Search Results (718)

This study presents a comprehensive and integrated characterization of solid and liquid residues generated during industrial glass-cutting operations, highlighting the novelty of treating glass-cutting sludge and process wastewater as compositionally linked outputs of the same industrial comminution process. The research examined the morphology, elemental composition, and selected physicochemical properties of sludge and wastewater-derived particulates to assess material-recovery potential and provide a basis for further evaluation of water reuse. Samples were analyzed using particle morphology assessment, scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS), Fourier-transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR), dynamic light scattering (DLS), and pH measurements. The results showed that the solid fraction consisted predominantly of soda–lime–silica glass constituents, with oxygen, silicon, sodium, calcium, and magnesium as the main components, while potentially problematic contaminants remained at low levels. Although isolated particles enriched in Fe, Cu, Ni, Sn, La, or Ce were detected, their occurrence was limited and did not significantly affect the average particulate composition observed within the SEM-EDS dataset. This is particularly important for coated glass, where functional coatings contribute negligibly to the bulk glass matrix. From a material-recovery perspective, the sludge should be regarded as a promising glass-derived mineral residue requiring further route-specific qualification rather than as waste intended solely for disposal. However, this study does not demonstrate suitability for any specific reuse route, and additional validation is needed regarding compositional consistency, variability, moisture and organic content, leaching behavior, and route-specific acceptance criteria. For process wastewater, contamination was governed mainly by suspended glass-derived solids, indicating that solid–liquid separation is the key treatment step. However, the present dataset is insufficient to confirm the suitability of treated water for direct industrial recirculation, and the results should therefore be interpreted as indicating potential for further evaluation after appropriate clarification. This work establishes an empirical multi-scale characterization framework that links glass-cutting sludge and process wastewater as compositionally related outputs of the same comminution process, thereby supporting circular-economy strategies by jointly informing sludge valorization and water-clarification pathways. Overall, this work establishes a multiscale characterization framework for integrated residue management, jointly supporting sludge valorization and wastewater clarification assessment within a circular-economy perspective. Full article

This study investigates the effects of phosphorus (P) on the phases developed during sintering and their impact on the stability of key phases in iron ore sinter, particularly the silico-ferrite of calcium and aluminum (‘SFCA’) series of phases. Two complementary systems were studied: an industrially representative blend of natural iron ores (JSM) and a synthetic high-purity SFCA analogue (SA) system designed to promote controlled SFCA formation. Phosphorus was added as hydroxyapatite (HA) at levels of 0.5, 1.0, 1.5 and 5 wt.%. To simulate a standard sintering profile, experiments were conducted over a range of temperatures for 3 min in a controlled low-oxygen-potential atmosphere of pO₂ = 5 × 10⁻³ atm. A modified Bond Abrasion test was used to evaluate the tumble index (TI) strength of the samples, and the chemistry, mineralogy and microstructure of all sintered products were analyzed. Results indicated that all P-doped JSM samples fired within the temperature range of 1300 to 1330 °C met the minimum strength requirement (TI = 80%) for producing high-quality sinters. Adding small to medium amounts of HA (≤1.5 wt.%) to both compositions had a limited impact on the overall mineral phases. Conversely, adding a high amount of HA (5 wt.%) encouraged the creation of Ca–Si–P phases. Analysis of the microstructure, minerals, and microchemistry indicated that P tended to segregate phases rich in phosphorus by interacting with calcium oxide and silica. The findings from the study highlight that at the low levels of P typically found in iron ores, there is no significant impact on the strength, mineralogy and phases formed during sintering. Full article

Eutrophication in tropical endorheic lakes often persists despite reductions in external nutrient inputs, indicating an important role of internal nutrient loading. However, integrated evidence linking thermal stratification, sediment characteristics, and sediment-derived nutrient release in tropical endorheic lakes remains limited. This study investigated the mechanisms contributing to eutrophication in Lake Batur, a tropical endorheic volcanic lake in Indonesia, through seasonal water-column observations, sediment porewater profiling, diffusive nutrient flux analysis, and sediment characterization. Seasonal observations showed thermal stratification accompanied by hypoxic to anoxic bottom waters, while sediment-derived nutrient flux was dominated by ammonium and phosphate under reducing conditions. Sediment characterization at the representative sampling site revealed mineral assemblages dominated by biogenic silica, aluminosilicate clays, carbonates, and iron-bearing phases that may influence nutrient mobility under low-oxygen conditions. The results indicate strong coupling between thermal stratification, hypolimnetic oxygen depletion, and sediment–water interactions, suggesting that internal loading contributes to maintaining eutrophic conditions in Lake Batur. The endorheic nature of the lake likely enhances nutrient retention because of limited hydrological flushing and prolonged nutrient residence times. These findings improve understanding of eutrophication processes in tropical endorheic volcanic lakes and highlight the importance of considering sediment-derived internal loading together with external nutrient reduction in lake restoration strategies. Full article

The development of reusable nanomaterials for the extraction of trace-metals from complex matrices remains challenging because strong metal-chelating functionalities often hinder desorption and regeneration, whereas weaker binding sites compromise selectivity and enrichment efficiency. This limitation has been addressed by designing a ligand-engineered fibrous mesoporous silica nanomaterial (Van-KCC-1) via the integration of the unique structural features of KCC-1 with an o-vanillin-derived Schiff-base chelator. The material was synthesized throughout the chemical grafting of 3-aminopropyltriethoxysilane (APTES) onto fibrous mesoporous silica KCC-1, followed by condensation with 3-methoxy-2-hydroxybenzaldehyde (o-vanillin). The successfulness of functionalization and Schiff-base formation were confirmed by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS). The radially oriented fibrous channels of KCC-1 provide a highly accessible surface that remains available for interaction with the targeted ions even after chemical modification. This architecture facilitates rapid mass transfer and efficient utilization of binding sites, while the incorporated Schiff-base ligand introduces imine, phenolic, and methoxy donor groups capable of selectively and reversibly coordinating Ni(II) and Cd(II). The resulting balance between adsorption strength and desorption efficiency enables both effective metal capture and sorbent reusability. More importantly, the study demonstrates how KCC-1 can serve as a versatile nanosilica scaffold for the incorporation of tailored chelating ligands without sacrificing structural accessibility. The functionalized nanomaterial was evaluated as a dispersive solid-phase extraction (DSPE) sorbent coupled with inductively coupled plasma optical emission spectrometry (ICP-OES). Under optimized conditions, linear ranges of 0.035–50 μg L⁻¹ for Ni(II) and 0.058–50 μg L⁻¹ for Cd(II) were obtained, with limits of detection of 0.011 and 0.019 μg L⁻¹, respectively. The method exhibited excellent precision (relative standard deviation ≤ 3.6%) and recoveries of 92.00–98.83% in certified reference materaisl (NIST CRM 1643d), mineral water, tap water and synthetic wastewater. In addition, the nanochelator has retained more than 87% of its initial sorption efficiency after six adsorption–desorption cycles and showed minimal interference from common coexisting ions. These findings establish Van-KCC-1 as an efficient, selective, and reusable DSPE sorbent in the determination of trace-metals while highlighting the broader potential of fibrous mesoporous silica KCC-1 as a platform for the rational design of next-generation chelated nanomaterials. Full article

Silicon (Si) is a beneficial, non-essential element used in cannabis (Cannabis sativa L.), yet cannabis-specific evidence is scattered across hemp and drug-type cannabis. Because the marketable organ in drug-type and medicinal cannabis is the inflorescence, whose cannabinoid and terpene quality and strict residue limits make every fertigation input unusually consequential, a cannabis-focused synthesis of silicon use is needed. This comprehensive review aims to synthesize that evidence and clarify when, how, and in what form Si supplementation is justified across the crop cycle, based on a four-database search (covering the literature up to May 2026, with the cannabis-specific evidence base spanning 2019–2026). Cannabis is an intermediate Si accumulator depositing silica in bast fibers and trichomes, with benefits clearest in propagation and vegetative growth. Root Si lowers cadmium and zinc uptake and supports antioxidant defense; foliar nano-Si aids drought tolerance, and Si suppresses powdery mildew while raising tissue Si ~2.1-fold and inflorescence biomass ~1.2-fold without reducing cannabinoid or terpene quality. On current evidence, Si appears best deployed as a resilience-enhancing, stage-specific input within an integrated program rather than a universal additive. Future research should prioritize genotype- or chemotype-resolved dose–response studies on cannabinoid and terpene yields and late-flower-application safety. Full article

The Yishu Fault Zone (YSFZ) is located in a key tectonic transition zone shaped by the interaction between the Pacific and Tethyan tectonic domains in eastern China. Despite sparse geothermal borehole coverage across this region, the deeply incised fault structures create favorable hydrogeological prerequisites for fault-mediated subsurface heat migration and hydrothermal fluid circulation. This study integrates hydrochemistry, multi-isotope tracing (δD, δ¹⁸O, ⁸⁷Sr/⁸⁶Sr, and δ³⁴S), multi-mineral equilibrium modeling, and silica–enthalpy mixing analysis to constrain the evolution process and genetic mechanism of geothermal groundwater in the middle segment of the YSFZ. The geothermal groundwater displays weakly alkaline to alkaline properties and in situ temperatures of 35.2~75.0 °C, which is characterized by the HCO₃–Na, SO₄–Na, and Cl·SO₄–Na type. Stable isotope signatures demonstrate that the geothermal groundwater is recharged by the atmospheric precipitation with elevations of 822~1274 m. The hydrochemical evolution of the geothermal waters is governed by silicate weathering, evaporite dissolution, and cation exchange. The ⁸⁷Sr/⁸⁶Sr ratios indicate mixed solute contributions from silicate and evaporite lithologies, whereas the δ³⁴S signatures suggest that SO₄²⁻ is predominantly derived from gypsum dissolution. Two distinct hydrochemical evolution patterns can be identified in the study area. Samples GG1 and GG5 are characterized by HCO₃⁻ enrichment, whereas GG2, GG3, and GG4 exhibit enrichment in Na⁺ and SO₄²⁻. Reservoir temperatures estimated using multi-mineral equilibrium geothermometry range from 56.7 °C to 92.1 °C, with circulation depths of 1648~2304 m and cold-water mixing ratios of 48%~69%. The results of this study provide geochemical evidence for hidden geothermal resource exploration in deep fault zones. Full article

The Upper Oligocene–Lower Miocene Alibonca Formation retains an essential record of intricate relationships among carbonate platform evolution, volcanic–sedimentary inflow, and high-purity silica deposition. This study examines the stratigraphic structure, paleoenvironmental development, and industrial viability of the Ağın diatomite deposits using comprehensive sedimentological, mineralogical, and geochemical investigations. Stratigraphic evidence indicates that the formation commenced with Early Miocene alluvial fan and shallow restricted marine sub-basin sedimentation prior to evolving into a significant marine incursion. This marine phase created a resilient carbonate platform structure consisting of reef-core, fore-reef, and back-reef sub-environments. Simultaneously, vigorous regional synsedimentary volcanism introduced high-flux silica pulses into the basin, acting as a major catalyst for diatom proliferation and high biological productivity within a restricted sub-basin setting. Geochemical analyses indicate that these bright white, diatomite deposits formed in conjunction with potassium-rich clays in a relatively deep, low-energy, and confined sub-basin of the Alibonca Sea. The high concentration of bulk SiO₂ and low trace element baselines are consistent with a high-purity deposional system and a low total rare earth element (ΣREE) abundance. However, their relatively high Al₂O₃ and K₂O contents indicate significant volcanic and terrigenous detrital input together with authigenic clay mineral formation during diatomite deposition, classifying the deposits as clay-bearing (argillaceous) diatomites rather than exceptionally pure diatomites. Chemical Index of Alteration (CIA) values indicate moderate continental chemical weathering under mostly hot and humid paleoclimatic conditions. The rapid terrestrial runoff and nutrient influx stimulated significant diatom growth before the ultimate late Early Miocene marine regression, transforming the area into a subaerial, volcanically influenced terrestrial environment. The Ağın deposits exemplify intra-platform marine silica sinks, demonstrating how tectonic–magmatic influences can surpass typical carbonate factory conditions to provide economically valuable biogenic mineral resources. Full article

The Alappuzha district in Kerala, India, has large deposits of high-grade silica sand, which is mainly used for glass manufacturing. The primary objective of the study is to map these mineral deposits using multispectral satellite data and machine learning algorithms (MLAs). Moreover, detailed geochemical and structural characterisation was performed using Energy-Dispersive X-ray Fluorescence (ED-XRF) and X-ray diffraction (XRD), which confirmed the characteristics of the silica sand, with a SiO₂ content of 96.93–99.13%. The laboratory proximal spectra in the range of 400–2500 nm were processed and compiled as a reference spectrum for mapping using Landsat and ASTER remote sensing datasets. The support vector machine (SVM) outperforms other algorithms with an overall accuracy of 97.82%. Integrating remote sensing techniques, mineral characterization, and field data facilitates eco-friendly, sustainable mining of these strategic minerals. Full article

Geothermal energy is a locally available, low-carbon resource that may support heat supply, building decarbonisation and regional energy diversification in non-volcanic crystalline settings. This study proposes an exploratory GIS-based approach for geothermal favourability mapping in the Guarda District, Central Portugal, where Hercynian granites, major fault systems and thermal and mineral water occurrences define a structurally controlled hydrogeothermal framework. Hydrogeochemical data from 54 groundwater abstraction points were integrated through silica-derived apparent geothermometric indicators, classical hydrothermal-parameter estimation and Empirical Bayesian Kriging Regression Prediction (EBKRP). Apparent silica-derived temperature indicators, circulation depth, geothermal gradient and theoretical thermal power were estimated, with log₁₀ transformed thermal power used as the dependent variable and distance to major mapped faults as the structural covariate. Apparent silica-derived temperature indicators range from 21.3 °C to 121.2 °C, with a mean of 64.6 °C, while estimated geothermal gradients range from 20.3 °C/km to 92.1 °C/km. Higher estimated values occur preferentially near NE–SW and NNW–SSE fault systems, suggesting that structural permeability may influence deep groundwater circulation. The interpretation explicitly acknowledges that, in low-temperature systems, dissolved silica may be influenced by chalcedony or amorphous silica control, as well as by cooling, mixing and incomplete re-equilibration during fluid ascent. The resulting map is interpreted as a screening-level favourability product, not as a definitive assessment of exploitable geothermal resources, and supports the prioritisation of future structural mapping, geophysical surveys, exploratory drilling, borehole temperature logging and applied geothermal assessment in fractured granitic terrains. Full article

The modification of cementitious binders using active mineral additives and nano-components represents a crucial pathway for developing high-performance, sustainable concrete composites. Nevertheless, unilateral modification of the matrix with highly reactive siliceous materials often leads to an undesirable increase in composite brittleness. This study investigates the synergistic effect of the concurrent application of nano-silica (NS), silica fume (SF), and Class F fly ash (FA) in ternary and quaternary binders, aimed at optimizing both load-bearing capacity and fracture toughness. The experimental program was conducted on seven concrete series, evaluating their mechanical parameters and non-linear fracture properties using the two-parameter fracture model (TPFM) on notched beams subjected to three-point bending. Additionally, a high-resolution energy partitioning framework was applied, decomposing the total fracture energy into four distinct components—fracture initiation energy in the elastic range (G_ini), pre-peak microcracking energy (G_pre), main material softening energy (G_soft), and residual tail energy dissipated at large crack openings (G_tail)—along with the determination of the characteristic length (l_ch). The results demonstrated that while purely siliceous systems (modified with NS and SF) generate high strength increments, they simultaneously trigger a “brittleness trap,” manifested by a 13.65% decrease in the l_ch parameter. The introduction of FA effectively mitigates this hazard, transforming the failure mode into a quasi-ductile behavior. The concrete series modified with the NS+FA hybrid (Mix-5) exhibited a spectacular 107% increase in G_f and an increase in l_ch of nearly 50%, while maintaining high fracture toughness. Energy decomposition analysis in quaternary concretes confirmed a desirable reduction in the initiation energy share in favor of the softening and tail phases (G_tail reaching a record 13.1% for Mix-7), suggesting the probable activation of macroscopic crack-bridging mechanisms driven by the delayed hydration of FA particles. The research indicates that precise design of multi-component binders allows for achieving an optimal technological equilibrium point—the “sweet spot”—combining high structural capacity with safe material ductility. Full article

The growing global consumption of concrete is driving up the demand for cement, which has a negative environmental impact due to intensive CO₂ emissions. This impact can be reduced by replacing cement with reactive mineral industrial waste, simultaneously addressing the issue of waste accumulation in landfills. However, to ensure the effective use of such materials, it is essential to comprehensively investigate their influence on concrete durability. This study analyzes glass processing waste (GPW) generated during glass grinding. The waste is removed using water, resulting in the formation of glass processing waste. In the experiment, CEM I 42.5 R cement, GPW, sand, crushed dolomite stone, concrete sludge (CS), chemical admixtures, and water were used. In the tests, cement was replaced with glass processing waste in amounts ranging from 5% to 30%, analyzing a total of seven different compositions. The properties of the sustainable concrete mixture were evaluated, and the mechanical–physical properties of the hardened concrete were determined. Resistance to alkali–silica reaction was tested according to the RILEM AAR-4 methodology, while the environmental impact of glass processing waste was assessed using Life Cycle Assessment (LCA). The results showed that glass processing waste increases the concrete’s resistance to alkali corrosion: as the amount of waste increased, a smaller change in the linear dimensions of the specimens was recorded, and the lowest mass loss was found in the composition where 20% of the cement was replaced by glass processing waste. The environmental impact assessment confirmed a direct correlation—as the amount of glass waste increases, CO₂ emissions decrease proportionally. To produce sustainable concrete, it is recommended to use up to 20% glass processing waste: this allows for the maximum reduction in environmental impact while maintaining mechanical properties and high resistance to alkali–silica reaction. Full article

Fresh flotation tailings represent an underutilized archive of mineralogical and geochemical information in which multiple strands of evidence for ore-forming processes and post-depositional modification can be preserved. Detailed characterization of tailings is also vital for assessment of their future potential as a secondary source of recoverable by-products. This study investigates residual mineral speciation and mineral distributions in size fractions of tailings from the Prominent Hill iron oxide–copper–gold (IOCG) deposit, South Australia, with emphasis on rare earth element (REE) minerals and associated phases containing uranium (U). Assemblages of REE minerals can be highly complex at the micron scale and include sequences of mineral replacement, notably monazite → florencite, and monazite → synchysite. Bastnäsite-(Ce) commonly appears paragenetically early and is frequently altered or replaced by synchysite and parisite, supporting episodes of REE remobilization and reconcentration over geological time. Uranium is closely associated with REEs, and U-mineral assemblages are similarly characterized by intricate replacement relationships between uraninite and secondary phases. Uraninite is variably replaced by coffinite and the U-carbonate wyartite, reflecting changes in redox state, silica activity, and fluid composition. Additional replacement pathways from uraninite to Cu–Fe sulphides, including bornite and chalcopyrite, are documented and indicate coupled dissolution–reprecipitation of sulphides and U-minerals during superimposed hydrothermal activity. Preservation of mineralogical relationships within tailings drawn from multiple parts of a large deposit highlights their value as an essentially untapped library of information to reconstruct deposit evolution, complementing traditional study of selected drill core samples. Systematic investigation of tailings from large deposits can improve genetic models for large copper deposits, including but not restricted to IOCGs, and provide essential insights into REE behaviour, uranium remobilization, and critical metal potential. These findings emphasize the scientific and economic value of tailings-based studies for improved resource characterization, refining metallogenic interpretations, guiding future exploration strategies, and assessing opportunities for reprocessing and metal recovery in large ore systems worldwide across diverse geological settings. Full article

Biomineralization in plant tissues is a widespread process accompanied by carbon fixation in biogenic minerals. This study aimed to evaluate the effect of CaCO₃ application to soil on the formation and localization of biominerals in the pericarp of fruits of Buglossoides arvensis (L.) I.M. Johnst., as well as on the accumulation of carbon in minerals. B. arvensis seeds were sown in the soil treated with CaCO₃ at concentrations of 0.0 (0 Ca), 2.5 (2.5 Ca), 5.0 (5 Ca), 7.5 (7.5 Ca), and 10.0 (10 Ca) t ha⁻¹. As a result of CaCO₃ application, on average across all treatments, the increase in soil pH was 30%, and the calcium and silicon content in the soil increased by 60 and 39%, respectively. The fruit weight was 4, 28, 42, and 21% higher in 2.5 Ca, 5 Ca, 7.5 Ca, and 10 Ca plants than in 0 Ca plants. Scanning electron microscopy analysis revealed the presence of silica and calcium carbonate in the pericarp of B. arvensis fruits, but showed no significant differences in the localization of biominerals in the pericarps between the treatments. The content of biosilica (phytoliths) was lower in 2.5 Ca, 5 Ca, 7.5 Ca, and 10 Ca plants than in 0 Ca plants, respectively, by 11, 14, 25, and 19%. The content of organic carbon occluded in a unit mass of phytoliths was, on average, 49% higher in treated than in 0 Ca plants. The content of carbonate fraction in fruits was 13, 14, 20, and 21% higher in 2.5 Ca, 5 Ca, 7.5 Ca, and 10 Ca plants than in 0 Ca plants, reflecting the effect of soil calcium levels on carbonate content in B. arvensis pericarp. Thus, in the pericarp of fruits, the ratio of silica to carbonates changed towards a decrease in silica content and an increase in carbonate content as the availability of calcium in the soil increased. In summary, B. arvensis responds to increased soil calcium and soil pH by increasing carbon accumulation in biominerals formed in fruit pericarps, supporting the potential for variability in plant biomineralization characteristics under changing growth conditions. Full article

The rapidly increasing global demand for high-performance thermal insulation materials necessitates a significant shift towards more sustainable and cost-effective solutions. This study unveils a novel and efficient pathway to synthesize engineered cordierite, a highly coveted magnesium aluminosilicate ceramic, by intelligently harnessing biogenic silica extracted directly from rice husk. Rice husk, an abundant agricultural by-product, represents a readily available and often underutilized resource. The methodology involved a precise precipitation method to successfully yield high-purity silica from rice husk ash. This extracted silica was then meticulously combined with commercial magnesium oxide (MgO) and aluminum oxide (Al₂O₃) through a solid-state reaction to synthesize the desired cordierite. The study systematically investigated the profound impact of various sintering temperatures, ranging from 850 °C to 1100 °C, on both the cordierite yield and its crucial physicochemical properties. Our experiments revealed that a sintering temperature of 1100 °C achieved a remarkable 66.5% cordierite yield. Beyond yield, the material processed at 1100 °C exhibited exceptional mechanical and thermal characteristics: a compressive strength of 65 kN/m², a flexural strength of 44 kN/m², a tensile strength of 17.5 kN/m², and a remarkably low thermal conductivity of just 3.2 W/m·K. These attributes match the mechanical requirements for structural insulation, with a thermal conductivity of 3.2 W/m·K. While higher than some high-porosity commercial cordierites (typically 1.2–2.0 W/m·K), the biogenic version offers a 40% reduction in production energy and utilizes 100% recycled silica, balancing thermal performance with superior sustainability. By utilizing agricultural waste, this method reduces CO₂ emissions associated with mineral extraction and minimizes reliance on non-renewable raw materials, providing a practical pathway for the circular economy. Full article

Calcium leaching increases the hydraulic concrete material’s porosity and the diffusion coefficient, thereby jeopardizing engineering safety. Fly ash and silica fume are commonly used mineral admixtures in hydraulic concrete, and their effects on the material’s leaching characteristics, especially its microstructural and transport properties, require further investigation. In this study, calcium leaching tests were conducted on cement paste (CP), silica fume–cement paste (SF), and fly ash–cement paste (FA) using a 6 mol/L ammonium chloride solution to accelerate the leaching process. Subsequently, a series of quantitative and qualitative analyses was performed on the deteriorated specimens, including phenolphthalein indicator spraying, X-ray diffraction (XRD), nuclear magnetic resonance (NMR), and scanning electron microscopy (SEM). Additionally, the diffusion coefficients of the material at different locations were calculated and analyzed. The results show that partially replacing cement with silica fume or fly ash increases the initial porosity, gel pore content, and initial diffusion coefficients. After 28 days of leaching, compared to the initial values, the porosity increases in the 0–4 mm layer from the leached surface were 83.6% for CP, 11.0% for SF, and 39.0% for FA. The diffusion coefficients increased by factors of 14.3 (CP), 6.1 (SF), and 13.6 (FA), indicating enhanced resistance to leaching. The primary reason for this is that the reactive silica in the admixtures undergoes a pozzolanic reaction with the calcium hydroxide generated by cement hydration, producing additional calcium silicate hydrate (C-S-H) gel, which reduces the capillary pores that would otherwise result from calcium hydroxide decomposition. Full article