Decoding ancient mortars: complementary strengths of SR-μXRPD and FPA-FTIR in high-resolution binder analysis.

Lithium aluminum silicate (LAS) glass-ceramics materials are promising or under investigation in the field of dental restorations, but are not currently the most widely used due to their aesthetic performance. However, their materials often exhibit lower hardness under intensive contact conditions compared to alternative prosthetic crown systems. This study aims to determine an optimal temperature–time schedule for the nucleation and crystallization processes of Li–Al–Si glass, as well as clarify the correlation between translucency and surface hardness .The heat treatment protocol was designed based on differential thermal analysis (DTA) results and established thermal protocols. Nucleation was performed at a fixed temperature of 520°C for durations ranging from 0 to 60 minutes. Crystallization stages were conducted at 750°C and 900°C to evaluate the impact of crystal density (nucleation) and crystal growth (crystallization) on the materials properties. Vickers hardness (HV) was measured, with the highest value (~7.66 GPa) observed in samples treated at 750°C. The results indicate that optimal translucency (HTP) is achieved through a fine, homogeneously distributed crystalline phase, whereas uncontrolled crystal growth at higher temperatures leads to a decrease in the translucency parameter (TP), increasing opacity.

Preparation of red mud-based polyferric silicate aluminum flocculant via response surface optimization and evaluation of its performance in turbidity and fluoride ion removal.

Cesium adsorption on a TiO2 channel in a thin-film transistor (TFT) is examined to improve channel conductivity. The TFT consists of a 16 nm-thick anatase TiO2 channel, Ti source and drain electrodes, and an SiO2 gate capacitor. The gate width and length are 1 mm and 60 μm, respectively. The cesium adsorption is performed by immersing the TFT in a CsCl solution. Before immersion, the TiO2 channel is covered with periodically stacked layers of aluminum silicate and SiO2, which effectively adsorb cesium ions in the CsCl solution. We also assume that the Cs absorbed multiple layers act as a Cs diffusion source to the TiO2 channel layer. The doping of Cs is investigated by x-ray photoelectron spectroscopy. The pristine TFT without the Cs adsorption exhibits a carrier mobility of ∼0.54 cm2/V s with drain currents around 30 μA and a gate voltage of 20 V. After the immersion of the TFT in a 0.1mM CsCl solution, the drain current increases to the milliampere range. An equivalent-circuit model and COMSOL-device simulator suggest enhanced effective mobilities exceeding ∼90 cm2/V s. These results suggest that Cs diffuses into the TiO2 channel and suppresses oxygen-vacancy traps, thereby leading to the high electron mobility. The operation mechanism of the Cs-adsorbed TiO2 TFT and its applicability are discussed in this paper.

This study systematically investigates the effect of electrolytes with varying silicate–aluminate ratios on the microstructure, phase composition, coating thickness, and surface roughness of aluminum coatings synthesized via the PEO process on pure Al. The coatings primarily consist of mullite (Al6Si2O13), ɣ-Al2O3 and α-Al2O3 phases. Increasing the aluminate content promoted α-Al2O3 formation and a higher number of smaller discharge channels, while higher silicate content favored mullite formation. Coating thickness increased with higher silicate concentrations, whereas surface roughness remained relatively constant across different electrolyte compositions.

ABSTRACT Amid growing environmental concerns and the search for sustainable building materials, this study investigated the mechanical and microstructural behavior of clay‐based mortars reinforced with coconut fibers. Mixtures were produced in which natural sand was replaced by sand and clay residues, with fiber additions of 2.5% and 5% by weight of cement. The mortars were evaluated in fresh and hardened states, compressive and flexural strengths, and through scanning electron microscopy (SEM), energy dispersive x‐ray spectroscopy (EDS), and x‐ray diffraction (XRD) analyses. The clay residue produced compressive strength values comparable to the reference mixture. The incorporation of 5% coconut fibers resulted in a statistically significant increase in flexural strength compared to the non‐reinforced mortar, despite the formation of shrinkage‐induced microcracks. The analysis confirmed the presence of quartz, kaolinite, orthoclase, and calcium aluminum silicate. The results highlight the potential for applying waste and natural fibers in eco‐efficient mortars, emphasizing the importance of curing and moisture control.

Potassium and Aluminum Silicate Application to Alleviate the Adverse Effects of Heat Stress on ‘Hass’ and ‘Red’ Avocado Trees

The mechanical properties of 3D-printed dental resin materials are critical for their clinical success. Unfilled resin materials used in 3D printing for dental applications often exhibit reduced biaxial flexural strengths (BFSs) due to differences in material composition and printing processes. This article aims to evaluate and compare the BFS and fractographic characteristics of SLA-printed unfilled resin (UR) and composite (C) materials, and to identify factors influencing their mechanical properties.Two experimental groups were fabricated: an unfilled resin group (URG) and a leucite-reinforced composite group (CG; 35 wt% filler). The filler percentage is in an attempt to explore the possibility of slightly surpassing an already 3D printed 30 wt% ceramic composite concentrate-resin. Disc-shaped specimens (n = 20 per group) were printed using SLA and post-cured according to the manufacturer's recommendations. BFS was measured using the ball-on-ring test. Weibull analysis and scanning electron microscopy (SEM) were used to assess strength reliability and fracture features. X-ray diffraction (XRD) was used to confirm the crystalline phase of the leucite filler against International Centre for Diffraction Data (ICDD) standards. One-way ANOVA and Tukey's multiple comparisons were conducted after confirming data normality and homogeneity of variances at p < 0.05.XRD analysis confirmed the presence of tetragonal potassium aluminum silicate (leucite) phase, aligning with ICDD reference codes. The mean BFS of the URG (228.83 MPa) was significantly higher than that of the CG (91.62 MPa). The URG exhibited brittle fracture with various hackle markings and minimal phase delamination, indicative of high flexibility and energy absorption due to increased TEGDMA ratio. The CG showed lower BFS values, with fractographic features such as porosities, minor filler particle agglomeration, and phase delamination due to settling filler particles. SEM images revealed a homogeneous distribution of filler particles in CG but also showed micro-cracks and voids that compromised its mechanical integrity. Weibull analysis revealed a higher Weibull modulus for URG (10.26) compared with CG (5.48), indicating more consistent mechanical performance.The URG showed significantly higher BFS than the CG, likely due to greater elastic deformation and energy absorption from its higher TEGDMA content. In contrast, the CG's lower BFS was linked to porosity and filler particle settling during printing. SEM analysis revealed challenges in achieving uniform filler distribution and adequate curing. Future studies should focus on optimizing filler properties, conversion rates, and incorporating nanofillers to enhance the flexural strength of 3D-printed dental composites.

This study aims to characterize the minerals in rock samples from Dembek and Wariab Villages, South Manokwari Regency, West Papua, using the X-ray Diffraction (XRD) method. XRD was used to identify crystalline phases and mineral compositions in the rocks, as well as to understand the geological conditions and mineral resource potential in the area. Rock samples were systematically collected from both locations and analyzed using an X-ray diffractometer. The analysis results show that the rocks from Dembek Village are dominated by quartz (SiO 2 ), Sodium Aluminum Silicate (Na 1.45 Al 1.45 Si 0.55 O 4 ), Potassium Aluminum Silicate (KAlSi 2 O 6 and KAlSiO 4 ), Potassium Silicon Fluoride (K 2 SiF 6 ), Albite (Na (Si 3 Al)O 8 ), Magnesium (Mg), Sodium Magnesium Aluminum Silicate (Na 3 MgAlSi 2 O 8 ), and Potassium Magnesium Silicate (K 2 MgSi 5 O 12 ). The rocks from Wariab Village contain a more varied range of minerals from two sampling points, namely, at the WRB-L1 location, consisting of halite (NaCl), quartz (SiO 2 ), Potassium Magnesium Fluoride (KMgF 3 ), Potassium Magnesium Silicate (K 2 MgSi 5 O 12 ), anorthite (CaAl 2 Si 2 O 8 ), and Potassium Aluminum Silicate (KAlSi 2 O 6 ). The WRB-L2 location consisted of fluorite (CaF 2 ), Potassium Silicon Fluoride (K 2 S1F 6 ), sylvite (KCl), sodalite (Na 4 Al 3 Si 3 O 12 Cl), and Sodium Aluminum Silicate (Na 1.65 Al 1.65 Si 0.35 O 4 ). These differences in mineral composition reflect variations in the formation environment and geochemical processes that occur at each location.

The use of waste concrete powder (WCP) in geopolymer synthesis offers a sustainable method for recycling construction and demolition waste (CDW). However, its low reactivity and high calcium content frequently result in geopolymers with inadequate mechanical strength. To overcome this challenge, this study proposes a novel method that involves the synergistic addition of metakaolin (MK) to improve the performance of WCP‐based geopolymers. The study systematically examines the effects of NaOH concentration (6, 10, 14 M) and MK content (0%–100%) on the unconfined compressive strength (UCS), microstructure, and reaction products. The findings indicate that the inclusion of MK significantly improves the UCS. An optimal blend of 75% MK and 25% WCP, activated by a 14 M NaOH solution, achieves a peak strength of 46.84 MPa, which is considerably higher than that of geopolymers made from either precursor independently. Microstructural analyses (X‐ray diffraction [XRD], scanning electron microscopy/energy‐dispersive X‐ray spectroscopy [SEM/EDS], and Fourier‐transform infrared spectroscopy [FTIR]) confirm that the strength improvement is due to the formation of a denser and more uniform matrix. This is characterized by the cohesive coexistence of sodium aluminosilicate hydrate (N–A–S–H) gel from MK and calcium (aluminate) silicate hydrate (C–A–S–H) gel from WCP. The innovation of this study lies in demonstrating the effective synergy between a highly reactive aluminosilicate source (MK) and a low‐reactivity waste material (WCP), transforming a potential performance inhibitor (calcium) into a strength‐enhancing element. This study presents a practical and efficient strategy for converting waste concrete into valuable geopolymer materials, offering significant environmental advantages and fostering sustainable development within the construction sector.

The effects of yttrium (Y) addition on the formation of inclusions in 0.5C-1Cr-0.2Mo-0.1V spring steel were studied via thermodynamic calculations and scanning electron microscope (SEM) coupled with energy dispersive spectrum (EDS). According to thermodynamic calculations of Gibbs free energy, [Y] reacts with [O] and [S] but not with [C] in molten steel, with Y 2 O 2 S and Y 2 O 3 being more easily formed inclusions in steel at 1873 K than YS and Y 2 S 3 when the Y content is less than 0.06%. The experimental results show that the inclusions in spring steel without Y addition are mainly large irregular aluminum silicate, Al 2 O 3 -SiO 2 -TiO 2 and MnS inclusions. The addition of 0.011% Y can eliminate large inclusions and form square Y 2 O 3 and complex Y 2 O 3 -Y 2 O 2 S inclusions with Y 2 O 2 S in the core and surrounding Y 2 O 3 . When the Y content increased to 0.019%, the size of Y 2 O 3 decreased, and isolated spherical Y 2 O 2 S formed. The addition of 0.031% Y can further decrease the size of Y 2 O 2 S, and Y 2 O 3 is replaced by YS. A good consistency was observed between the calculated result of the Gibbs free energy and the experimental result. Moreover, a three-dimensional stability diagram of precipitation under equilibrium conditions at 1873 K is established to predict the formation sequence of Y-containing inclusions with different Y contents. The formation sequences are Y 2 O 2 S → Y 2 O 3 with Y contents in the range of 0.01−0.02%, YS → Y 2 O 2 S → Y 2 O 3 with Y contents in the range of 0.02−0.06% and Y 2 S 3 → YS → Y 2 O 2 S → Y 2 O 3 with Y contents in the range of 0.06−0.08%.

Dimethyl Ether (DME) is a clean, colorless gas that serves as a potential alternative to liquefied petroleum gas (LPG). This study presents a comprehensive techno-economic assessment of DME production via methanol dehydration with a plant capacity of 20,000 tons per year. The process utilizes an alumina–silicate catalyst in a multitube fixed-bed reactor operating at 300–350°C and 30 bar. Simulation results show a methanol conversion of 85% per pass, achieving a final DME purity exceeding 99.5%. The total capital investment (CAPEX) is estimated at USD 12.8 million, with annual operating costs (OPEX) of approximately USD 13 million. Economic indicators reveal a Net Present Value (NPV) of USD 5.2 million, an Internal Rate of Return (IRR) of 14.5%, a Return on Investment (ROI) between 15–17%, and a payback period of six years. The break-even point (BEP) is reached at 60–65% of design capacity. The findings indicate that the DME production process is technically feasible and economically attractive for industrial implementation, supporting Indonesia’s clean energy transition and reduction of LPG imports.

Calcium magnesium phosphate cements (CMPCs) were obtained starting from dolomite (alone or mixed with fly ash) thermally treated at two different temperatures. Dolomite calcination at 750 °C for 3 h determined the formation of a mixture of MgO and CaCO3. The mixing of dolomite with fly ash and the increase in the calcination temperature at 1200 °C determined the formation of new compounds (calcium aluminum silicate and calcium magnesium silicates), which are present along with MgO and small amounts of CaO in the thermally treated material. These two precursors were mixed with KH2PO4 solution and borax (as a retardant admixture) to obtain the CMPCs. The setting time and compressive strengths of these CMPCs were assessed and the XRD analyses provided insights into their mineralogical composition after hardening and thermal treatment. The cements, as so or mixed with perlite, were applied on steel plates, to assess their behavior when put in direct contact with a flame. The compatibility of these materials with the steel substrate was evaluated by scanning electron microscopy (SEM). The direct contact with the flame up to 60 min provided information regarding the CMPCs’ ability to prevent the rapid increase in the substrate (steel plate) temperature. The findings indicate that CMPC pastes and composites containing perlite can offer a degree of protection for steel structures in the event of a fire.

This study presents a method for purifying acidic aluminum chloride solutions, specifically targeting the removal of iron (Fe) impurities to enhance the quality of alumina produced from aluminum silicate clay. The research employed solvent extraction using di(2-ethylhexyl)phosphoric acid (D2EHPA) dissolved in kerosene as the extracting agent. The investigation was conducted using both simulated solutions and actual leach solutions derived from hydrochloric acid processing of clay ore. Key experimental parameters included reaction time, organic-to-aqueous phase ratio (O/A), and the concentrations of HCl, D2EHPA, iron, aluminum, potassium, and sodium. The results demonstrated that the efficiency of iron extraction improved significantly with increased concentrations of both HCl and the D2EHPA extractant. However, the presence of excessive chloride ions was found to have a negative impact on this efficiency. Analysis using a McCabe-Thiele diagram indicated that a high iron removal rate exceeding 91% necessitates a two-stage extraction process. The study identified optimal conditions for this purification: a mixing time of 30 minutes, a D2EHPA concentration of 20%, and an equal organic-to-aqueous phase ratio (O/A = 1:1). Under these precise conditions, the process achieved a remarkable iron removal efficiency of 95.58%, demonstrating its high effectiveness for this specific application.

Abstract A low thermal conductivity, compatible thermal expansion coefficient, and excellent resistance to calcium–magnesium–aluminum–silicate (CMAS) corrosion are critical requirements for thermal/environmental barrier coatings (T/EBC) applied to silicon‐based ceramics. Rare earth disilicates are considered among the most promising ecological barrier coating materials due to their superior resistance to water vapor corrosion. However, the relatively high thermal conductivity and poor resistance to CMAS corrosion limit the practical application. In this work, a single‐phase high‐entropy rare earth disilicate (Lu 1/5 Yb 1/5 Sc 1/5 Er 1/5 Y 1/5 ) 2 Si 2 O 7 ((5RE 1/5 ) 2 Si 2 O 7 ) was successfully synthesized via a solid‐state reaction. It exhibits a low thermal conductivity of 1.92 W⋅m −1 ⋅K −1 at 1273 K, a thermal expansion coefficient (4.89 × 10 −6 /°C) matching that of SiC f /SiC ((4.5–5.5) ×10 −6 /°C), high hardness and elastic modulus (11.22 and 184.6 GPa, respectively, at 25°C), and exceptional CMAS corrosion resistance, forming a reaction layer of only 28 µm after 48 h at 1300°C. The enhanced comprehensive performance is attributed to the synergistic combination of multiple rare‐earth cations with different ionic radii within the high‐entropy structure, highlighting its great promise as a next‐generation T/EBC material.

Corrosion of steel structures remains a persistent challenge in construction, particularly in coastal and industrial environments where chloride-induced degradation accelerates structural failure. This study presents an eco-friendly approach to improve the corrosion protection of the steel by incorporating Lawsonia inermis (henna) leaf extract into zinc–aluminum silicate coatings. The henna extract was added at varying concentrations (0–12 wt%) to evaluate its influence on structure, adhesion, and electrochemical performance of the coating. Physicochemical characterizations including FTIR, XRD, XRF, and SEM revealed that a 5 wt% addition optimized pigment dispersion, resulting in a denser and more homogeneous coating microstructure. Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization tests after 35 days of immersion in 3.5 wt% NaCl solution demonstrated that this formulation achieved the highest impedance and polarization resistance, confirming enhanced corrosion resistance. The improvement was attributed to the dual action of the henna extract: (i) as a dispersant, promoting uniform Zn–Al pigment distribution and reducing porosity, and (ii) as a green corrosion inhibitor, forming an adsorbed protective film on the steel surface. This work highlights the potential of bio-derived additives to enhance the long-term durability of steel infrastructure and supports the development of sustainable protective materials for construction applications.

To address the issue of restricted grout diffusion caused by seepage effects during grouting in sandy soil layers, this study proposes an optimised grouting method for water-based polyurethane-cement composite grout (WPU-CS) under vacuum-pressure synergy. By establishing a porous medium flow model based on the mass conservation equation and linear filtration law, the influence mechanism of cement particle seepage effects was quantitatively characterised. An orthogonal test (L9(34)) optimised the grout composition, determining the optimal parameter combination as the following: water-to-cement ratio 1.5:1, polyurethane-to-cement ratio 5~10%, magnesium aluminium silicate content 1%, and hydroxypropyl methylcellulose content 0.15%. Vacuum permeation grouting tests demonstrated that compared to pure cement slurry, WPU-CS reduced filter cake thickness by 80%, significantly suppressing the leaching effect (the volume fraction δ of cement particles exhibited exponential decay with increasing distance r from the grouting end, and the slurry front velocity gradually decreased). Concurrently, the porosity ϕ in the grouted zone showed a gradient distribution (with more pronounced porosity reduction near the grouting end). When vacuum pressure increased from -10 kPa to -30 kPa, slurry diffusion distance rose from 11 cm to 18 cm (63.6% increase). When grouting pressure increased from 20 kPa to 60 kPa, diffusion distance increased from 8 cm to 20 cm (150% increase). The study confirms that synergistic control using WPU-CS with moderate grouting pressure and high vacuum effectively balances seepage suppression and soil stability, providing an innovative solution for efficient sandy soil reinforcement.

Mullite whisker and aluminum silicate fiber co-reinforced silica composite aerogel with excellent mechanical properties and high temperature resistance by combustion technology

Illite, a prevalent clay mineral found in hydrated bauxite ore, decreases the aluminum-to-silicon ratio (Al < 7) while inducing competitive crystallization between sodium and potassium during the leaching process, thereby reducing the leaching efficiency of aluminum oxide. Consequently, illite-type bauxite ores are typically subjected to desiliconization prior to undergoing Bayer process leaching. However, this conventional desiliconization exhibits limited efficacy in illite removal and requires further refinement. To overcome these limitations, this study proposes the 'calcification-potassium alkali'(CPA) process, which substitutes KOH for NaOH in a simulated Bayer process targeting illite. This strategy alleviates sodium-potassium competition and facilitates the complete utilization of elements to synthesize potassium aluminosilicate. Furthermore, calcium oxide is partially incorporated to purify the mother liquor. Experimental investigations were conducted to evaluate leaching performance under varying conditions, leading to the determination of optimal parameters: a temperature of 280°C, a calcium-silicon ratio of 0.2, a liquid-solid ratio of 5:1, a K2O concentration of 200g/L, and a reaction duration of 60min. Under these conditions, the illite conversion rate reached 98.65%, with the effective K₂O and SiO2 contents in the product measured at 21.73% and 27.17%, corresponding to 89.38% and 86.54% of the total K2O and SiO2, respectively. Moreover, these parameters satisfy the national standards for organic-inorganic compound fertilizers, enabling subsequent production of mineral potassium-silicon fertilizers. Further leaching experiments on illite-type hydrated bauxite demonstrated efficient aluminum extraction, achieving a leaching rate of 73.82%, while effecting a phase transformation of the aluminum-silicon mineral from hydrated sodium aluminum silicate (Na2O·Al2O3·1.7SiO2·nH2O), typical of the traditional Bayer process, to potassium aluminum silicate (K2O·Al2O3·SiO2). This transformation can be utilized to prepare mineral potassium silicate fertilizers, which supply essential nutrients to plants and promote environmentally sustainable practices within both metallurgical and agricultural industries.

The viability of converting recycled concrete fines (RCF) into low-grade artificial limestone, through carbonation in aqueous systems, for use as a sustainable replacement for high-grade limestone in limestone–calcined clay cement (LC3) was explored. The experimental results suggest that the carbonated RCF (CRCF) exhibited high pozzolanic activity, generating additional calcium (aluminium) silicate hydrate (C-(A)-S-H) to serve as nucleation sites for LC3 hydration. The refined particle size of the CRCF and the presence of fine-sized calcium carbonate further facilitated initial ions dissolution, accelerating early-age hydration and improving the pore structure of the LC3. Moreover, the incorporation of CRCF significantly enhanced the compressive strength of the LC3. Specially, when CRCF were used as a complete replacement of limestone, the compressive strength improved by 19.82% at 3 days and 2.50% at 28 days, respectively, relative to the control. These findings demonstrate the potential of CRCF as a sustainable alternative to limestone, contributing to both efficient concrete waste utilisation and environmentally friendly LC3 production.