiked samples showed linear responses in the range 2.5–25.0 µg kg⁻¹, where 2.5 µg kg⁻¹ was the limit of detection for both analytes. Irradiated samples showed a dose-dependent increase in signal intensity and a constant 2–DCB/2–TCB ratio. The minimum dose level detected was 0.5 kGy for all samples, and the 2–DCB and 2–TCB signals remained stable over one month after irradiation. Not least, white analytical chemistry was used to evaluate the HS–SPME/GC–MS method validation effectiveness, greenness power and economic efficiency, compared to the EN 1785:2003 standard method. The results of this study prove that the HS–SPME/GC–MS method is a reliable green alternative to the official method, which is suitable in food safety control programs. Full article

Conventional methods for testing steroids and hormones (SHs) in environmental samples are exhaustive, complex, and score poorly in sustainability matrices. Therefore, this study evaluates the automated sample preparation approach using the modular Biomek i7 Workstation for the analysis of 27 SHs in wastewater. Method development involved optimizing Ultra Performance Liquid Chromatography–Tandem Mass Spectrometry (UPLC-MS/MS) parameters, preparing wastewater matrix blank, and assessing extraction efficiency using three solid phase extraction (SPE) cartridges. Extraction efficiency trials showed suitability in the order of Hydrophilic–Lipophilic Balance (HLB) > Mixed-Mode Cation Exchange (MCX) > Mixed-Mode Anion Exchange (MAX). The method demonstrated specificity for all targeted SHs, with Cholesterol showing a maximum interfering peak of 17.71% of the quantification limit (LOQ). The method met matrix effect tolerance of ±20% for 26 SHs, while Epi Coprostanol (34.92%) showed signal enhancement >20%. The 8-point calibration curve plotted using automated extraction demonstrated acceptable linearity across the tested range. Spiked studies at low (LQC), middle (MQC), and higher (HQC) quality control (QC) levels (n = 6, repeated on three separate occasions) demonstrated % RSD values within 20% and recoveries ranging from 71.54% to 115.00%. The method met validation criteria, showing reliability in Intra-Laboratory Comparison (ILC) and Blind Testing (BT). The method outperformed the conventional approach in greenness assessment (Complex Modified Green Analytical Procedure Index) and practicality evaluation (Blue Applicability Grade Index), offering an effective and sustainable protocol for environmental testing laboratories. Full article

Conventional methods for detecting pharmaceutical and personal care products (PPCPs) in environmental samples are complex, resource-intensive, and not sustainable. Therefore, this study aimed to evaluate an automated sample preparation approach using the Biomek i7 Workstation to analyze 69 PPCPs in wastewater, with the objective to improve monitoring of public health and environmental protection. The method underwent extensive development, including optimization of UPLC-MS/MS parameters, preparation of wastewater matrix blank sample and assessment of extraction efficiency using three types of SPE cartridges. Extraction efficiency trials revealed that the order of suitability for SPE cartridges is Mixed-Mode Anion Exchange (MAX) > Mixed-Mode Cation Exchange (MCX) > Hydrophilic–Lipophilic Balance (HLB). The method demonstrated specificity for all targeted PPCPs, with the max interfering peak for 1, 7 Dimethylxanthine reaching 14.79% of the response at the target limit of quantification (LOQ). The method met ±20% matrix effect tolerance for 63 PPCPs, while 6 PPCPs showed signal enhancement. The 8-point procedural calibration curve prepared using automated robotic extraction has demonstrated linearity across the tested range. A spiking study at low (LQC), medium (MQC), and high (HQC) quality control levels (n = 6), repeated on three separate occasions, showed % RSD values within 20% and % recovery between 80 and 120%. The method met validation requirements, showed reliability in Intra-Laboratory Comparison, Blind Testing (BT) and received high ratings for greenness (Green Analytical Procedure Index, Analytical GREEnness) and practicality (Blue Applicability Grade Index). Full article

To facilitate the sustainable recycling of retired wind turbine blades (RWTBs) and promote the green development of the wind energy sector in China, this study investigates the reuse of crushed RWTBs as composite fiber additives in asphalt mixtures. A systematic optimization of the incorporation process was conducted, and the effects of RWTB fibers on pavement performance were comprehensively evaluated. Using the entropy weight method, the optimal fiber content and particle size were identified as 0.15 wt% and 0.3–1.18 mm, respectively. The experimental results demonstrated that, under optimal conditions, the dynamic stability, low-temperature flexural tensile strain, Marshall stability after water immersion, and freeze-thaw splitting strength of the base asphalt mixture increased by 27.1%, 23.8%, 9.9%, and 8.1%, respectively. Microstructural analyses using SEM and EDS revealed that the reinforcing mechanism of RWTB fibers involves adsorption, bridging, and network formation, which collectively enhance the toughness and elasticity of the asphalt matrix. In addition, a comparative evaluation was performed using the Analytic Hierarchy Process (AHP), incorporating both performance and cost considerations. The comprehensive performance ranking of fiber-modified asphalt mixtures was consistent for both base and SBS-modified asphalt: BF AC-13 > RWTB AC-13 > GF AC-13 > PF AC-13 > unmodified AC-13. Overall, this study confirms the feasibility of high-value reuse of RWTB waste in road engineering and provides practical insights for advancing resource recycling and promoting sustainability within the wind power industry. Full article

Background: Urban loneliness is rising worldwide and is a recognised public-health threat. Nature-Based Social Prescriptions (NBSPs), guided group activities in natural settings, are being piloted in six cities through the EU project RECETAS. However, in new contexts such as Marseille, its implementation is constrained by professionals’ limited knowledge of the concept. Objectives: (i) Exploring how professionals in Marseille (France) conceptualise NBSPs; (ii) Identifying perceived facilitators and barriers to implementing NBSPs among residents facing social isolation and loneliness. Methods: Twelve semi-structured interviews were conducted with health, social-care, and urban–environment professionals selected via network mapping and snowball sampling. Verbatim transcripts underwent inductive thematic analysis informed by Social Representation Theory, with double coding to enhance reliability. Results: Five analytic themes emerged: (1) a holistic health paradigm linking nature, community, and well-being; (2) stark ecological inequities with limited green-space access in deprived districts; (3) work challenges due to the urgent needs of individuals facing significant socio-economic challenges in demanding contexts; (4) a key tension between a perceived top-down process and a preference for participatory approaches; (5) drivers and obstacles: strong professional endorsement of NBSPs meets significant systemic and institutional constraints. Conclusions: Professionals endorse NBSPs as a promising approach against loneliness, provided programmes tackle structural inequities and adopt participatory governance. Results inform the Marseille RECETAS pilot and contribute to global discussions on environmentally anchored health promotion. Full article

As Shared Autonomous Vehicles (SAVs) emerge as a transformative force in urban mobility, integrating them into dense, historic urban environments presents distinct spatial and planning challenges—such as narrow street patterns, irregular road networks, and the need to protect cultural heritage. This study investigates the spatial adaptability of SAVs in Suzhou old town, a representative example of East Asian heritage cities. To assess spatial readiness, a hybrid weighting approach combining the Analytic Hierarchy Process (AHP) and the Entropy Weight Method (EWM) is used to evaluate 22 spatial indicators across livability, mobility, and spatial quality. These weighted indicators are mapped using a spatial density analysis based on Point of Interest (POI) data, revealing urban service distribution patterns and spatial mismatches. Results show that “Accessibility to Transportation Hubs” receives the highest composite weight, emphasizing the priority of linking SAVs with existing subway and bus networks. Environmental comfort factors—such as air quality, noise reduction, and access to green and recreational spaces—also rank highly, reflecting a growing emphasis on urban livability. Drawing on these findings, this study proposes four strategic directions for SAV integration that focus on network flexibility, public service redistribution, ecological enhancement, and cultural preservation. The proposed framework provides a transferable planning reference for historic urban areas transitioning toward intelligent, human-centered mobility systems. Full article

The prefabricated reinforced concrete columns–steel girder (RCS) hybrid frame structure using column–column connections is a kind of green and environmentally friendly building structure; its seismic performance is investigated. The seismic susceptibility and key influencing factors are systematically evaluated through the establishment of an analytical model and incremental dynamic analysis (IDA) method. A typical three-span, six-story prefabricated RCS hybrid frame structure is designed and numerically modeled with good agreement with the test data. Sa(T1,5%) and PGA double ground motion intensity parameters are selected for IDA analysis. A comparison between the quantile curve method and the conditional logarithmic standard deviation method reveals that using Sa(T1, 5%) as the intensity measure (IM) provides greater reliability for analyzing the vulnerability of the prefabricated RCS hybrid frame structure. The seismic probability demand model of the structure is fitted with Sa(T1,5%) as a parameter and the seismic fragility curves of the structure are plotted; this shows that the slope of the seismic fragility curves becomes smaller after the structure enters the elastic–plastic state, and exhibits good seismic performance. By studying the effects of concrete strength, longitudinal reinforcement strength, and the axial compression ratio on the seismic fragility, it can be seen that with the increase in concrete strength and longitudinal reinforcement strength, and the decrease in axial compression ratio, the overall ductility of the structure increases, the resistance to lateral deformation of the RCS hybrid frame structure is enhanced, and the seismic performance of the prefabricated structure is improved. Full article

In the context of the “dual-carbon” goal to promote the green and low-carbon transformation of the economy, the mechanism of environmental regulation as a core policy tool for carbon emission reduction remains theoretically controversial. Based on this, this paper uses panel data from 30 provinces in China from 2015 to 2022 and adopts a two-way fixed-effects analysis method to examine the direction and intensity of the impact of environmental regulations on carbon emissions, introducing industrial intelligence and green technological innovation as mediating variables. Research indicates that (1) for every 1-unit increase in the intensity of environmental regulation, carbon emissions are reduced by about 0.9866 units on average, and its carbon emission reduction effect is more significant in the eastern region, where the proportion of secondary industry is medium and high, as well as in non-technology-intensive regions. (2) Industrial intelligence and green technological innovation play a partial mediating role between environmental regulations and carbon reduction. (3) After categorizing green technology innovations, it is found that environmental regulations do not significantly incentivize substantive green technology innovations, but they can contribute to carbon emission reduction by promoting the development of strategic green technology innovations. (4) The analysis of spatial effects shows that carbon emissions in China’s provinces are characterized by significant spatial agglomeration. Enforcement of environmental regulations also exerts a suppressive effect on carbon emissions in adjacent provinces, and its carbon emission reduction effect is characterized by “total effect > indirect effect > direct effect”. Compared with existing studies, this paper elucidates the transmission mechanism whereby environmental regulation achieves carbon emission reductions through industrial intelligence and green technological innovation, thereby contributing a novel analytical framework for examining regulatory impacts on carbon emissions while furnishing actionable policy implications for facilitating socioeconomic greening and low-carbon transitions. Full article

The growing demand for sustainable biorefinery approaches calls for efficient, environmentally benign strategies to valorize agricultural residues and ensure their complete utilization. This study explores the combination of deep eutectic solvents (DESs) and microwave heating technology as a greener process for the selective fractionation of agri-food waste residues in a zero-waste perspective. Within this framework, five representative biomasses were thoroughly investigated, namely brewer’s spent grain, raw and parboiled rice husks, rapeseed cakes, and hemp hurds. DES formulation was selected for its ability to solubilize and separate lignocellulosic components, enabling the recovery of a polysaccharide-rich fraction, lignin, and bioactive compounds. DES extraction was performed using both microwave heating and conventional batch heating, enabling a direct comparison of the two methods, the optimization of a more sustainable fractionation process, and the maximization of yields while preserving the functional integrity of the recovered fractions. A comprehensive characterization of the separated fractions was carried out, revealing that the two fractionation methods do not yield significant differences in the composition of the primary components. Moreover, a ¹³C CP-MAS NMR analysis of the recovered lignins demonstrates how this analytical technique is a real fingerprint for the biomass source. The results demonstrate the great potential of microwave DES-mediated fractionation as a mild, tunable, and sustainable alternative to conventional methods, aligning with green chemistry principles and opening new approaches for the full valorization of waste byproducts Full article

In this paper, we present a set of experimental data (SESD) from Capsicum annuum with two different pigmentations, obtained using a self-made computed tomography spectrometer (CTIS), which adapt to the optical model of radiative transfer. An optical model is based on the directional-hemispheric reflectance and transmittance of a turbid medium with plane-parallel layers. To estimate the fruit’s primary pigments (Chlorophyll, Carotenoids, Capsanthin, and Capsorubin), we use the optical model combined with a numerical search and optimization method based on a robust and efficient multi-objective genetic algorithm (GA), allowing us to find the closest solution to the global minimum; and the inverse problem is solved by obtaining the best fit of the analytical function defined in the SESD optical model. Values of pigment concentrations retrieved with the proposed GA show a total difference of 2.51% for green pepper and 5.60% for red pepper compared with those reported in the literature. Full article