Search Results (231)

LIFE REVIVE aims to restore ecological status and ecosystem services in the Lima and Vouga river basins (NW Iberian Peninsula), where hydromorphological alteration and hydropower-driven flow regulation are major causes of water bodies failing to reach Good Ecological Status under the EU WFD. The project targets key pressures such as longitudinal fragmentation by weirs and dams, artificial flow regimes, degradation of spawning substrates, and the spread of invasive aquatic plants, which strongly affect fish communities, including sea lamprey, salmonids, and other diadromous species. Technically, the project combines barrier removal or eco-adaptation, nature-like fish passes, and spawning-habitat renaturalisation with optimized environmental flow regimes (EFR) downstream of important hydropower systems, explicitly accounting for present and future hydroclimatic scenarios. Multi-scale ecohydrological modelling (species distribution models, habitat suitability models, GLM/GAM approaches) will quantify fish–flow–habitat relationships and support the definition of operational EFR guidelines that balance ecological requirements with hydropower and agricultural constraints through joint work with the main Portuguese hydropower operator, EDP. Impact evaluation is structured around a rigorous BACI monitoring design in intervention and control tributaries, using standard WFD biological indices for fish and aquatic/riparian vegetation, hydromorphological indices (HQA, HMS, RHS), and project-specific Key Performance Indicators for water quality, biodiversity, and habitat. Expected outcomes include the restoration of at least 51 km of rivers towards free-flowing conditions, reduced hydromorphological pressure in more than 20 km of heavily modified river stretches, and measurable increases in the distribution and abundance of fish species and native vegetation. A strong communication and capacity-building programme underpins public engagement, while a decision matrix for barrier prioritization, technical workshops, and pilot replications in additional basins (e.g., Alva, Mouro, Deva, and Tea in Galicia) are designed to maximize transferability, policy uptake, and long-term sustainability of the solutions beyond the project lifetime. Full article

Triethylamine (TEA), a widely used volatile organic compound (VOC), poses severe threats to environmental safety and human health upon accidental leakage, making the development of high-performance TEA detection techniques urgently needed. Herein, we report a Sn-based metal–organic framework (Sn-MOF) constructed from 4,5-dichloroimidazole ligands synthesized via a solvothermal approach. The resulting MOF-derived SnO₂ materials were obtained by calcination at 400–600 °C, yielding SnO₂ with tunable specific surface area and surface defect-site density. Structural and surface characterizations revealed that the materials consist of primary nanoparticles in the range of 10–50 nm, forming aggregated particles of 1–2 µm. The gas sensing performance toward TEA was systematically evaluated. The SnO₂-400 °C sensor exhibited the highest response (S = 85.0) to 100 ppm TEA at 190 °C, with a low detection limit of 1 ppm, superior selectivity, good repeatability, and excellent long-term stability. The observed performance variation was attributed to the combined effects of specific surface area, abundant defect-associated surface sites, and suitable mesoporous structure. This work not only provides a high-performance TEA sensor for industrial and food safety monitoring but also offers a rational strategy for designing MOF-derived metal oxide gas sensors with tailored microstructures and surface defect chemistry. Full article

Cement clinker production is a thermal- and emissions-intensive process requiring high-temperature heat for drying, calcination, and sintering. This review provides a process-based assessment of refuse-derived fuel (RDF), solid recovered fuel (SRF), tire-derived fuel (TDF), and biomass as partial substitutes for coal and petcoke in modern dry-process cement kilns. The study synthesized the evidence from plant-scale trials, pilot and laboratory experiments, process modeling, computational fluid dynamics, emissions studies, life-cycle assessment (LCA), techno-economic analysis (TEA), and regional case studies to evaluate alternative fuels across fuel properties, kiln-zone suitability, process stability, clinker quality, emissions performance, and environmental outcomes. The review shows that stable co-processing generally requires fuels with net calorific values above 14 MJ kg⁻¹ and moisture contents below 15%, although TDF can provide 26–33 MJ kg⁻¹ and sustain high-energy kiln duty when sulfur, zinc, and steel residues are controlled. RDF, SRF, and biomass require pre-processing, homogenization, calibrated dosing, and continuous fuel-quality monitoring to limit incomplete burnout, deposit formation, volatile circulation, and clinker-quality variation. LCA studies show that 20% RDF thermal substitution can reduce global warming potential by about 3.3–4.2%, increasing to approximately 6.7% when avoided landfill methane credits are included. Modern abatement systems can maintain particulate matter at about 10–30 mg Nm⁻³ and PCDD/F below 0.1 ng TEQ Nm⁻³ under stable operation. The review concludes that alternative fuels are quality-dependent co-processing options whose mitigation role is complementary to clinker-factor reduction, energy-efficiency improvement, low-clinker binders, electrified heating, oxy-fuel calcination, and carbon capture. Full article

To investigate how spreading conditions affect green tea taste and aroma and to develop a generalizable prediction model from small data for process optimization, this study integrated SEM, non-targeted dual-omics, and TabPFN to systematically analyze Echa No. 10 spreading. A central composite design was used. Dehydration-induced mechanical stress altered cell membrane permeability, driving non-volatile taste compound transformation and volatile aroma release. Two chemical-sensory proxies, relative polyphenol-to-amino acid ratio (R-PAR) and floral intensity index (FII), were established using ultra-high performance liquid chromatography–high-resolution mass spectrometry (UHPLC-HRMS) and headspace solid-phase microextraction–gas chromatography–mass spectrometry (HS-SPME-GC-MS). A prediction model was built with these indicators and TabPFN. Multi-objective optimization yielded optimum conditions: initial moisture 76.8%, temperature 26.2 °C, relative humidity 61.5%, air speed 0.85 m/s, achieving R-PAR 0.465 and FII 125.70. Compared with response surface methodology (RSM), partial least squares regression (PLSR), and support vector regression (SVR), TabPFN showed prediction R² of 0.81 and 0.77, showing favorable applicability and predictive capability on small-sample data. This study validates TabPFN’s suitability for small-sample tea processing modeling, quantifies the mapping between spreading and key taste/aroma metabolism, and provides a methodological foundation for digital precision and intelligent optimization in green tea production. Full article

Rapid and efficient elemental characterization of lignocellulosic biomass, such as grapevine cane residues, is essential for its effective utilization in energy and material applications; however, conventional analytical methods typically require extensive sample preparation and are therefore not suitable for rapid screening purposes. In this study, laser-induced breakdown spectroscopy (LIBS) based on TEA CO₂ laser ablation is applied as a direct and minimally destructive approach for the analysis of grapevine cane biomass. Emission spectra recorded in the 190–780 nm range enabled qualitative identification of the elements present in the biomass, supporting the applicability of LIBS for multi-element analysis of complex solid matrices. Quantitative determination of Mg, Ca, K, and Na was achieved using an external calibration approach with solid-spiked standards, yielding good linearity (R² = 0.976–0.990), with concentrations in good agreement with reference ICP–OES measurements. Plasma diagnostics indicated a temperature of approximately 10,500 K and an electron number density on the order of 10¹⁶ cm⁻³, supporting the assumption of local thermodynamic equilibrium (LTE) conditions. The results demonstrate that LIBS provides a rapid and practical tool for direct elemental screening of vine shoot biomass, with potential application in the assessment of agricultural residues for carbon-based material production and related valorization pathways. Full article

Teas processed from specialty-colored tea leaves possess distinctive quality profiles shaped by their volatile and non-volatile compounds, which serve as critical metrics for evaluating tea cultivars. In this study, we comprehensively characterized the quality attributes of flat green teas produced from three tea cultivars—green-leaved ‘FDDB’, yellow-leaved ‘ZH2’, and purple-leaved ‘ZJ’—using an integrated analytical approach including sensory evaluation, widely targeted metabolomics, GC-E-nose, and HS-SPME-GC-MS. Sensory evaluation revealed distinct sensory characteristics among teas processed from the three cultivars with different leaf colors. GC-E-nose analysis further confirmed that the aroma profiles of these tea samples could be clearly distinguished based on leaf color. Metabolomic analysis identified a total of 2050 non-volatile compounds, among which 18 amino acids, 5 phenolic acids, and 4 flavonoids were pinpointed as key contributors to the unique taste profiles of infusions from ZH2 and ZJ teas. Additionally, a total of 1100 volatile compounds were detected, with 94, 75, and 90 key aroma-active compounds identified in FDDB, ZH2, and ZJ teas, respectively. Collectively, in this study, systematic analysis revealed significant differences in both volatile and non-volatile chemical compositions across the three tea cultivars. These findings provide a scientific foundation for understanding the processing suitability and quality formation mechanisms of tea cultivars with distinct leaf colors. Full article

Chunmee tea quality is critical to its grading, and accurate identification is essential for quality evaluation and market valuation. However, traditional machine learning relies on manual feature extraction and causes spectral information loss, while conventional one-dimensional convolutional neural networks (1D-CNNs) are restricted by fixed kernels and narrow receptive fields, making multi-scale feature capture difficult. In this study, an improved DeepSpectra model integrated with the Inception module and residual connections was proposed for end-to-end automatic grading of Chunmee tea. A total of 360 samples across six grades (60 samples per grade) were collected using an Antaris II near-infrared spectrometer and preprocessed by multiplicative scatter correction (MSC). The proposed model was compared with other models. Results showed that under a 7:1:2 train–validation–test split, the proposed DeepSpectra achieved an average test accuracy of 96.39 ± 1.63% across ten random sample divisions, significantly outperforming the other models (p < 0.05). The model also exhibited excellent stability in five-fold cross-validation and superior generalization in small-sample scenarios, and a lightweight structure with low inference latency of 2.2 ms, which is suitable for real-time industrial applications. This work provides a reliable, efficient, and end-to-end method for grading Chunmee tea and offers a promising strategy for intelligent and rapid quality control of green tea. Full article

The picking of tea leaves in tea gardens requires multiple batches in the short and valuable tea harvest period. To realize timely and efficient tea plucking, it is feasible to use unmanned aerial vehicles (UAV) for tea shoot detection in large tea gardens. For the typical small targets of tea buds in unmanned aerial vehicle (UAV) aerial images, it is necessary to design an efficient tea buds detection model. In order to improve the accuracy and the speed of the tea buds detection in the UAV images, we designed the SH-CoordMapping hash space mapping algorithm to accelerate the remerging of the detection results into the original image. The C2PSA-BI module and the CARAFE upsampling module are applied to improve detail preservation during feature fusion. A lightweight detection head is further used to reduce redundant computation in the detection stage. By comparing with the traditional detection methods, it can be proved that the SWO sections are necessary for UAV-scale tea shoots detection. Based on the accuracy and the number of model parameters, the YOLO11n model with slice size as 640 and overlap rate as 0.1 performs the best. The TSDet-UAV was deployed on the NVIDIA Jetson Orin NX chip to construct an inspection system capable of real-time acquisition and detection. The experimental results demonstrate that the proposed TSDet-UAV achieves excellent performance, recording an mAP₅₀ of 52.9% on the constructed UAV-TS dataset while maintaining high efficiency. With a parameter size of 2.4 M and a total processing time of 1.32 s per high-resolution image under TensorRT FP16, the processing speed is highly suitable for real-time edge deployment on agricultural UAV platforms. The UAV image-based tea garden shoot inspection platform proposed in this paper can effectively confirm the growth status of tea shoots, assisting farm management in formulating precise picking plans. Full article

As a new type of tea, Lonicera tender bud tea currently lacks clear scientific standards for variety selection and harvest time determination, and relevant research on its components is insufficient. This study focused on ‘Beihua No.1’ and ‘Red Honeysuckle’ as research objects and systematically analyzed their quality-related components using GC-IMS and electronic sensory technology. The results showed that: the basic nutritional components of ‘Beihua No.1’ were highest in August, and main pharmacological components peaked in April, with a high content of loganin; the components of ‘Red Honeysuckle’ were optimal in June, with a high concentration of swertiamarin. GC-IMS analysis revealed that ‘Beihua No.1’ contained 71 volatile substances, and ‘Red Honeysuckle’ contained 79 volatile substances, both mainly composed of esters and heterocyclic compounds. Through VIP analysis (VIP > 1), ‘Beihua No.1’ had 18 key differential components, including Methyl non-2-ynoate, 4-methylbenzaldehyde, cyclopentanone, etc.; ‘Red Honeysuckle’ had 28 key differential components, including 2,3,5,6-tetramethylpyrazine, 2-isopropyl-5-methylcyclohexanone, (E,E)-2,4-heptadienal, etc. Cluster analysis confirmed that ‘Beihua No.1’ is suitable for fresh-tasting tea, while ‘Red Honeysuckle’ is suitable for mellow-tasting tea. This study provides scientific support for the high-value development and standardized production of both. Full article

The popularity of herbal remedies is on the rise, but this often comes at the expense of general knowledge about non-native species. The frequency and versatility of the use of medicinal plants does not depend on their origin, while the use of species with proven efficacy is much more intensive. The most abundant plant families, according used taxa and use records, are Asteraceae, Rosaceae and Lamiaceae. The greatest consensus is on the choice of taxa suitable for the treatment of bloating/flatulence and diarrhea, most commonly treated with Carum carvi L. fruit tea and dried or fresh berries of Vaccinium myrtillus L., respectively. The most popular species for treatment of digestive disorders are Artemisia absinthium L. and Matricaria chamomilla L. The use of different taxa for the treatment of digestive disorders in Lithuania varies considerably for a number of reasons, one of which is the uneven distribution of medicinal plant species in the study areas. Full article

Achieving tunable morphologies of Fe₃O₄ using a single iron source remains challenging, mainly due to the oxidation of Fe²⁺ and the difficulty of regulating anisotropic crystal growth. In this study, Fe₃O₄ was synthesized via a one-step hydrothermal method using FeSO₄·7H₂O as a single iron source in a TEA–NaOAC synergistic system. The effects of hydrothermal temperature, additive ratio, and dosage were systematically investigated. Time-dependent and TEA dosage-dependent experiments were also designed to elucidate the morphological evolution mechanism. The results show that pure-phase Fe₃O₄ can be obtained with TEA alone, as TEA controls the release rate of Fe²⁺ and inhibits its oxidation. However, the synergistic addition of NaOAC provides a mild alkaline environment that not only maintains phase purity but also further promotes anisotropic crystal growth and enables a broader morphological tunability. By tuning the reaction conditions, a systematic morphological evolution from flower-like to cubic, regular octahedral, and polyhedral structures was achieved. Time-dependent experiments reveal a complete dissolution–recrystallization pathway from flower-like to cubic structures. TEM and SAED confirm that the polyhedral particles are micrometer-sized single crystals. Under optimized conditions (160 °C, TEA 3 mL, NaOAC 26 mmol), the polyhedral Fe₃O₄ exhibits a saturation magnetization of 91.4 emu/g, approaching the bulk theoretical value (92 emu/g), and a coercivity of approximately 100 Oe. This study provides new experimental evidence for morphology regulation of Fe₃O₄ using a single iron source, achieving high saturation magnetization close to the bulk theoretical value and moderate coercivity suitable for non-biomedical applications. Full article

Despite its rich bioactive composition, orange peel dust (OPD), a fine industrial by-product generated during citrus processing in the filter tea industry, has not received much attention as a valuable matrix. Using antioxidant activity (2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and reducing power (RP)), α-amylase inhibitory activity, antimicrobial potential, and sugar composition as function-oriented indicators, this study aimed to compare four green extraction technologies: subcritical water extraction (SWE), pressurized ethanol extraction (PEE), ultrasound-assisted extraction (UAE), and sequential supercritical CO₂–UAE (Sc-CO₂–UAE) applied to OPD derived from Citrus sinensis L. Among thermally driven techniques, PEE at 220 °C had the highest radical-scavenging activity, while UAE showed the broadest antifungal activity against Fusarium spp. and Alternaria alternata, along with selective antibacterial activity against Bacillus cereus. Sequential Sc-CO₂ pretreatment at 300 bar followed by UAE resulted in the highest α-amylase inhibitory activity. Sugar analysis indicated that thermal conditions enhanced carbohydrate hydrolysis, while UAE and Sc-CO₂-UAE maintained structural sugars under mild conditions. All green extraction approaches outperformed conventional maceration. These findings validate OPD as a valuable industrial by-product suitable for sustainable valorization, supporting circular economy concepts in the citrus processing sector. Full article

The increasing popularity of fermented beverages, such as kombucha, has prompted the search of alternative ingredients with distinct functional and sensory properties. Orange (Citrus sinensis L. Osbeck) peel, an abundant by-product of the citrus industry, represents a valuable natural source of flavanones associated with multiple health benefits, offering a suitable substrate for fermentation. In this context, the present study proposes the valorisation of this by-product through the development of a new fermented beverage analogous to kombucha, rich in bioactive flavanones. During the fermentation process, variations were observed in physicochemical quality parameters (pH (4.86–2.91), titratable acidity (maximum 0.45% as acetic acid), and total soluble solids (TSS) (6.90–7.05 °Brix), as well as in the fermentation metabolites and substrates: sucrose (73.99–45.75 g/L), fructose (0.98–6.87 g/L), glucose (1.60–1.35 g/L), ethanol (0.06–0.24 g/L), and acetic acid (0.45–3.00 g/L). On the other hand, the initial total flavanone content (11.85 mg/100 mL), of which 70% corresponded to hesperidin, decreased during fermentation but then remained stable, reaching a final concentration of 5.72 mg/100 mL. Overall, these results highlight the potential of orange peel by-products for the development of innovative fermented beverages with a high content of bioactive flavanones, which are distinct from conventional tea-based kombucha. Moreover, this strategy represents a potential approach for this citrus waste valorisation, contributing to improved resource efficiency and supporting the transition towards a circular economy. Full article

The biochemical diversity among tea plant (Camellia sinensis) cultivars serves as the core material basis associated with tea quality and is of great significance for the innovation of tea germplasm resources and the genetic improvement of tea varieties. Here, we systematically analyzed 16 biochemical components, 7 mineral elements, and water-soluble fluoride (WSF) in 65 tea cultivars using multivariate analysis. These cultivars were grouped into high-component, high-epigallocatechin (EGC), low-component, and balanced-quality clusters. Significant variation was observed in quality-related parameters, including tea polyphenols, catechins, and amino acids and related quality indices. Mineral elements were significantly correlated with quality components, with potassium and boron showing significant correlation with the accumulation of these components. WSF content exhibited a pronounced cultivar-dependent variation, with more than 72% of cultivars containing less than 100 mg·kg⁻¹. The balanced-quality cluster exhibited broad processing adaptability, making it suitable for producing various tea types. The high-EGC cluster is ideal for developing specialty functional teas. The high-component cluster offers core parental material for breeding cultivars high in tea polyphenols and epigallocatechin gallate. This study provides a scientific basis for the screening and utilization of tea germplasm resources and the development of new, high-quality, and safe tea varieties. Full article

The herbal tea industry has experienced substantial growth, particularly regarding green tea (Camellia sinensis). In the manufacturing of filter tea, fine herbal dust is generated as a residual by-product during grinding and sieving and is typically discarded as waste. This study aims to explore the application of ultrasound-assisted extraction (UAE) for secondary valorisation of green tea herbal dust by investigating the effects of various parameters on extraction efficiency. Antiradical activity of UAE extracts was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, and the total phenolic content (TPC) was measured using Folin–Ciocalteu’s assay. Furthermore, selected phenolics were quantified by HPLC and qualitatively characterised by liquid chromatography coupled with electrospray ionisation and quadrupole time-of-flight tandem mass spectrometry (LC-ESI-QToF-MS/MS). The results demonstrate that UAE parameters have a pronounced influence on the antioxidant activity, TPC, and individual polyphenolic profile of green tea herbal dust extracts. Ethanol–water mixtures at a ratio of around 40–60%, as well as moderate impulse regimes (around 60%) and extraction times (around 10 min), were the most suitable for extracting green tea polyphenols. Epigallocatechin gallate was the predominant phenolic component in most extracts, alongside epicatechin, epigallocatechin, catechin, and gallic acid. The findings highlight the UAE technique as a robust, green, and scalable method for valorising green tea by-products, thereby facilitating the development of high-value natural extracts for applications in the food, pharmaceutical, and cosmetic industries. Full article