Inorganic Composition Research Articles

Comprehensive Analysis of Elemental and Metabolite Composition in Boraginaceae Species From Türkiye.

Boraginaceae plants, including four endemic species from Türkiye, were analyzed for organic and inorganic compositions using inductively coupled plasma mass spectrometry (ICP-MS) and liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) to explore their nutritional, medicinal, and ecological significance. This study examined 18 species, identifying key elements, such as sodium (87 600.359-118 049.272g/kg), potassium (98 876.885-145 587.899g/kg), and iron (70 396.436-116 416.076g/kg), which showed significant variation. Metabolite profiling revealed the presence of alkaloids, flavonoids, and tannins in most samples. Additionally, 42 amino acids and 35 phenolic compounds were detected, with rosmarinic acid and proline being particularly abundant. Rosmarinic acid was most concentrated in Oi and Ml samples, whereas proline levels ranged from 3023.8086 to 7693.8549nmol/mL. The study highlights the intricate metabolic and elemental profiles of Boraginaceae species, shedding light on their ecological adaptations and therapeutic potentials. Spearman correlation analysis suggested significant relationships among phenolic compounds, amino acids, and elemental compositions, indicating potential applications in nutrition, pharmacology, and biodiversity conservation.

Aluminum and Inorganic Natural Pigment Colored Composites by Powder Metallurgy Forming

Aluminum powder, along with other powders such as steel or stainless steel, is extensively used in powder metallurgy (PM) to produce complex samples with irregular geometric shapes. PM enables the incorporation of fillers to modify the physical, mechanical, or wear properties of aluminum without melting, thereby preventing phase segregation. The novelty of this work lies in the use of inorganic natural pigments (INPs). The primary goal of this study is to produce colored aluminum samples via PM without compromising their mechanical properties. INPs are first characterized to select those with the highest heat resistance. The composites are fabricated with different pigments (10 wt%), formed through uniaxial compaction at 500 MPa, and sintered in a nitrogen atmosphere at 610 °C for 30 min. Density, color, bending strength, and wear are evaluated to identify the most suitable pigment for gas kitchen burners. Mars red, Cobalt blue, and Chrome green pigments provide the best coloration. Dimensional variation is generally less than 1%. The pigments increase the material’s brittleness by 41% to 77%, resulting in a bending modulus increase of up to 160% and deformation reduction of up to 70%. In some cases, intermetallic compounds improve bending strength, as in Al–Chrome green, by 30%. Al–Chrome green exhibits wear resistance comparable to aluminum, with a 40% lower friction coefficient. X-ray diffraction and SEM-EDX confirm AlCr and AlCo intermetallic particles. Thermal stability is verified after 160 heating and cooling cycles without significant material degradation.

Tailoring the photoluminescence of AIE-type gold nanoclusters via biomineralization-inspired polymorphism.

Tailoring the aggregation-induced emission (AIE) characteristics of well-defined metal nanoclusters (MNCs) is highly sought after for numerous practical applications. Studies have primarily focused on assembling AIE-type MNCs using monomorphic molecules. Achieving polymorphic assemblies, with different molecular arrangements could provide valuable insights into the role of external molecular matrices on the photoluminescence (PL) behaviour of these NCs. In this study, by mimicking biomineralization, we successfully embedded AIE-type Au22SG18 NCs within different polymorphic environments of CaCO3. Upon incorporation into CaCO3 matrices such as, calcite, vaterite and a mixture of both, the PL was enhanced in all the inorganic composites accompanied by a significant blue shift. In the metastable vaterite matrix, Au22SG18 NCs exhibited the highest blue shift in the PL spectrum while in the stable crystalline matrix of calcite, the NCs showed the highest PL intensity as well as excited state lifetime. Time-resolved spectroscopic and single-molecule Raman studies revealed that variations in the PL of NCs are linked to the stability of their polymorphic structures, progressing from vaterite to a vaterite/calcite mixture, and finally to calcite. These findings shed light on the crucial role of external molecular arrangement in the AIE behaviour of MNCs.

USING THE SECONDARY RAW MATERIALS OF GRAIN PROCESSING AND OIL SEED RECYCLING AIM TO INCREASE OIL REFINEMENT EFFICIENCY

In the article the expert analytical review of literature sources on the basis of set tasks on realization of the purpose of increasing the efficiency of safflower oil purification using secondary raw materials of grain and oilseed crops processing is carried out, the object of research and the purpose of technology of effective purification of safflower oil are defined. Methods of using secondary raw materials as filtering materials were analyzed, linen fiber is proposed as an optimal filtering material. Multifactorial experimental studies were carried out for the application of filtering material consisting of recycled processing raw materials in industrial equipment. We saw that when purification with filter media composed of recycled recycled processing raw materials, the safflower oil yield increased due to pump pressure. Under the influence of the pump pressure of 180-10-3 Pa, we can relate that the oil yield decreased and the capacity of the filter media decreased, and we can see that the safflower oil yield also increased due to the increase in filtration rate. As a result of filtering safflower oil through linseed fiber in a frame filter with a filtration rate of 0.1 L/s, the safflower oil yield increased to 93%. As a result of the study of fatty acid, inorganic composition and the amount of vitamens of safflower oil, we see a decrease in the content of saturated fatty acids and an increase in the content of mono- and polyunsaturated acids (oleic, behenic, cis-10-heptadecenoic and cis-linoleic acids), and we also observe that the inorganic composition meets all the norms, and the content of vitamin E increases.In the research work, frame filter press of FPR brand is used for purification of vegetable oil. As a result, the parametric dependencies of effective purification of safflower oil using filtering materials consisting of secondary raw materials of processing in a frame row filter press are substantiated and a rational solution for application in production is found.

Core-Shell Magnetic Particles: Tailored Synthesis and Applications.

Core-shell magnetic particles consisting of magnetic core and functional shells have aroused widespread attention in multidisciplinary fields spanning chemistry, materials science, physics, biomedicine, and bioengineering due to their distinctive magnetic properties, tunable interface features, and elaborately designed compositions. In recent decades, various surface engineering strategies have been developed to endow them desired properties (e.g., surface hydrophilicity, roughness, acidity, target recognition) for efficient applications in catalysis, optical modulation, environmental remediation, biomedicine, etc. Moreover, precise control over the shell structure features like thickness, porosity, crystallinity and compositions including metal oxides, carbon, silica, polymers, and metal-organic frameworks (MOFs) has been developed as the major method to exploit new functional materials. In this review, we highlight the synthesis methods, regulating strategies, interface engineering, and applications of core-shell magnetic particles over the past half-century. The fundamental methodologies for controllable synthesis of core-shell magnetic materials with diverse organic, inorganic, or hybrid compositions, surface morphology, and interface property are thoroughly elucidated and summarized. In addition, the influences of the synthesis conditions on the physicochemical properties (e.g., dispersibility, stability, stimulus-responsiveness, and surface functionality) are also discussed to provide constructive insight and guidelines for designing core-shell magnetic particles in specific applications. The brand-new concept of "core-shell assembly chemistry" holds great application potential in bioimaging, diagnosis, micro/nanorobots, and smart catalysis. Finally, the remaining challenges, future research directions and new applications for the core-shell magnetic particles are predicted and proposed.

Deep reinforcement learning for inverse inorganic materials design

A major obstacle to the realization of novel inorganic materials with desirable properties is efficient materials discovery over both the materials property and synthesis spaces. In this work, we propose and compare two novel reinforcement learning (RL) approaches to inverse inorganic oxide materials design to target promising compounds using specified property and synthesis objectives. Our models successfully learn chemical guidelines such as negative formation energy, charge neutrality, and electronegativity balance while maintaining high chemical diversity and uniqueness. We demonstrate multi-objective RL algorithms that can generate novel compounds with both desirable materials properties (band gap, formation energy, bulk modulus, shear modulus) and synthesis objectives (low sintering and calcination temperatures). We apply template-based crystal structure prediction to suggest feasible crystal structure matches for target inorganic compositions identified by our machine learning (ML) algorithms to highlight the plausibility of the identified target compositions. We analyze the benefits and drawbacks of the ML approaches tested in this work in the context of accelerated inorganic materials design. This work isolates and evaluates the effects of different RL methodologies to suggest promising, valid compounds of interest by exploring the chemical design space for materials discovery.

Innovative barnacle-inspired organic–inorganic hybrid magnesium oxychloride cement composites with exceptional mechanical strength and water resistance

Innovative barnacle-inspired organic–inorganic hybrid magnesium oxychloride cement composites with exceptional mechanical strength and water resistance

Inorganic Geochemistry of Coal from Patappa Village, Bone District, and Masenrengpulu Village, Barru District, South Sulawesi Province Using XRF Method

The chemical composition of coal is almost the same as that of plant tissue, containing the main elements of elements C, H, O, N, S, and P. An in-depth study of coal inorganic compounds is needed because coal inorganic compounds are the primary variable in ash formation during coal combustion. This study uses the X-ray fluorescence method to reveal the differences and similarities in inorganic chemical composition contained in coal in Bone Regency and Barru Regency. Coal in Masenrengpulu Village has the Al2O3 compound as the most dominant compound, while coal in Patappa Village has the SiO2 compound as the most prevalent compound. The concentration of inorganic sulfide minerals in the village of Masenrengpulu was influenced by igneous rock intrusion and deposition processes. In contrast, the deposition process only affected the inorganic sulfide minerals of coal in Patappa village. The significant elements found in coal in the Masenrengpulu and Patappa Villages are Si, Al, Fe, S, Ca, K, and Ti. Coal inorganic sulfide minerals in Masenrengpulu Village with Patappa Village have high concentrations in the bottom channel of the coal seam and a low concentration in the middle channel and top of the seam. Coal inorganic sulfide minerals in Masenrengpulu Village and Patappa Village have high concentrations in the coal seam's lower channel and low concentrations in the middle and upper channels. Keywords: Coal Comparison, Mallawa Formation, XRF, Inorganic Geochemistry.

Polyaniline@MoS2: An organic and inorganic hybrid framework for asymmetric supercapacitor applications

The polyaniline and MoS2-based organic and inorganic hybrid composite have been synthesized by varying MoS2 concentrations ranging from 1 to 10 wt% and their charge storage performances were analyzed in a three-electrode and in asymmetric cell configuration to understand their electrochemical characteristics. The electrochemical characteristics of the as-prepared electrodes such as cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy were studied in 1 M H2SO4 electrolyte. Among the prepared compositions PANI@MoS2 (5 wt%) electrode showed a high specific capacity of 148.6 F g−1 at 0.5 A g−1 among the prepared compositions. Further, the asymmetric hybrid pouch cell was fabricated where PANI@MoS2 and activated carbon were used as a positive and negative electrode, respectively. The 2 × 2 cm2 asymmetric cell (AC||PANI@MoS2(5 wt%) delivered a specific energy of 32 Wh kg−1 at a specific power of 3.2 kW kg−1 in the PVA-H2SO4 hydrogel electrolyte. This specific energy is two-fold higher than the AC||PANI asymmetric cell where the specific energy and specific power are about 18.66 Wh kg−1 and 3.2 kW kg−1, respectively. The cycle stability of the AC||PANI@MoS2 (5 wt%) was also performed at 2 A g−1 and the cell showed capacitance retention of about 99.27% after 13,000 cycles. The cell performances at different bending angles were analyzed to ensure the flexible nature of the pouch cell. Thus, the proposed organic and inorganic hybrid composite electrode is believed to be a potential electrode material for supercapacitor application in an acidic electrolyte medium.

A novel particle size distribution correction method based on image processing and deep learning for coal quality analysis using NIRS-XRF.

The combined application of near-infrared spectroscopy (NIRS) and X-ray fluorescence spectroscopy (XRF) has achieved remarkable results in coal quality analysis by leveraging NIRS's sensitivity to organic compounds and XRF's reliability for inorganic composition. However, variations in particle size distribution negatively affect the diffuse reflectance of NIRS and the fluorescence signal intensities of XRF, leading to decreased accuracy and repeatability in predictions. To address this issue, this study innovatively proposes a particle size correction method that integrates image processing and deep learning. The method first captures micro-images of the coal sample surface using a microscope camera and employs the Segment Anything Model (SAM) for binarization to represent particle size distribution. Subsequently, a Spatial Transformer Network (STN) is applied for geometric correction, followed by feature extraction using a Convolutional Neural Network (CNN) to establish a correlation model between particle size distribution and ash measurement errors. In experiments involving 56 coal samples, including 48at 0.2mm for the standard ash prediction model and 8 within a 0∼1mm range for correction, the results showed significant improvements: standard deviation (SD), mean absolute error (MAE), and root mean square error of prediction (RMSEP) decreased from 0.321%, 0.317%, and 0.335% to 0.229%, 0.225%, and 0.257%, respectively. Using the accuracy of the 0.2mm particle size validation set as a reference, compared to before correction, the errors in these metrics were reduced by 64.06%, 50%, and 60.80%, respectively. This study demonstrates that integrating deep learning and image analysis significantly enhances the repeatability and accuracy of NIRS-XRF measurements, effectively mitigating sub-millimeter particle size effects on spectral detection results and improving model adaptability. This method, through automated particle size distribution analysis and real-time result correction, holds promise for providing essential technical support for the development of online quality detection technologies for conveyor belt materials.

Aluminum alleviates iron deficiency chlorosis by interfering with phosphorus homeostasis in rice (Oryza sativa L.).

Rice (Oryza sativa L.) is a staple food for more than half of the human population. Rice plants are cultivated in several different environments, and face various abiotic stresses, including nutritional imbalance in soils. The ionome, the inorganic composition of an organism, is known to be tightly regulated, as changes in concentration of one element affect concentrations of others. Iron (Fe) is an essential element that is involved in redox reactions, nitrogen metabolism and chlorophyll synthesis. The hallmark of Fe deficiency in plants is leaf chlorosis, a phenotype known to be alleviated by deficiencies of other elements, such as phosphorus (P). Aluminum (Al) is abundant in soils and limits plant growth in acidic soils. Despite its well-established detrimental effects, Al has been proposed to have a positive effect on growth for some species, but little is known about this phenomenon. Here we aim to understand whether Al affects Fe homeostasis in rice. We found that Al alleviated Fe deficiency-induced chlorosis. +Al-Fe treatment decreased expression of Fe deficiency marker genes and partially recovered photosynthesis. We also observed that Al induced expression of a P deficiency marker gene, and addition of excess P to nutrient solution reversed effects of Al on chlorosis. Our data show that Al alleviates Fe deficiency-induced chlorosis, and suggests that this occurs indirectly by inducing P deficiency in leaves.

An Amphiphilic Molecule Induced Anion-Enrichment Interface for Next-Generation Lithium Metal Batteries.

The electrolyte engineering enables the fabrication of robust electrode/electrolyte interphase with excellent electrochemical stability for reliable lithium (Li) metal batteries (LMBs). Herein, an amphiphilic molecule nonafluoro-1-butanesulfonate (NFSA) is employed in electrolytes to realize anion-enrichment interfacial design. The functions of such an amphiphilic molecule in the electrolyte and anode/electrolyte interphases of LMBs are elucidated via theoretical and experimental analyses. The polar lithophilic segments (-SO3-) present a capability to solvate Li+, while the perfluoroalkyl chains (-CF2CF2CF2CF3) exhibit a solvent-phobic, which alters the Li+ solvation environment in the electrolyte and thus building a favorable interphase enriched with anion-derived inorganic compositions on Li electrode. As a result, the designed electrolyte enables stable operation of the Li||Cu cells for more than 200 cycles with a cumulative irreversible capacity loss of only 2.4 mAh cm-2, and the long-term cycle life of the Li||Li cells is extended to more than 1500h with a small overpotential (36.5mV). Moreover, prolonged cycle life of the full cell assembled with commercial LiFePO4 cathode (over 80% capacity retention after 500 cycles at 0.5 C) is achieved even under the limiting Li source (≈5 mAh cm-2), high cathode loading (≈12mg cm-2), and lean electrolyte (≈2.5µL mg-1).

Preliminary XRF Analysis of Coal Ash from Jurassic and Carboniferous Coals at Five Kazakh Mines: Industrial and Environmental Comparisons

This study analyzes 105 coal ash samples from Jurassic and Carboniferous coals from five mines in Kazakhstan, Lenin, Saradyr, Bogatyr, Maikuben, and Shubarkol, focusing on the inorganic elemental compositions, their occurrence, and industrial and environmental implications. Methods include coal ash yield and volatile matter analysis, mineralogical characterization via low-temperature ash X-ray diffraction (LTA-XRD), and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS). High-temperature ash (HTA) was analyzed using energy-dispersive X-ray fluorescence (EDXRF), highlighting XRF’s potential for rapid multi-elemental analysis. Nine major elements (Al, Si, P, S, Fe, K, Ca, and Ti) and eleven trace elements (As, Cu, Cr, Zn, Pb, V, Ga, Mn, Ni, Y, Yb, and Zr) were identified in HTA samples through EDXRF. SEM and dendrogram analysis confirm their co-occurrence with quartz, kaolinite, pyrite, and accessory minerals such as chalcopyrite, zircon, rutile, and REE-bearing apatite. The elemental content of samples enhances industrial suitability by reducing emissions. Only Yb shows slight enrichment for economic benefits, along with La, Ce, and Nd, while concentrations of potentially toxic elements indicate minimal environmental risk. EDXRF demonstrates its efficiency for large-scale investigations, with all samples analyzed in a few days using automated overnight measurements. This approach shows promise for future studies focusing on trace elements, including REE.

Calcium Carbonate as an Ionic Molecular Lock for Ultrastrong Fluorescence of Single Organic Molecules

AbstractLocking molecular conformation are widely applied in molecular engineering for improved performance. However, locking via organic functional groups often changes the original molecular properties. Following the rigidity and stability of ionic interaction in ionic compounds, we suggested the use of a molecular‐scale ionic compound, calcium carbonate oligomer, as a robust molecular segment to functionalize organic molecules. The rigid structure of the ionic molecular segments locked the organic molecules, which could remarkably limit the intramolecular motion and intermolecular interactions. This ensured a stable and ultrastrong fluorescence of the single organic molecule while preserving its original maximum emission wavelength. The locking strategy was general and extendable to multiple organic molecules. Additionally, the ultrastrong single‐molecular fluorescence can be maintained in inorganic solids with even higher quantum yields and almost unchanged maximum emission wavelength. The highest quantum yield of the investigated molecules reached 99.9 %, superior to all reported organic‐inorganic fluorescent composite under air conditions. This work demonstrates a general strategy to restrict intramolecular motion and intermolecular interactions by using ionic oligomers as molecular locks, providing an alternative method for realizing ultraemissive molecules. This further demonstrates a fascinating example of molecular engineering in the presence of inorganic ionic molecules.

Calcium Carbonate as an Ionic Molecular Lock for Ultrastrong Fluorescence of Single Organic Molecules.

Locking molecular conformation are widely applied in molecular engineering for improved performance. However, locking via organic functional groups often changes the original molecular properties. Following the rigidity and stability of ionic interaction in ionic compounds, we suggested the use of a molecular-scale ionic compound, calcium carbonate oligomer, as a robust molecular segment to functionalize organic molecules. The rigid structure of the ionic molecular segments locked the organic molecules, which could remarkably limit the intramolecular motion and intermolecular interactions. This ensured a stable and ultrastrong fluorescence of the single organic molecule while preserving its original maximum emission wavelength. The locking strategy was general and extendable to multiple organic molecules. Additionally, the ultrastrong single-molecular fluorescence can be maintained in inorganic solids with even higher quantum yields and almost unchanged maximum emission wavelength. The highest quantum yield of the investigated molecules reached 99.9 %, superior to all reported organic-inorganic fluorescent composite under air conditions. This work demonstrates a general strategy to restrict intramolecular motion and intermolecular interactions by using ionic oligomers as molecular locks, providing an alternative method for realizing ultraemissive molecules. This further demonstrates a fascinating example of molecular engineering in the presence of inorganic ionic molecules.

Enhancing High‐Voltage LNMO Cathode Performance in Li‐Metal Batteries Via Anionic Electrolyte Additive‐Integrated CEI Engineering

AbstractAn anionic‐additive electrolyte system is introduced by incorporating Lithium tetrafluoroborate (LiBF4) into a conventional base electrolyte for high‐voltage LiNi₀.₅Mn₁.₅O₄ (LNMO) cathodes in lithium‐metal batteries. At high voltages, the sacrificial oxidation of LiBF4 mitigates electrolyte degradation and forms a robust cathode electrolyte interface (CEI) enriched with boron and fluorine‐based components, which protects against active material corrosion. Density Functional Theory (DFT) studies reveal that BF₄⁻ is more readily oxidized, while MD simulations validate the CEI's inorganic composition. Initial cycling with a specialized charge‐discharge protocol ensures optimal use of the additive, resulting in a uniform, thin (4–6 nm) CEI on the LNMO cathode. The CEI formed in anionic‐additive electrolyte system effectively suppresses transition metal dissolution and surface degradation, enhancing long‐term cycling performance. The LiBF4‐enhanced electrolyte also lowers overpotential and promotes more uniform Li deposition compared to the base electrolyte. At a 1 C‐rate, the LNMO cathode with a Li metal anode and optimized electrolyte achieves a discharge capacity of 115 mA h g⁻¹ and an energy density of 540 Wh kg⁻¹ over 500 cycles. These findings underscore LiBF4’s dual role in protecting LNMO cathodes and Li metal anodes, highlighting the critical role of additives in CEI development for advanced lithium‐metal batteries.

Chitosan as a Templating Agent of Calcium Phosphate Crystalline Phases in Biomimetic Mineralization: Theoretical and Experimental Studies.

Highlighting the essential role of chitosan (CS), known for its biocompatibility, biodegradability, and ability to promote cell adhesion and proliferation, this study explores its utility in modulating the biomimetic mineralization of calcium phosphate (CaP). This approach holds promise for developing biomaterials suitable for bone regeneration. However, the interactions between the CS surface and in situ precipitated CaP still require further exploration. In the theoretical section, molecular dynamics (MD) simulations demonstrate that, at an appropriate pH level during the prenucleation stage, calcium ions (Ca2+) and hydrogen phosphate ions (HPO42-) form Posner-like clusters. Additionally, the interaction between these clusters and the CS molecule enhances system stability. Together, these phenomena facilitate the transition to subsequent heterogeneous nucleation on the surface of the organic matrix, which is a more controlled process than homogeneous nucleation in solution. Dynamic simulation results suggest that CS acts as a stabilizing matrix at pH 8.0 during biomimetic mineralization. In the experimental section, the effects of pH and the molecular weight of CS were investigated, with a focus on their impact on the crystal structure of the resulting material. X-ray diffraction and scanning electron microscopy analyses reveal that, under conditions of approximately pH 8.0 and a CS molecular weight of 20 000 g/mol, and controlled ion concentration, ultrasound radiation, and temperature, the dominant CaP phases in the material are carbonate-doped hydroxyapatite (CHA) and octacalcium phosphate (OCP). These findings suggest that CS, when adjusted for molecular weight and pH, facilitates the formation of CaP crystal phases that closely resemble the natural inorganic composition of bone, highlighting its protective and regulatory roles in the growth and maturation of crystals during mineralization. The theoretical predictions and experimental outcomes confirm the crucial role of CS as a templating agent, enabling the development of a biomimetic mineralization pathway. CS's ability to guide this process may prove valuable in the design of materials for bone tissue engineering, particularly in developing effective materials for bone tissue healing and regeneration.

Effect of inorganic salt composition on strength, microstructure and leaching toxicity of coal-based solid waste backfill materials

This study explores the potential of coal-fired slag, desulfurized gypsum and modified magnesium slag as cementing agents for coal-based solid waste backfill materials. Inorganic salts like CaCl2, Na2SO4 and Na2SiO3 were used as excitants to investigate their combined impact on the mechanical properties, microstructure and leaching risk of hazardous elements from the coal-based solid waste backfill materials. The findings show that the addition of inorganic salt boosts the alkalinity within the liquid-phase reaction system. This disrupted the hydration-blocking membrane, accelerating the dissolution and reaction rate of the silica-alumina mineral components within the cementitious material. Concurrently, the inorganic salt ions consumed the early alkaline hydration products, destroying the hydration reaction equilibrium and facilitating the formation of hydration products like AFt, C-S-H gel, C-A-S-H gel, and Friedel's salt. This increase in the solid-phase volume content and microscopic densities in the reaction system improved the early mechanical properties of the coal-based solid waste backfill materials. Additionally, after a 28-day curing period, the leaching concentration of deleterious elements in the coal-based solid waste backfill material containing inorganic salt components was below the permissible concentration limit of the Class III groundwater quality standard. This eco-friendly backfill material is promising for mine backfilling, a potential substitute for traditional cement-based backfill material.

Fracture behavior of brittle particulate composites consisting of a glass matrix and glass or ceramic particles with elastic property mismatch

The aim of this work is two-fold: i) elaborating dense and transparent inorganic glass composites with improved fracture properties, and ii) testing the theoretical analysis proposed in [1] and based on Poisson's ratio mismatch. Particulate composites, consisting of glass or ceramic particles embedded in a soda-lime-silica glass matrix, were synthesized and their fracture behavior was studied by means of the Single-Edge Precraked Beam (SEPB) and Double Cleavage Drilled Compression (DCDC) methods, using in situ experiments with X-ray tomography where possible. An important effect of the T-stress on the fracture toughness (KIc) was observed in the case of DCDC experiments. KIc is increased by about 40 % by incorporating 7 vol. % amorphous silica beads or SrAl2O4:Eu,Dy ceramic particles (SAED) with a 40 μm mean particle size. It is suggested that toughening results from the crack front trapping and pinning at particle sites and from the tortuous crack path in the case of a-SiO2 particles, and from the contribution of the intrinsic fracture surface energy of the ceramic particles, which are cleaved by the propagating crack, in the case of the SAED particles. The thermally induced stress field is believed to play a major role in the case of a-SiO2 particles. Two glass grades possessing Young's moduli similar to the one of the matrix but much larger Poisson's ratios were used to produce glass beads. However, the incorporation of these latter beads in the matrix was found to have a minor incidence on the fracture behavior.

Inorganic composition of PM2.5 in the lower northern region of Thailand and their potential impact on human health

Inorganic composition of PM2.5 in the lower northern region of Thailand and their potential impact on human health