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Search Results (156)

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Keywords = ash constituents

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15 pages, 870 KB  
Article
Phytochemical Profiles and Antimicrobial Activity of Alnus glutinosa (L.) Gaertn. Leaves Growing in Kazakhstan
by Aliya Bazargaliyeva, Janar Jenis, Yergazy Shybyray, Gulnur Admanova, Zhaidargul Kuanbay, Samal Duzelbayeva, Balzat Sarimbayeva, Gulzhakhan Kaisagaliyeva, Bagdagul Alzhanova and Rima Kozhagaliyeva
Molecules 2026, 31(7), 1189; https://doi.org/10.3390/molecules31071189 - 3 Apr 2026
Viewed by 460
Abstract
Alnus glutinosa (L.) Gaertn. has extensive use in traditional medicine and diverse biological activities due to its rich phytochemical profile. In this study, firstly, the physicochemical characteristics of the plant material were evaluated, revealing a high content of extractive substances (17.684%), followed by [...] Read more.
Alnus glutinosa (L.) Gaertn. has extensive use in traditional medicine and diverse biological activities due to its rich phytochemical profile. In this study, firstly, the physicochemical characteristics of the plant material were evaluated, revealing a high content of extractive substances (17.684%), followed by ash (6.740%) and moisture (5.000%). Among the bioactive constituents, tannins were the most abundant (7.439%). Analysis of macroelements in the plant ash showed K (11.4330 mg/g) as the predominant element, followed by Mg (97.13 mg/g), Ca (75.30 mg/g), and Na (72.41 mg/g). Trace element analysis indicated Fe (1.2266 mg/g) as the most abundant microelement, with Zn (0.8870 mg/g) and Mn (0.8141 mg/g) present in comparable amounts. Gas chromatography–mass spectrometry (GC-MS) analysis of the ethanolic leaf extract characterized volatile and semi-volatile constituents of 43 phytochemical components, where vitamin E was the predominant compound (20.52%), followed by phytol (12.46%) and squalene (10.29%). Further high-performance liquid chromatography (HPLC) analysis confirmed the presumed presence of naringin (56.421 mg/L), followed by epicatechin (15.123 mg/L), catechin (12.485 mg/L), and phloridzin (11.800 mg/L), while gallic acid was detected at a comparatively lower concentration (0.402 mg/L). The antimicrobial activity of the aqueous leaf extract was evaluated against typical Gram-positive and Gram-negative pathogens, including Staphylococcus aureus, Salmonella abony, Escherichia coli, and Klebsiella pneumoniae. To evaluate the effect of compositional changes on antimicrobial activity, the fermented and non-fermented formulations of A. glutinosa leaf extracts were prepared. These results demonstrate measurable antibacterial effects, thereby confirming the ethnopharmacological significance of A. glutinosa and highlighting its potential as a source of natural antimicrobial agents for further pharmacological development. Full article
(This article belongs to the Section Natural Products Chemistry)
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18 pages, 2732 KB  
Article
Melipona quadrifasciata Geopropolis Extract as a Modulator of Inflammation and Pro-Regenerative Responses in Human Macrophages
by Luiza Naemi Koga Zapotoski, Maria Carolina de Oliveira Ribeiro, Marcelo José Pena Ferreira, Denise V. Tambourgi and Paula Cristiane Pohl
Int. J. Mol. Sci. 2026, 27(7), 3229; https://doi.org/10.3390/ijms27073229 - 2 Apr 2026
Viewed by 670
Abstract
Geopropolis, a complex natural product composed of propolis, wax, plant resins, and soil produced by Meliponine (stingless) bees, has traditionally been used for its therapeutic properties. Its chemically diverse composition and broad biological activities have recently attracted growing scientific interest. In this study, [...] Read more.
Geopropolis, a complex natural product composed of propolis, wax, plant resins, and soil produced by Meliponine (stingless) bees, has traditionally been used for its therapeutic properties. Its chemically diverse composition and broad biological activities have recently attracted growing scientific interest. In this study, we characterized the physicochemical and immunomodulatory properties of a hydroalcoholic extract of geopropolis (HEG) from Melipona quadrifasciata (Mandaçaia). Physicochemical characteristics were determined by measuring moisture, ash, and wax content, and its bioactive constituents were identified by GC–MS. THP-1-derived macrophages were exposed to increasing HEG concentrations to assess cytotoxicity, and two sublethal doses were selected for immunomodulatory assays with or without LPS stimulation. Cytokine and chemokine secretion were quantified by CBA, and the expression of key immunoregulatory and angiogenic genes was evaluated by RT-qPCR. Chemical profiling revealed a high wax content and a predominance of di- and triterpenoids, largely derived from coniferous sources. In mccrophages stimulated with LPS, HEG at 31.25 and 62.50 µg/mL significantly reduced the secretion of pro-inflammatory mediators (IL-6, CCL2, CCL5, CXCL9, and CXCL10) while preserving cell viability. In unstimulated macrophages, HEG upregulated the expression of genes VEGFA and TGFB1 as well as the protein CXCL8, all of them associated with angiogenesis and tissue repair. These findings demonstrate that M. quadrifasciata geopropolis extract modulates macrophage activity, promoting a shift toward a reparative phenotype that integrates inflammatory resolution with pro-healing effects. These results underscore its pharmacological potential as a terpenoid-rich natural product with complementary anti-inflammatory and regenerative activities. Full article
(This article belongs to the Special Issue Natural-Derived Bioactive Compounds in Disease Treatment)
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19 pages, 4453 KB  
Article
Sustainable Valorisation of Hazardous MSWI Air Pollution Control Fly Ash in Portland Composite Cement: Performance, Environmental Safety and Circular Economy Perspective
by Beata Łaźniewska-Piekarczyk and Monika Czop
Sustainability 2026, 18(7), 3322; https://doi.org/10.3390/su18073322 - 29 Mar 2026
Viewed by 426
Abstract
The management of hazardous municipal solid waste incineration (MSWI) residues represents a critical challenge for sustainable development due to their increasing generation and environmental risk. At the same time, the cement industry faces urgent pressure to reduce CO2 emissions associated with clinker [...] Read more.
The management of hazardous municipal solid waste incineration (MSWI) residues represents a critical challenge for sustainable development due to their increasing generation and environmental risk. At the same time, the cement industry faces urgent pressure to reduce CO2 emissions associated with clinker production, creating a demand for alternative supplementary cementitious materials. The aim of this study was to evaluate the feasibility of valorising hazardous municipal solid waste incineration (MSWI) air pollution control fly ash (EWC 19 01 07*) as a constituent of Portland composite cement, in line with circular economy principles and the need to reduce CO2 emissions associated with clinker production. The investigated fly ash, originating from flue gas cleaning processes, is characterised by high alkalinity and elevated concentrations of heavy metals, which currently necessitate controlled landfilling. To enable its safe reuse, the ash was subjected to high-temperature thermal treatment following granulation and subsequently incorporated into cement formulations under semi-industrial conditions. Two Portland composite cements were produced with different ash contents, corresponding to CEM II/A-07 and CEM II/B-07, while a Portland cement manufactured from the same clinker was used as a reference material. The chemical and phase composition of the ash before and after thermal treatment was analysed using XRF and XRD, supported by SEM/EDS observations. The results demonstrate that thermal treatment at 1150 °C induces partial phase stabilisation of APC fly ash without full vitrification, allowing its integration into cement systems under semi-industrial conditions. The incorporation of ash significantly alters hydration behaviour through increased water demand governed by particle porosity, CaO-rich phase composition, and early ionic interactions in the pore solution, leading to reduced workability and mechanical performance. While immobilisation efficiencies exceeding 99.5% were achieved for most heavy metals due to precipitation and incorporation into hydration products, barium exhibited persistent leaching controlled by its solubility under highly alkaline conditions and limited incorporation into C–S–H phases. These findings define both the technological feasibility and the key environmental constraints of APC fly ash utilisation in Portland composite cement. From a sustainability perspective, the proposed approach contributes to the reduction in hazardous waste landfilling and supports clinker substitution in cement production. The results demonstrate the potential of integrating waste management and low-carbon material design within a circular economy framework while highlighting current environmental limitations related to barium leaching. Full article
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31 pages, 16922 KB  
Review
Recycle and Reuse of Calcium-Rich Waste in Brownfield: Review of Practices of Sludge Pond Reuse, Upper Kama Region (Russia)
by Evgeniya Ushakova, Elena Kalinina, Pavel Belkin, Elena Menshikova, Sergey Blinov, Roman Perevoshchikov and Vladimir Pugach
Mining 2026, 6(1), 24; https://doi.org/10.3390/mining6010024 - 17 Mar 2026
Viewed by 706
Abstract
The organization of safe industrial waste management is an integral part of the global sustainable development strategy. This study provides a preliminary assessment of the processing and recycling potential of strongly alkaline (pH 11–12) sediments accumulated in an abandoned sludge pond (Berezniki, Perm [...] Read more.
The organization of safe industrial waste management is an integral part of the global sustainable development strategy. This study provides a preliminary assessment of the processing and recycling potential of strongly alkaline (pH 11–12) sediments accumulated in an abandoned sludge pond (Berezniki, Perm Krai, Russia), based on the initial characterization of their material composition. Sediment samples from the sludge pond were collected, layer-by-layer, over the entire depths of four sediment cores. The collected samples have the following characteristics: sediment particles are composed of up to 80% fine particles < 0.05 mm, with up to 20% fine particles < 0.002 mm. XRD data showed that the sediment consisted of calcite (67.7 wt.%), halite (11.5 wt.%), and other hydrogenic and terrigenous minerals. XRF data also found that the primary constituents in the sediment are CaO (up to 40%), Cl (up to 13%), and LOI (up to 35%). The results of the material composition study indicate a high degree of similarity between the accumulated sediments and solid waste from soda ash production, known as ammonia–soda residue (ASR). Based on experience with calcium-containing waste, this study recommends options for the secondary use of sludge, identifying two main possibilities: environmental protection and construction. We have developed an algorithm for the recycling and reuse of sludge that identifies risks, limitations, and recommended next steps. However, significant knowledge gaps regarding the environmental, toxicological, and the physical–mechanical properties of sludge prevent us from recommending a specific disposal option. The results of this review will serve as guidelines to help develop a roadmap for the disposal process. They will also inform decision-makers about sustainability issues related to industrial waste disposal. Full article
(This article belongs to the Topic Environmental Pollution and Remediation in Mining Areas)
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21 pages, 5114 KB  
Article
Fly Ash and Bottom Ash from Biomass and Coal: Comparison of Properties in Grate and Fluidized Bed Combustion from the Perspective of Construction Applications
by Karolína Králová, Petr Formáček, Martina Šídlová, Rostislav Šulc, Lukáš Mauermann, Klára Betáková and Jan Konvalinka
Sustainability 2026, 18(5), 2592; https://doi.org/10.3390/su18052592 - 6 Mar 2026
Viewed by 731
Abstract
The cement industry seeks alternative raw materials to lower its environmental impact, and biomass ash represents a potential material for construction applications. This study evaluates biomass ashes (BMA) produced from grate and fluidized bed combustion, as well as co-combustion with coal, focusing on [...] Read more.
The cement industry seeks alternative raw materials to lower its environmental impact, and biomass ash represents a potential material for construction applications. This study evaluates biomass ashes (BMA) produced from grate and fluidized bed combustion, as well as co-combustion with coal, focusing on their chemical, mineralogical, and physical characteristics. The results reveal a substantial variability in BMA composition, influenced primarily by the fuel type and combustion method. This heterogeneity critically affects the reactivity and overall suitability of the BMA for use in construction materials. It was found that none of the 23 analyzed samples met the requirements of EN 450-1. This outcome is largely attributable to the combustion process and to sampling from the bottom part of the boiler, which typically yields material with properties outside the limits of the standard. Even when assessed directly against the specific limit values of EN 450-1, the ashes did not comply without further processing or modification. Despite these limitations, BMA show potential for use in accordance with EN 197-1, which permits the incorporation of up to 5 wt.% minor additional constituents. However, their practical application under this framework requires validation through tests performed on hydrated cement. These findings underline both the limitations and the promise of BMA as a supplementary cementitious material (SCMs) in sustainable construction. Full article
(This article belongs to the Special Issue Utilization of Biomass: Energy, Catalysts, and Applications)
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15 pages, 667 KB  
Article
Durability of Concrete Made with Coal Bottom Ash Portland Cements
by Natalia Sanjuán, Silvia Grandes, Miguel Ángel Sanjuán, Pedro López and Aniceto Zaragoza
Materials 2026, 19(4), 773; https://doi.org/10.3390/ma19040773 - 16 Feb 2026
Viewed by 517
Abstract
The Portland cement industry, responsible for approximately 7.4% of global anthropogenic carbon dioxide emissions, must balance rising cement demand with ambitious greenhouse gas reduction targets. In parallel, the rapid accumulation of industrial solid waste highlights the need for effective valorization routes. Reducing the [...] Read more.
The Portland cement industry, responsible for approximately 7.4% of global anthropogenic carbon dioxide emissions, must balance rising cement demand with ambitious greenhouse gas reduction targets. In parallel, the rapid accumulation of industrial solid waste highlights the need for effective valorization routes. Reducing the clinker factor remains a powerful measure to mitigate climate impacts in the cement sector. This study evaluates the durability of concretes made with ground coal bottom ash (CBA), a newly standardized Portland cement constituent, using the depth of penetration of water under pressure test (EN 12390-8). The experimental results show that concretes produced with CEM II/B-Z and CEM II/C-M cements meet both average (≤30 mm) and maximum (≤50 mm) water penetration criteria for mass, reinforced, and prestressed concrete across all EN 206-1 exposure classes. Concretes made with CEM VI (S-L) and CEM VI (S-Z) comply for XS1, XS2, XD, XA1, XM, and XF classes. However, for XS3, XA2, and XA3, compliance (≤20 mm and ≤30 mm) is not achieved when using mix design B (300 kg/m3, w/c = 0.50). These findings provide robust technical evidence supporting CBA as a viable cement constituent that enhances durability while enabling clinker factor reduction. Full article
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21 pages, 9081 KB  
Article
Rumen Fluid Transplantation from Allium mongolicum Regel-Fed Donors Enhances Lamb Meat Quality and Reduces 4-Alkyl Branched-Chain Fatty Acids
by Xiaoyuan Wang, Guoli Han, Khas Erdene, Chen Bai, Qina Cao, Yankai Zheng, Terigele Li, Lahan Hai, Yande Fan, Yuqi Zhao, Xinyi Liu and Changjin Ao
Foods 2026, 15(4), 701; https://doi.org/10.3390/foods15040701 - 13 Feb 2026
Cited by 4 | Viewed by 465
Abstract
The extent of consumer approval for lamb is intimately connected to meat quality standards. Within this context, the distinctive ‘mutton taint’ serves as a critical benchmark for assessment, a characteristic that is largely governed by the concentrations of three fundamental branched-chain fatty acids [...] Read more.
The extent of consumer approval for lamb is intimately connected to meat quality standards. Within this context, the distinctive ‘mutton taint’ serves as a critical benchmark for assessment, a characteristic that is largely governed by the concentrations of three fundamental branched-chain fatty acids (KBCFA), specifically 4-methyloctanoic acid (MOA), 4-ethyloctanoic acid (EOA), and 4-methylnonanoic acid (MNA). While Allium mongolicum Regel (AMR)—an Allium species prevalent in arid Asian regions known for its abundant bioactive constituents—is known to improve meat quality and mitigate these off-flavors, the potential mediating role of the rumen fluid in this process remains unclear. This study investigated whether rumen fluid transplantation (RFT) from AMR-fed donors could mimic the impacts of directly adding AMR to the diet on KBCFA accumulation and meat attributes. Thirty male lambs (23 ± 2 kg BW) were allocated at random into three distinct treatments (n = 10): a control set (CON), a dietary supplementation group administered 15 g/d of AMR (AMG), along with a rumen fluid transplantation treatment (RTG) inoculated with rumen fluid from AMR-fed donors. The carcass traits, physicochemical properties, and makeup of amino acids, as well as the fatty acid constitution of the longissimus thoracis muscle, were subjected to analysis. Data revealed that the levels of KBCFAs associated with off-flavors were markedly lowered in both the AMG and RTG. Specifically, decreases ranging from 49% to 64% were observed in MOA, EOA, and MNA concentrations (p < 0.05). Relative to the control group, drip loss and cooking loss were reduced in the treatment groups (p < 0.05), whereas ash (p = 0.047) and crude protein (p = 0.001) were increased. Moreover, the interventions improved the composition of essential amino acids (EAA), flavor-enhancing amino acids, and polyunsaturated fatty acids (PUFAs). In conclusion, rumen fluid transplantation effectively replicates the beneficial effects of dietary AMR on meat quality, particularly in reducing taint-related KBCFA. Such outcomes imply that rumen microbial communities likely act as a crucial mediator in controlling meat flavor. Full article
(This article belongs to the Section Meat)
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27 pages, 8668 KB  
Article
Feasibility-Oriented Assessment of Physical Modeling Approaches for Shaking Table Testing of RC Minarets
by Louay Karaker and Erdem Damcı
Appl. Sci. 2026, 16(2), 990; https://doi.org/10.3390/app16020990 - 19 Jan 2026
Viewed by 341
Abstract
Slender structures such as minarets are highly susceptible to earthquake-induced damage in seismically active regions. Although various methods, including analytical and observational techniques, have been employed to study the seismic response of reinforced concrete (RC) minarets, the use of scaled physical models and [...] Read more.
Slender structures such as minarets are highly susceptible to earthquake-induced damage in seismically active regions. Although various methods, including analytical and observational techniques, have been employed to study the seismic response of reinforced concrete (RC) minarets, the use of scaled physical models and shaking table testing remains limited. This research examines the numerical feasibility of employing scaled physical models for shaking table investigations of RC minarets under realistic laboratory constraints. A representative RC minaret with a height of 33.2 m was selected and a geometric scale ratio of 1:10 length was adopted. Established physical modeling approaches were evaluated through numerical implementation, with particular attention to similitude requirements, material properties, and laboratory limitations. Within this framework, the Artificial Mass Model (AMM) and the Neglected Gravity Model (NGM) were examined as candidate strategies for scaled modeling. Both approaches necessitate the use of a material with a reduced modulus of elasticity or an increased mass density relative to the prototype material. To satisfy these requirements, two micro-concrete mixes, designated as Mix-1 and Mix-2, incorporating partial replacement of the binder with lower-stiffness constituents such as plaster gypsum and fly ash, were developed and characterized. Numerical results indicate that both the AMM and NGM approaches are viable for modeling slender RC minaret structures. Although the AMM provides slightly higher accuracy in reproducing the prototype dynamic response, the NGM offers greater practical applicability by eliminating the need for additional artificial mass. Overall, this study presents a preliminary numerical feasibility assessment that supports the selection of appropriate physical modeling strategies and provides a rational basis for the subsequent execution of shaking table experiments. Full article
(This article belongs to the Section Civil Engineering)
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24 pages, 4356 KB  
Article
Design of Recycled Aggregate Fiber-Reinforced Concrete for Road and Airfield Applications Using Polypropylene Fibers and Fly Ash
by Vitalii Kryzhanovskyi, Sergii Kroviakov, Pavlo Shymchenko and Inna Aksyonova
Constr. Mater. 2026, 6(1), 2; https://doi.org/10.3390/constrmater6010002 - 5 Jan 2026
Cited by 3 | Viewed by 916
Abstract
Driving the circular economy in road construction requires the effective use of secondary materials like recycled concrete aggregate (RCA) and fly ash (FA). A key obstacle is the performance trade-off in concretes incorporating both materials. This research investigates feasible mix designs for road [...] Read more.
Driving the circular economy in road construction requires the effective use of secondary materials like recycled concrete aggregate (RCA) and fly ash (FA). A key obstacle is the performance trade-off in concretes incorporating both materials. This research investigates feasible mix designs for road concrete, using RCA as a full gravel replacement and FA as a cement substitute. Polypropylene fiber (36 mm) and a superplasticizer were utilized to mitigate fresh and hardened state drawbacks. The experimental program included 15 modified mixtures with recycled aggregate and 3 control mixtures with natural aggregate. The workability of all concrete mixtures was kept constant at slump class S1. Road concretes with RCA, containing a 10–12% FA by cement replacement, at least 2 kg/m3 of polypropylene fiber (PF), and 4 kg/m3 of superplasticizer (SP), achieve compressive strength of at least 50 MPa and flexural strength of no less than 5 MPa at the design age. This performance is comparable to that of control mixtures. Furthermore, the abrasion resistance ranges between 0.48–0.50 g/cm2, and the brittleness index falls within 0.095–0.100, significantly enhancing the durability of concrete for rigid pavement applications. The conducted cradle-to-gate life-cycle assessment (stages A1–A3) of the constituent materials for 1 m3 of concrete indicates the following environmental impacts: Global Warming Potential (GWP) of 195 kg CO2 equation, Non-renewable Primary Energy Demand (PENRE) of 1140 MJ, Abiotic Depletion Potential for Fossil resources (ADPF) of 1120 MJ, Acidification Potential (AP) of 0.45 mol H+ equation, and Eutrophication Potential (EP) of 0.07 kg PO43− equation It is established that the modified compositions not only meet the required performance criteria but also contribute to the goals of resource conservation in road construction. Full article
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28 pages, 11072 KB  
Article
Evaluating Coal Quality and Trace Elements of the Karagandy Coal Formation (Kazakhstan): Implications for Resource Utilization and Industry
by Medet Junussov, Geroy Zh. Zholtayev, Ahmed H. Moghazi, Yerzhan Nurmakanov, Mohamed Abdelnaby Oraby, Zamzagul T. Umarbekova, Moldir A. Mashrapova and Kuanysh Togizov
Resources 2026, 15(1), 5; https://doi.org/10.3390/resources15010005 - 25 Dec 2025
Cited by 3 | Viewed by 1233
Abstract
The Carboniferous coal seams in Northeast Kazakhstan remain insufficiently investigated, with a lack of comprehensive mineralogical and geochemical assessments necessary to understand the geological processes controlling coal quality. This study examines 15 coal samples from the Karagandy Coal Formation (KCF) at the Saradyr [...] Read more.
The Carboniferous coal seams in Northeast Kazakhstan remain insufficiently investigated, with a lack of comprehensive mineralogical and geochemical assessments necessary to understand the geological processes controlling coal quality. This study examines 15 coal samples from the Karagandy Coal Formation (KCF) at the Saradyr and Bogatyr mines using proximate and ultimate analyses, FTIR, XRD, SEM–EDS, ED-XRF, and ICP-OES, providing the first detailed comparison of mineralogical and geochemical characteristics—including depositional signals and inorganic constituent distribution—between these mines within the KCF. The coals exhibit an average ash yield of 24.1% on a dry basis, volatile matter of 21.6% on a dry and ash-free basis, and low moisture content of 1.1% (air-dry), with low sulfur levels of 0.7% in whole coal across both mines. Mineralogical composition is dominated by quartz and clay minerals, with minor pyrite, apatite, chalcopyrite, and rutile. Major oxides in the coal ash average 68.2% SiO2 and 19.5% Al2O3, followed by Fe2O3, K2O, and TiO2 (3–12.1%). Among the 24 identified trace elements, Sm is the most abundant at 6.3 ppm with slight enrichment (CC = 2.8), Lu remains at normal levels (CC < 1), and most other elements are depleted (CC < 0.5). The Al2O3/TiO2 ratios (3.8–10.8) indicate contributions from intermediate to mafic parent materials. The detrital mineralogy, parting compositions, and elevated ash content indicate significant accommodation space development during or shortly after peat accumulation, likely within a vegetated alluvial plain depression. These findings provide new insights into the depositional environment and coal-forming processes of the KCF and contribute to regional assessments of coal quality and resource potential. Full article
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25 pages, 5917 KB  
Article
Explainable Machine Learning-Based Prediction of Compressive Strength in Sustainable Recycled Aggregate Self-Compacting Concrete Using SHAP Analysis
by Ahmed Almutairi
Sustainability 2025, 17(24), 11334; https://doi.org/10.3390/su172411334 - 17 Dec 2025
Cited by 3 | Viewed by 1255
Abstract
The increasing emphasis on sustainability in construction materials has led to a surge of research focused on recycled aggregate self-compacting concrete (RA-SCC). However, the critical gap in predicting the compressive strength of concrete remains challenging because of the nonlinear interactions among the mix’s [...] Read more.
The increasing emphasis on sustainability in construction materials has led to a surge of research focused on recycled aggregate self-compacting concrete (RA-SCC). However, the critical gap in predicting the compressive strength of concrete remains challenging because of the nonlinear interactions among the mix’s constituents. The distinct contribution of this study is to develop an interpretable machine learning (ML) framework to accurately forecast the compressive strength of RA-SCC and identify the most influential mix parameters. A dataset comprising 400 experimental samples was compiled, incorporating eight input variables: age, cement strength, cement, fly ash, blast furnace slag, water, recycled aggregate, and superplasticizer, with compressive strength as the output variable. Four ML algorithms such as support vector regression (SVR), random forest (RF), Multilayer Perceptron (MLP), and extreme gradient boosting (XGBoost) were trained and optimized using Bayesian-based hyperparameter tuning combined with 10-fold cross-validation. Among the evaluated models, XGBoost demonstrated superior accuracy, with R2 = 0.98 and RMSE = 2.95 MPa during training, and R2 = 0.96 with RMSE = 3.25 MPa during testing, confirming its robustness and minimal overfitting. SHAP (SHapley Additive exPlanations) evaluation indicates that superplasticizer, cement, and cement strength were the most dominant factors influencing compressive strength, whereas higher water content showed a negative impact. The developed framework demonstrates that explainable ML can effectively capture the complex nonlinear behavior of RA-SCC, offering a reliable tool for mix design optimization and sustainable concrete production. These findings contribute to advancing data-driven decision making in eco-efficient materials engineering. Full article
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16 pages, 820 KB  
Article
Sustainable Recovery of Valuable Constituents from Octopus (Octopus vulgaris) Cooking Liquor
by Ricardo Prego, Antonio Cobelo-García, Marcos Trigo, Susana Calvo and Santiago P. Aubourg
Sustainability 2025, 17(21), 9391; https://doi.org/10.3390/su17219391 - 22 Oct 2025
Viewed by 983
Abstract
Cooking liquor (CL) from marine species processing has been reported to include a wide range of valuable constituents. In this study, the chemical composition of CL from octopus (Octopus vulgaris) processing, with and without a filtration process, was analysed. Regarding non-filtered [...] Read more.
Cooking liquor (CL) from marine species processing has been reported to include a wide range of valuable constituents. In this study, the chemical composition of CL from octopus (Octopus vulgaris) processing, with and without a filtration process, was analysed. Regarding non-filtered CL, values of 15.30, 0.29, 8.85 and 174.53 g·L−1 CL for protein, lipids, ash, and total volatile base-nitrogen (TVB-N), respectively, were detected. The most abundant fatty acids (FAs) (g·100 g−1 total FAs) were C16:0 (37.8), C18:0 (20.8), and C22:6ω3 (13.4). Values of 0.40 and 2.10 were obtained for polyunsaturated FA/saturated FA and ω3 FA/ω6 FA ratios. Macroelement content varied from 0.036 (Ca) to 1.81 (Na) g·L−1 CL. For microelements, values ranged between 0.0015 (Co) and 1.95 (As) mg·L−1 CL. Industrial filtration of CL led to decreased values of protein, lipid, ash, TVB-N, and C22:5ω3; in contrast, an increased presence of C14:0, C18:1ω9, C20:1ω9, and C22:1ω9 was detected. Filtration led to a ca. 50% decrease in macroelement presence. For microelements, this process led to losses of 20–40% (Ba, Pb), 40–60% (As, Fe, Mn), 60–70% (Co, Zn), and 84% (Cd). This study provides a first comprehensive characterisation of octopus cooking liquor as a potential source of bioactive compounds. Full article
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20 pages, 7623 KB  
Article
Comparative Assessment of Cement and Geopolymer Immobilization Approaches: Short-Term Leaching Performance of Thermally Treated Ion Exchange Resin Waste Forms
by Raúl Fernández, Pedro Perez-Cortes, Esther Irene Marugán, Pilar Padilla-Encinas, Francisca Puertas, Inés García-Lodeiro, Ana Isabel Ruiz, Jaime Fernando Cuevas, María Jesús Turrero, María Cruz Alonso and Elena Torres
Appl. Sci. 2025, 15(20), 11196; https://doi.org/10.3390/app152011196 - 19 Oct 2025
Cited by 1 | Viewed by 1360
Abstract
Cementation using Ordinary Portland Cement (OPC) remains the standard method for conditioning low- and intermediate-level radioactive waste, including Spent Ion Exchange Resins (SIERs). This work presents an integrated strategy involving thermal pretreatment to minimize waste volume and eliminate organic constituents, followed by encapsulation [...] Read more.
Cementation using Ordinary Portland Cement (OPC) remains the standard method for conditioning low- and intermediate-level radioactive waste, including Spent Ion Exchange Resins (SIERs). This work presents an integrated strategy involving thermal pretreatment to minimize waste volume and eliminate organic constituents, followed by encapsulation within three distinct binders: CEM I, CEM III, and a novel one-part geopolymer. The one-part geopolymer system represents a significant operational innovation, enabling safe and simple “just-add-water” processing and avoiding the need to handle alkaline solutions. The proposed geopolymer, synthesized from metakaolin, blast furnace slag, and solid sodium silicate, was systematically benchmarked against conventional OPC matrices (CEM I, CEM III) by assessing their capacity to immobilize thermally treated SIER ashes under accelerated leaching conditions. For benchmarking, leaching indices for Cs and Sr were determined following the ANSI/ANS 16.9 standard protocol in three representative environments simulating operational and long-term repository scenarios, providing a quantitative evaluation of radionuclide retention and matrix durability. Results indicate that the one-part geopolymer improved leaching indices for Cs and Sr compared to both cementitious binders and complied with regulatory waste acceptance criteria. The comparative results highlight the potential of geopolymer technology to increase waste loading efficiencies and improve long-term safety, establishing a robust framework for future radioactive waste management approaches. Full article
(This article belongs to the Special Issue Radioactive Waste Treatment and Environment Recovery)
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37 pages, 2119 KB  
Review
Recycled Components in 3D Concrete Printing Mixes: A Review
by Marcin Maroszek, Magdalena Rudziewicz and Marek Hebda
Materials 2025, 18(19), 4517; https://doi.org/10.3390/ma18194517 - 28 Sep 2025
Cited by 5 | Viewed by 3863
Abstract
Rapid population growth and accelerating urbanization are intensifying the demand for construction materials, particularly concrete, which is predominantly produced with Portland cement and natural aggregates. This reliance imposes substantial environmental burdens through resource depletion and greenhouse gas emissions. Within the framework of sustainable [...] Read more.
Rapid population growth and accelerating urbanization are intensifying the demand for construction materials, particularly concrete, which is predominantly produced with Portland cement and natural aggregates. This reliance imposes substantial environmental burdens through resource depletion and greenhouse gas emissions. Within the framework of sustainable construction, recycled aggregates and industrial by-products such as fly ash, slags, crushed glass, and other secondary raw materials have emerged as viable substitutes in concrete production. At the same time, three-dimensional concrete printing (3DCP) offers opportunities to optimize material use and minimize waste, yet it requires tailored mix designs with controlled rheological and mechanical performance. This review synthesizes current knowledge on the use of recycled construction and demolition waste, industrial by-products, and geopolymers in concrete mixtures for 3D printing applications. Particular attention is given to pozzolanic activity, particle size effects, mechanical strength, rheology, thermal conductivity, and fire resistance of recycled-based composites. The environmental assessment is considered through life-cycle analysis (LCA), emphasizing carbon footprint reduction strategies enabled by recycled constituents and low-clinker formulations. The analysis demonstrates that recycled-based 3D printable concretes can maintain or enhance structural performance while mix-level (cradle-to-gate, A1–A3) LCAs of printable mixes report CO2 reductions typically in the range of ~20–50% depending on clinker substitution and recycled constituents—with up to ~48% for fine recycled aggregates when accompanied by cement reduction and up to ~62% for mixes with recycled concrete powder, subject to preserved printability. This work highlights both opportunities and challenges, outlining pathways for advancing durable, energy-efficient, and environmentally responsible 3D-printed construction materials. Full article
(This article belongs to the Special Issue Research on Alkali-Activated Materials (Second Edition))
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Review
Nutritional and Phytochemical Characterization of Radish Leaves: A Comprehensive Overview
by Xiong Geng, Ziyi Gong, Weina Tian, Miaomiao Zhuang, Huayan Shang, Yujie Chen, Jianrong Li, Yanfang Lv and Kaihua Bai
Foods 2025, 14(18), 3270; https://doi.org/10.3390/foods14183270 - 20 Sep 2025
Cited by 4 | Viewed by 6322
Abstract
Radish is a root vegetable that is widely consumed globally. Radish leaves are typically not consumed and regarded as by-products in agricultural, industrial, and domestic settings. Accumulating evidence suggests that radish leaves possess higher nutritional value compared to their roots, primarily due to [...] Read more.
Radish is a root vegetable that is widely consumed globally. Radish leaves are typically not consumed and regarded as by-products in agricultural, industrial, and domestic settings. Accumulating evidence suggests that radish leaves possess higher nutritional value compared to their roots, primarily due to their elevated levels of protein, ash, dietary fiber, and ascorbic acid. In light of the growing emphasis on waste reduction and value-added utilization, the application of radish by-products has garnered increasing attention. This study comprehensively reviews the phytochemical composition and pharmacological effects of radish leaves, a common agricultural by-product, detailing the structures of isolated compounds and discussing their chemical properties and bioactivities. When classified by their structural characteristics, these compounds encompass carbohydrates, enzymes, flavonoids, glucosinolates, organic acids, phenolic compounds, sulfur compounds, polysaccharides, and other constituents. Key bioactive components exhibit antioxidant properties, acetylcholinesterase inhibitory activity, antitussive effects, along with anticancer, antihypertensive, anti-inflammatory, antimicrobial, anti-obesity, antiulcerative, and intestinal motility stimulation activities. Radish leaf extracts demonstrate significant therapeutic potential across multiple disease areas, particularly in anticancer and antioxidant applications. Full article
(This article belongs to the Section Food Nutrition)
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