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Thanks to their exceptional thermal and electrical properties, borosilicate glasses are widely used in chip packaging and electronic pastes. Nonetheless, borosilicate glass powders suffer from the phenomenon of foaming and expansion during sintering process, which greatly affects the sintering densities of the powders and poses limitations to their applications. Herein, we explored the foaming mechanism of borosilicate glasses by ball milling. The foaming of borosilicate glass is due to the adsorption of CO 2 from the atmosphere by the glass powder during ball milling. The CO 2 forms carbonates on the surface of the glass powder and is released during the sintering process, leading to foaming. Additionally, as the specific surface area of the glass powder increases, its corrosion resistance decreases while its foaming strength increases. The foaming strength of the four glass powders, listed in ascending order, is: SrO-B 2 O 3 -SiO 2, ZnO-B 2 O 3 -SiO 2 , BaO-B 2 O 3 -SiO 2 and CaO-B 2 O 3 -SiO 2. Meanwhile, it was found that the foaming strength could be weakened better by ball milling organic modification method. These findings contribute to a deeper understanding of the glass foaming phenomenon. Furthermore, they offer practical strategies to reduce the foaming and optimize the performance of borosilicate glass-based materials in applications of chip packaging and electronic pastes. [ABSTRACT FROM AUTHOR]

In this work, a new type of high-entropy ceramic powder (La 0.2 Ce 0.2 Gd 0.2 Er 0.2 Sm 0.2) 2 Zr 2 O 7 was synthesized by sol-gel method and high-temperature sintering (1000 °C) method. Combing (La 0.2 Ce 0.2 Gd 0.2 Er 0.2 Sm 0.2) 2 Zr 2 O 7 and glass powder to prepare high-entropy ceramic-glass composite coating. The composite coating exhibits excellent seawater corrosion resistance and high-temperature resistance performance. The impedance values of composite coating are 2.36 × 106 Ω cm2 in 3.5 % NaCl solution for 24 h. The high-entropy ceramic-glass composite coating could withstand the high temperature of 600 °C for 30 days and remains tight and intact with stainless steel without falling out. This work shows that the (La 0.2 Ce 0.2 Gd 0.2 Er 0.2 Sm 0.2) 2 Zr 2 O 7 -glass composite coating can provide long-term high-temperature and seawater corrosion protection for stainless steel and has good application prospects in the field of marine corrosion protection. [ABSTRACT FROM AUTHOR]

In this paper, SiO 2 -P 2 O 5 -Ca(Sr/Zn)O-Na 2 O-F system glasses with varying CaO:SrO and CaO:ZnO ratios were prepared by traditional melting method, which combined the remineralization properties of bioglass with the special functions of Zn2+ and Sr2+. The evolution of glass composition and its thermal properties, network structure, and biological properties was investigated by DSC, FTIR, and biological experiment. The results showed that all the extracts of glass powder could promote the osteogenic differentiation of human periodontal ligament cells (HPDLCs). Among them, the two kinds of glass containing 6 wt% SrO and only 2 wt% ZnO had the greatest potential to accelerate the bone tissue reconstruction. Hematoxylin-eosin (HE) staining histological results showed that 3 months after the two kinds of glass were implanted in the animal model of periapical inflammation, the bone matrix formed a good seal in the apical foramen, and new bone and capillaries were formed in the apical area, which has a clinical application and transformation prospect. [ABSTRACT FROM AUTHOR]

To cope with the cross-sensitivity of simultaneous measurement of ultraviolet (UV) irradiance and temperature, we propose and experimentally demonstrate a miniature composite photoluminescent probe that is formed by thoroughly mixing Er/Yb co-doped tellurite glass powder into a resin adhesive substrate. Utilizing tellurite glass in form of powder not only guarantees its thorough mixing into the liquid resin base, but also retains its amorphous glass phase for hosting Er/Yb ions, thus breaking the limitations of studying tellurite glass only in bulk or fibrous form. Co-excited by UV radiation and NIR pumping, the composite probe produces a superimposed fluorescence emission spectrum, where the intensity change rate of the 488 nm dip can be used for UV irradiance measurement, and the fluorescence intensity ratio (FIR) of the 524 nm and 545 nm peaks for temperature measurement. Based on the sensitive specificity of the resin substrate and the Er/Yb co-doped tellurite glass, we have realized the simultaneous measurement of UV and temperature without cross-sensitivity. [ABSTRACT FROM AUTHOR]

Geopolymers represent a distinct class of materials characterised by their X-ray amorphous nature and nanoporous, nanoparticulate structure. Geopolymers can be conveniently mixed, poured, and cured under ambient conditions. This makes this class of materials an interesting alternative to ordinary Portland cement for structural processes. Additionally, the addition of alumina can improve mechanical properties, while the addition of glass can form an impermeable glaze which could be useful for molten salt containment. Therefore, in this investigation, potassium metakaolin-based geopolymer composites with varying proportions of glass particles and alumina platelets were fabricated, cured, heat-treated, and analyzed to study the effects of composition on material properties. Various attributes including rheological properties, densities, mass loss, shrinkage, and porosities were compared. It was observed that certain compositions exhibited high viscosities, making high shear mixing challenging, while also displaying significant permeability that would hinder their ability to contain liquids without leakage. Additionally, certain samples showed reduced densities, suggesting potentially weaker mechanical properties; however, the investigation did not include a direct assessment of mechanical properties. The most promising candidates for containing liquids at high temperature contained 50 wt% KGP, 25 or 35 wt% glass powder, and 25 or 15 wt% alumina platelets, respectively. ASH-G slurries required a minimum of 65 vol% KGP to produce a homogenous material compatible with additive manufacturing. The minimum amount of glass phase to form surface glazes was 16 vol%. Only samples containing more glass phase than alumina phase produced glazed composites. [ABSTRACT FROM AUTHOR]

Polymer–ceramic composites are widely used in refractory cables. The ceramic fillers provide high temperature and fire resistance, while the polymer matrix provides flexibility and improved electrical insulation. The properties of the polymer–ceramic composites are determined by the ceramization‐forming properties of the corresponding ceramifying powders. Properties such as shrinkage, density, and porosity were characterized to compare the effects of different contents of glass powder. The sintering activation energy was calculated using the logarithmic relationship between shrinkage and holding time. The microstructure, cross‐section, and crystalline phases were investigated by scanning electron microscopy (SEM) and X‐ray diffraction analysis (XRD) to explore the ceramization process of sericite ceramifying powder. The ceramization process of ceramifying powder is proposed. The results show that during low‐temperature sintering, the glass powder and muscovite phases melt and partially transform into α‐quartz and albite low during cooling down. [ABSTRACT FROM AUTHOR]

Quartz glass powder is a type of silicon-rich industrial waste. Accumulation of this waste has led to resource wastage and environmental pollution. In this paper, quartz glass powder is used as raw material for preparing xonotlite through hydrothermal synthesis. The effects of Ca/Si (C/S) molar ratio, liquid/solid ratio, reaction temperature, and reaction time on the conversion of quartz are studied. The phase and structural changes of glass powder are analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Based on this, the conversion mechanism of quartz in glass powder is explained. The dissolution rate of quartz in an alkaline solution is a critical factor that restricts hydrothermal reactions. The conversion rate of quartz can be effectively increased by raising reaction temperature and extending reaction time. When the reaction temperature is 240 °C and the reaction time reaches 14 h, the conversion of quartz can reach 94.5 wt%. This study reveals the conversion mechanism of quartz in hydrothermal reactions and provides a theoretical basis for the efficient utilization of glass powder. [ABSTRACT FROM AUTHOR]

This article aims to investigate the mechanical properties and substrate adhesion of the pull-off method in polymer mortars modified with styrene-butadiene resin polymer (SBR) containing glass powder and composite fiber-reinforced slag. Different mix designs were investigated with and without SBR, taking into account different amounts of glass powder and slag separately and in combination, along with the effect of glass, polypropylene, and steel fibers alone and in combination. The flexural performance and energy absorption of beams retrieved with these layers were also assessed. The results revealed significant differences and increases in the substrate adhesion of the restored modified polymer layers containing SBR compared to the polymer-free repair overlays. Furthermore, an improvement was observed in the adhesion performance of the repair overlay using a combination of slag and glass powder and the glass and polypropylene fiber composite. The highest adhesion was related to the modified polymer mortar design containing composite fibers of glass, polypropylene, and steel with 25% replacement of SBR polymer for 10% glass powder, 10% slag, and 5% slag with 5% glass powder. The adhesion was increased by about 3.74, 3.72, and 3.78 times compared to the repair overlay of the control design. Modified polymer mortars had a higher T 150 D toughness. Moreover, the energy absorption was significantly improved by the presence of SBR polymer. The highest toughness values were found in the beams restored with modified polymer mortars containing polypropylene, glass, and steel composite fibers with an increase of 48.51%-66.42% compared to the samples without polymer as a result of the pozzolans used in this mix. [ABSTRACT FROM AUTHOR]

The aim of the study is to evaluate the ability of cathode-ray tube funnel waste glasses (CRT-F) to shield photons (gamma and X-ray) and other forms of radiation with rest masses (i.e., neutrons and charged particles) after their Pb content was reclaimed. The lead (Pb) content of cathode-ray tube funnel waste glasses (CRT-F) was reduced using Na 2 CO 3 as the reducing agent CRT-F(Na 2 CO 3). CRT-F and CRT-F(Na 2 CO 3) were produced using the melt and quench processes using the powder of pristine funnel glass from discarded cathode ray tube glass and the reduced glass powder, respectively, as the starting materials. The X-ray fluorescence technique was adopted for determining the chemical composition of CRT-F and CRT-F(Na 2 CO 3) glasses. The parameters relating to the gamma photon, fissile neutron, moderated neutron, slow neutron, and charged radiation (β, H+, He2+, and C6+) attenuation abilities of pristine CRT-F and CRT-F(Na 2 CO 3) were evaluated. The FLUKA simulation code and XCOM were used to estimate the mass attenuation coefficient of the glasses. The stopping power (S p) and range (R) of β, H+, and He2+ were evaluated by using the NIST data-based calculators (ESTAR for β, PSTAR for H+, and ASTAR for He2+) while S p and R data for C6+ was determined using SRIM. The cross section for fast, thermal (25 meV), and slow neutrons (0.1–10 meV) was also estimated. The Pb reclamation from the CRT-F drastically increased the half value layer of photons by at least a factor of 4 at 0.1 MeV and by more than 90 % at 10 MeV. The CRT-F interacts more with fissile and thermal neutrons compared to CRT-F(Na 2 CO 3). Although, CRT-F showed a better ability to attenuate all the radiation types considered, both glasses are better absorbers of radiation (especially photons) than some common shields. The reduction of Pb weight in CRT-F resulted in a drastic reduction in the ability of the glass to attenuate radiation; the resulting glass (CRT-F(Na 2 CO 3)) is however, an environmentally safer glass shield. [ABSTRACT FROM AUTHOR]

This study investigated the mechanical and microstructural properties of lightweight aggregate geo-polymer concrete (LWAGC) produced by alkali-activating glass powder (GP) and Fly Ash (FA) at elevated temperatures ranging from 200 to 800°C. It also examined the effects of incorporating crushed foam masonry (RFA) and crushed porcelanite rock aggregates (PA) into FA and GP-based geo-polymer concrete, both before and after exposure to ambient and high temperatures. A low-calcium type of FA was used as a binder in the geo-polymer concrete paste, with a 10 % replacement of glass powder. The concrete samples were heated at temperatures of 200°C, 400°C, 550°C, and 800°C for a duration of 60 minutes, with a heating rate of 7°C per minute. It was observed that the inclusion of weaker coarse aggregate resulted in a reduction of the compressive strength of the concrete. The geo-polymer concrete was subjected to tests for water absorption, mass loss, cracking, and microstructure analysis at elevated temperatures. The findings indicate that at heating temperatures of 400°C and above, the geo-polymer concrete underwent degradation and dehydration. The test findings also revealed residual compressive strengths of 104.9 %, 97.2 %, 81.8 %, and 64.2 % for the (RFA) types, and 107.3 %, 94.8 %, 78.3 %, and 58.8 % for the (PA) types. Additionally, the density decreased by 1.02 %, 4.88 %, 8.10 %, and 13.88 % for (RFA) and (PA) types, respectively, and by 0.27 %, 1.91 %, 4.67 %, and 10.79 % overall. The results indicate that the compressive strength of the concretes increased after exposure to elevated temperatures of 35°C and 200°C. However, when exposed to temperatures ranging from 400°C to 800°C, the strength of the LWAGC started to degrade and decline. Based on the obtained findings, the present study recommends performing laboratory tests on construction waste generated during demolition while developing and evaluating numerical models that predict the behavior of the resulting demolition materials when incorporated in the production of geo-polymer concrete. [ABSTRACT FROM AUTHOR]

Preparing electrospun fibers by applying a potential difference between a polymeric solution and a contacting substrate is increasingly attracting attention in tissue engineering applications. Among the numerous polymers, polycaprolactone (PCL) bioscaffold has been widely investigated due to its biocompatibility and biodegradability. Bioactive powder can be added to further improve its performance. In the present study, bioactive glass powder modified by adding 0–6 wt.% antibacterial zinc element (coded as ZBG) was prepared through the sol–gel process. Furthermore, PCL bioscaffolds with various ZBG additions were prepared using the electrospinning technique. The zinc-doped bioactive glass powder and electrospun PCL/ZBG bioscaffolds were evaluated using scanning electron microscopy, X-ray diffraction and Fourier-transform infrared spectroscopy to determine their structural properties. Additionally, in vitro bioactivity, biocompatibility and antibacterial performance were investigated. Experimental results showed that sol–gelled ZBG powder possessed superior bioactivity and 0.8 g ZBG was the optimal addition to prepare PCL/ZBG bioscaffolds with. All the electrospun PCL/ZBG bioscaffolds were biocompatible and their antibacterial performance against two S. aureus strains (SA133 and Newman) improved with increasing zinc concentration. Electrospun PCL/ZBG bioscaffolds exhibited excellent bioactivity and have great potential for biomedical application. [ABSTRACT FROM AUTHOR]

Ultra‐high‐performance cementitious composite (UHPCC) incurs higher economic costs and resource wastage due to its high cement/silica fume (SF) content. The paper aims to achieve sustainability and environmental friendliness of UHPCC by substituting cement/SF with glass powder (GP). The influence of various GP particle sizes and substitution levels on the mechanical properties of UHPCC was investigated. X‐ray diffraction and scanning electron microscopy were employed to analyze the impact of GP on the hydration process of UHPCC from a microscopic perspective. In addition, the internal damage pattern of GP‐UHPCC was simulated by the RFPA3D program. The results show that the addition of GP could achieve superior fluidity than GP‐0. Compared to conventional UHPCC, GP‐20 exhibits improved strength, initial flexural toughness, and residual flexural toughness. Furthermore, finer GP particle sizes contribute to enhanced matrix strength and flexural energy absorption capacity to some extent. Additionally, the incorporation of 5%–20% GP leads to an increase in the characteristic peaks of hydrated lime and C‐S‐H gel, which are beneficial to improving the internal microstructure of the matrix. Based on the RFPA3D program, the crack area, principal stress distribution, and acoustic emission energy of specimens with 15%–25% GP substitution levels were significantly higher than those of specimens with low substitution levels (0%–10%). Generally speaking, a GP substitution level of 15%–25% is found the most effective range for improving strength, and toughness behavior in this study. [ABSTRACT FROM AUTHOR]

This research investigates reinforced concrete beams with three groups of Glass Fiber Reinforced Polymer (GFRP) bar, Sand-blasted Glass Fiber Reinforced Polymer (SGFRP) bar and steel bar with concrete containing recycled materials with different concrete mix design before and after applying elevated temperature. The concrete mix designs include replacing glass powder and micro-silica with a part of concrete cement and replacing waste crumb rubber and glass crumb with a part of fine and coarse concrete aggregate. The beams were subjected to high temperature up to 600 °C in an electric furnace, and then subjected to the flexural strength test. The results showed that applying elevated temperature to beams reinforced with composite bars caused a sharp drop in flexural strength. The beam exposed to high temperature containing glass powder, coarse rubber and micro-silica had 2.2 times more flexural strength than the reference beam exposed to high temperature, and the beam not exposed to high temperature in this mix had 36% more flexural strength and 54% more ductility than the reference beam that was not exposed to high temperature. The beam with SGFRP bar with sand coating showed higher flexural strength after applying elevated temperature than the beam with GFRP bar with normal surface. In general, the replacement of recycled materials in the concrete improved the performance of the beams against elevated temperature compared to the beams with normal concrete. [ABSTRACT FROM AUTHOR]

The utilization of waste from various sources plays an important role in minimizing environmental pollution and civil construction costs. In this research, the mechanical properties of concrete were studied by mixing electronic waste (EW), glass powder (GW), and ceramic tile waste (CW). The effects of weight percentages of EW, GW, and CW are considered to investigate improvements in mechanical properties such as compressive strength (CS), split tensile strength (STS), and flexural strength (FS) of concrete. Taguchi analysis has been applied to predict the optimum composition of waste mixing percentages. The Multi-Objective Optimization Ratio Analysis (MOORA) techniques are applied to estimate the optimum composition of mixing wastes for maximizing the CS, STS, and FS of concrete. It was observed that 10 wt.% of EW, 15 wt.% of GW, and 30 wt.% of CW are predicted as the optimal mixing combinations to obtain a maximum compressive strength of 48.763 MPa, a split tensile strength of 4.178 MPa, and a flexural strength of 7.737 MPa, respectively. Finally, the predicted optimum waste-mixed weight percentages were used to examine the microstructure and various elements in the concrete using SEM and XRD analysis. When compared to conventional concrete, the optimum waste-mixed concrete has improved its compressive strength (38.453%), split tensile strength (41.149%), and flexural strength (36.215%). [ABSTRACT FROM AUTHOR]

We present a hollow cylindrical three-dimensional nonlinear photonic crystal for annular beam shaping. By inducing a modification with the near-infrared femtosecond laser inside lithium niobate, we experimentally achieve second-order nonlinear optical coefficient modulation in three dimensions. The center dark spot ratio of the generated annular beam can be adjusted by varying the hollow ratio of the cylindrical structure. To demonstrate the controlled linear variation of the annular distribution, we generate annular beams with center dark spot ratios ranging from 0 to 0.7. Furthermore, we illustrate the feasibility of the generated annular beam in optical trapping by manipulating glass powder particles with diameters of 4–10 μm in water. Our hollow cylindrical structure owns effective control of beam dark spot ratio, while providing a tool for generating annular beam. [ABSTRACT FROM AUTHOR]

Waste materials contribute to a wide range of environmental and economic problems. To minimize their effects, a safe strategy for reducing such negative impact is required. Recycling and reusing waste materials have proved to be effective measures in this respect. In this study, an eco-friendly treatment is investigated based on using waste powdered glass (WGP) and EPS beads (EPSb) as mechanical and chemical admixers in soils. For this purpose, Atterberg limit, standard proctor, free swell, and unconfined compression tests are performed on soil samples with different ratios of waste materials at their optimum moisture contents. The obtained test results indicate that adding WGP to cohesive soils increases the unconfined compressive strength (UCS) and reduces free swell (FS). In contrast, using EPSb reduces both FS and UCS of the treated soil samples. An optimum combination of both waste materials is determined for the improvement of the properties of high plasticity clay used in this study. Furthermore, multiple linear regression (MLR) and artificial neural network (ANN) methods are used to predict the FS and UCS of the clayey soils based on the data obtained here and the experimental test results reported in the literature. Once the FS and UCS values of untreated soil and additive percentages are defined as independent variables, both methods are shown to predict the FS and UCS values of the treated soil samples on a satisfactory level with the coefficient of correlation ( R 2 ) values greater than 0.926. Additionally, when only the index properties (liquid limit, plastic limit, and plasticity index) of the soil samples with waste materials are used as dependent variables, the R 2 values obtained by the ANN method are 0.968 and 0.974 for FS and UCS, respectively. The results of the untreated soil samples' FS and UCS tests are known, and the linear regression and ANN techniques yield similar results. Lastly, the ANN method is used to predict the FS and UCS of the treated samples in accordance to the limited predictors (e.g., only the Atterberg limits of the soil sample). [ABSTRACT FROM AUTHOR]

Bioactive glasses are renowned for their applications in dentistry, serving as restorative materials, dental adhesives, intracanal medicaments, and agents for enamel remineralization. Niobium pentoxide (Nb 2 O 5) is employed in dental adhesive resins and orthodontic adhesives, offering radio-pacifying properties essential for dental materials. Samarium oxide (Sm 2 O 3) emerges as a potential additive in aesthetic restorative dental ceramics and resins, enhancing the natural fluorescence of teeth. In this study Nb 2 O 5 and Sm 2 O 3 -doped (1, 3, and 5 wt%) 13–93 bioactive glass particles were synthesized via the sol-gel method, tailored for dental implementations. We conducted a comprehensive analysis of the physical, structural, and optical properties of the resultant glass powders. Additionally, their in vitro bioactivity and ionizing radiation shielding characteristics were rigorously evaluated. The results indicate that Sm3+ ions preserve the amorphous nature of the silicate glasses, while Nb5+ incorporation leads to the crystallization of the T-Nb 2 O 5 phase. Bioactivity assays across three physiological fluids—simulated body fluid, α-minimum essential medium, and phosphate-buffered saline, demonstrated the ability of doped glasses to facilitate hydroxyapatite layer formation, with the most pronounced bioactivity observed in phosphate-buffered saline immersed samples. Furthermore, radiation shielding simulations reveal that the addition of Nb 2 O 5 and Sm 2 O 3 enhances the ionizing radiation attenuation capabilities of the glasses, a property that holds significant promise for protecting against radiation in dental radiology. It can be concluded that the dual functionality of Nb5+ and Sm3+-doped bioactive glasses, which may revolutionize restorative dental practices and offer improved protection in radiological applications. [ABSTRACT FROM AUTHOR]

This research investigates the potential of using nanoparticles, Poly Aluminum Silicate and Poly Calcium Silicate, and industrial by-products, Recycled Glass Powder (RGP) and Ground Granulated Ballast Furnace Slag (GGBS) to enhance the durability and strength of a sandy soil, particularly in wet or saturated conditions where water table is close to building foundations. The study aims to determine the optimal content and concentration of additives and assess their influence on the compressive strength and the failure strain. The optimal content and concentration of dry additives and alkaline solutions were determined. Uniaxial compressive strength tests were conducted on various stabilized geopolymers, considering factors such as alkaline activator type, nanoparticle type and percentage, and degree of saturation. Scanning electron microscopy images were taken and analyzed to verify geomechanical testing outcomes. Mixtures with nanomaterials exhibited greater strength than untreated soil, with some exhibiting up to a tenfold increase. GGBS-based samples displayed a twofold increase in strength with nanomaterial addition, while RGP-based samples experienced reduced strength. However, both nanomaterials addressed the durability concerns in wet conditions. The addition of 2% nanomaterials to GGBS-based mixtures led to significant strength gains, with some showing a 20% increase after saturation. This research indicated the potential of nanoparticles and industrial by-products in resolving a major concern regarding geopolymers which is the lack of durability in wet or saturated conditions. These findings have implications for eco-friendly geoconstruction materials and practices. [ABSTRACT FROM AUTHOR]

The complex interactions between soil and additives such as lignin, glass powder, and rubber tires were investigated using principles of material and soil mechanics. Previous research has mainly focused on individual additives in clay soils. In contrast, this study investigates soil improvement with two different types of waste materials simultaneously. The improvement of soil properties by hybrid waste materials was evaluated using several laboratory tests, including the standard Proctor test, the unconfined compressive strength test, the California Bearing Ratio (CBR) test, and cyclic triaxial tests. The aim of this research is to identify key parameters for the design and construction of road pavements and to demonstrate that improving the subgrade with hybrid waste materials contributes significantly to the sustainability of road construction. The mechanical and physical properties were evaluated in detail to determine the optimal mixtures. The results show that the most effective mixture for the combination of waste glass powder and rubber tires contains 20% glass powder and 3% rubber tires, based on the dry weight of the soil. For the combination of waste glass powder and lignin, the optimum mixture consists of 15% glass powder and 15% lignin, based on the dry weight of the soil. These results provide valuable insights into the sustainable use of waste materials for soil stabilization in road construction projects. [ABSTRACT FROM AUTHOR]

Recent research has focused on assessing the effectiveness of response surface methodology (RSM), a non-machine learning technique, and artificial neural networks (ANN), a machine learning approach, for predicting concrete performance. This research aims to predict and simulate the compressive strength of concrete that replaces cement and fine aggregate with waste materials such as eggshell powder (ESP) and waste glass powder (WGP) for sustainable construction materials. In order to ensure concrete's durability and structural integrity, a compressive strength evaluation is essential. Precise predictions maximize efficiency and advance sustainability, particularly when dealing with waste materials like ESP and WGP. The response surface methodology (RSM) and artificial neural network (ANN) techniques are used to accomplish this for practical applications in the built environment. A dataset comprising previously published research was used to assess ANN and RSM's predictive and generalization abilities. To model and improve the model, ANN used seven independent variables, while three variables, cement, waste glass powder, and eggshell powder, improved the RSM. Both the ANN and RSM techniques are effective instruments for predicting compressive strength, according to the statistical results, which include mean squared error (MSE), determination coefficient (R2), and adjusted coefficient (R2 adj). RSM was able to achieve the R2 by 0.8729 and 0.7532 for compressive strength, while the accuracy of the results for ANN was 0.907 and 0.956 for compressive strength. Moreover, the correlation between ANN and RSM models and experimental data is high. The artificial neural network model, however, exhibits superior accuracy. [ABSTRACT FROM AUTHOR]

Rigid polyurethane foam (RPUF) is a common filling material for tunnels surrounding rock in China. The Chinese national standard explicitly stipulates that RPUF, utilized as a tunnel filling material, must adhere to the following criteria: a thermal conductivity of ≤0.1 W/(m·K), a compressive strength of ≥150 kPa, a limiting oxygen index of ≥26%, and a flame-retardant grade of B2. However, the flame-retardant grade B2 is still possible to burn in the special environment of the tunnel. In view of the strict requirements of national standards for thermal conductivity, compressive strength, and flame-retardant performance of RPUF, this study focuses on optimizing the comprehensive performance of RPUF through scientific matching of flame retardants. The aim is to prepare RPUF that not only meets the national standard but also can reach B1 level. Three flame retardants, melamine polyphosphate (MPP), expandable graphite (EG), and low melting point glass powder (LGP), were selected for the ratio test. Measurement correlation coefficient. A comprehensive analysis of these test results was conducted. The results show that: When the overall proportion of EG-MPP-LGP is 41% and EG:MPP:LGP = 26:13:2. Its thermal conductivity is 0.0555 W/(m·K), compressive strength is 216.72 kPa, and the limiting oxygen index is 32.2%, which increases by 74% compared with pure RPUF. The flame-retardant grade achieved is B1, categorizing it as a flame-retardant material. Additionally, all other properties measured align with national standards. This innovative preparation method provides material support for tunnel safety engineering and has practical value. [ABSTRACT FROM AUTHOR]

Additive manufacturing presents promising potential as a sustainable processing technology, notably through integrating post-consumer recycled polymers into production. This study investigated the recycling of high-density polyethylene (rHDPE) into 3D printing filament, achieved by the following optimal extrusion parameters: 180 °C temperature, 7 rpm speed, and 10% glass powder addition. The properties of the developed rHDPE filament were compared with those of commonly used FDM filaments such as acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) to benchmark the performance of rHDPE against well-established materials in the 3D printing industry, providing a practical perspective for potential users. The resulting filament boasted an average tensile strength of 25.52 MPa, slightly exceeding ABS (25.41 MPa) and comparable to PLA (28.55 MPa). Despite diameter fluctuations, the filament proved usable in 3D printing. Mechanical tests compared the rHPDE filament 3D printed objects with ABS and PLA, showing lower strength but exceptional ductility and flexibility, along with superior sound absorption. A life cycle analysis underscored the sustainability advantages of rHDPE, reducing environmental impact compared to conventional disposal methods. While rHDPE falls behind in mechanical strength against virgin filaments, its unique attributes and sustainability position it as a valuable option for 3D printing, showcasing recycled materials' potential in sustainable innovation. [ABSTRACT FROM AUTHOR]

The pressureless sintering process is essential to densify near net shaped parts with good shape fidelity. In this work, the impact of the particle size distribution and crystallization state on the processing and properties of final sintered multicomponent lithium disilicate (SiO 2 -Li 2 O-K 2 O-P 2 O 5 -Al 2 O 3 -ZnO) was evaluated. Higher densification was achieved by pressureless sintering at lower temperatures for samples prepared with fine glass-based powders (825 °C; ≈96%) rather than coarse crystallized powders (975 °C; 92.9%). However, samples based on fine powders presented a microstructure characterized by low aspect ratio crystals, while those based on coarse powders presented needle-like crystals with high aspect ratio. Best mechanical properties were found in samples prepared with coarse glass powders (relative density≈ 95.1%; Vickers Hardness≈ 5.2 GPa; indentation fracture toughness≈ 2 MPam0.5; flexural strength≈ 317 MPa) sintered at 875 °C-1 h. These results can provide valuable orientations for the post-processing of lithium disilicate glass-ceramics prepared by additive manufacturing techniques. [ABSTRACT FROM AUTHOR]

To improve the heat extraction efficiency from the wellbore fluids to the stratum in the geothermal well, thermal insulation cement, which contains of waste glass powder as a heat-insulating material, is proposed to apply in geothermal well's middle and upper sections in the paper. Effect of such glass powers on mechanic and thermal property of thermal insulation cement was then investigated. Various tests were carried out to measure compressive strength, thermal conductivity, microstructure porosity etc. parameters of the thermal insulation cement. Results showed that the waste glass powder would enhance its the compressive strength and improve its the thermal insulation performance. Correlation study between contents of the added waste glass powder in geothermal cements and its mechanic and thermal property was conducted. It was found that thermal insulation cement exhibited its optimum performance when the added content of glass powers was 20% in weight. Analysis of the microstructure porosity with SEM found that the pores in thermal insulation cement with added waste glass powders were mostly closed, tiny and even, and therefore contributed to the compressive strength of the thermal insulation cement; such pores would be also beneficial to improving its thermal insulation performance. [ABSTRACT FROM AUTHOR]

This study investigates the tribological properties of resin composites reinforced with the fillers of glass powder and micro-bubbles. Resin composites were prepared with varying concentrations from 1% to 5% wt of fillers. Tribological tests were conducted using a block-on-ring scheme under dry friction conditions. The measurements of friction coefficient and wear values were performed under variable rotation speeds and loading conditions. The study showed that resin composites with 2–3% glass powder fillers and resin composites with 3–4% micro-bubbles exhibited optimal tribological properties. The resin glass powder modifications reduce the wear by 63% and resin micro-bubbles reduce wear by 32%. SEM analysis of the surfaces revealed surface imperfections and structural damage mechanisms, including abrasive and fatigue wear. The study concludes that specific filler concentrations improve the friction and wear resistance of resin composites, highlighting the importance of material preparation and surface quality in tribological performance. The increased wear resistance on both composites would hopefully expand the usage of additive manufactured composite, namely industrial moving components such as polymer gear, wheel, pulley, etc. [ABSTRACT FROM AUTHOR]

Soil improvement is a significant aspect of geotechnical engineering that requires periodic assessment and modification. This study aims to see how glass powder (GP) and rubber particles (RP) affect the shear strength and bearing capacity of clay soil collectively and separately. The soil samples were subjected to direct shear testing and California Bearing Ratio (CBR) tests at various glass powder and rubber particle contents. The CBR test was conducted under soaked and unsoaked conditions. Clay-rubber, clay-glass powder, and clay-rubber-glass powder mixtures were prepared for the tests. It was discovered that adding glass powder and rubber particles improved the soil's shear strength parameters and bearing capacity. A comparative analysis was conducted on the clay-rubber mixtures and clay-glass powder mixtures. The results indicated much improvement by the rubber particles than the waste glass powder in the direct shear test. In contrast, the glass powder had a better impact than the rubber particles in the CBR test. Furthermore, a correlation analysis was conducted to ascertain the relationship between the CBR values and the shear strength of the soil samples using a single Linear Regression Analysis (SRLA) model. The correlation yielded satisfactory coefficients (R2), indicating a strong link between the engineering properties. [ABSTRACT FROM AUTHOR]

Colourless glass particles are found in oil painting layers from the fifteenth-seventeenth centuries. Several historical sources mention the use of finely ground glass powder as a solid drier. In order to assess the siccative effect of glass particles added to paint, this research focused on red lake reconstructions and followed their natural drying using Fourier transform infrared (FTIR) analysis. Three glasses with different sodium-potassium and manganese contents were studied. Significant differences in drying rates were observed in each of the samples, indicating a relationship between both the composition – either enriched with or without manganese – and the size of the glass particles added as siccatives. This FTIR approach highlights several complex mechanisms involved in the drying effect of glass powders mixed in paint layers. [ABSTRACT FROM AUTHOR]

The present study is dedicated to the manufacturing of highly porous triply periodic minimal surface (TPMS) constructs, fabricated from recycled end of life borosilicate pharmaceutical glass employing masked stereolithography. The structures were prepared from a simple blend of photocurable resin with glass powder (<38 µm). The gyroid model was selected with the porosity varying from 75 to 90%. Hot stage microscopy was applied to examine the glass sintering behaviour to improve the translucency of the 3D scaffolds. The obtained 3D scaffolds were dip-coated with TiO 2 and further utilized for the photocatalytic degradation of dyes. The photocatalytic efficiency of the 3D scaffolds was evaluated by the degradation of methylene blue in water. It was found that 3D scaffolds coated with TiO 2 showed a 40% higher degradation rate in comparison to bare 3D scaffolds under UV irradiation, which determines the significant role of TiO 2 in the organic dye degradation. The better efficiency of 3D scaffolds coated with TiO 2 , compared with uncoated BSG 3D scaffolds is attributed to a better recombination rate, and the migration of electrons to the surface of the scaffold, where the charges participate in the photodecomposition of MB dye. The efficiency of the scaffolds was assessed for five consecutive cycles. The degradation efficiency after the fifth cycle was 75%, confirming the stability of the system. [ABSTRACT FROM AUTHOR]

Expansive soils poses significant challenges in civil engineering projects, yet construction on them in many circumstances is unavoidable. Soil modification, therefore, is one of the finest options for improving the expansive properties of such soils. This study uses commercially available Sodium Bentonite as an expansive soil, where Recycled Glass Powder (RGP) alone and in combination with Polypropylene Fiber (PPF) are used as modifiers. RGP in the percentages of 5%, 10%, 20%, and 30% by dry weight, and 20% RGP in combination with PPF in the proportions of 0.25%, 0.5%, and 1.0% by dry weight of the soil sample were used in the study. Various tests to evaluate the index and engineering properties of both virgin and modified soil samples were carried out, including Atterberg limits, linear shrinkage (LS), specific gravity, compaction, free swelling index (FSI), expansivity index (EI), and one-dimensional consolidation test. Moreover, scanning electron microscopy and zeta-potential test were carried out to analyze the microstructural and electrokinetic properties of modified soil. The results demonstrated a significant decrease in LS (35.43%), FSI (62.23%), EI (50.29%), swelling index (37%), and compression index (22%) with the addition of 30% RGP. Furthermore, incorporating 1% and 0.5% PPF showed a remarkable decrease in LS (50%), and EI (31.78%), respectively as compared to the base soil mix with 20% RGP. Overall, recycled glass powder (RGP) and polypropylene fiber (PPF) as modifying agents hold strong potential for enhancing the expansive and swelling properties of highly expansive bentonite clay, offering promising solutions for construction challenges associated with expansive soils. [ABSTRACT FROM AUTHOR]

Briquettes made from carbonized agricultural residues present sustainable material alternatives to wood charcoal and firewood for commercial and industrial applications. However, these briquettes are plagued by property weaknesses including low drop strength and thermal efficiency. Therefore, this study focuses on enhancing the physical, mechanical and thermal properties of composite briquettes produced from carbonized banana peels and waste glass. Composite briquettes comprised of banana peels biochar and waste glass powder (0%, 5%, 10%, 20%, 30%, 40%, and 50%) were developed, characterized, and evaluated using thermo-gravimetric analysis and bomb calorimetry to determine thermo-physical properties and higher heating values, respectively. The thermal efficiency and emissions (CO, CO2, and PM2.5) were assessed using the water boiling test and an emissions monitoring system. Proximate analysis revealed that moisture content, volatile matter, fixed carbon, and ash content of the developed briquettes ranged from 2.5 to 9.7%, 19.2 to 37.2%, 28.7 to 55.6%, and 7.2 to 44.9%, respectively. Drop strength for the briquettes was 84% without waste glass in the composite, increasing to 94–98% with waste glass included in the composite matrix. Higher heating values ranged from 20.1 to 35.8 MJ/kg. Thermal efficiency rose from 22% with no waste glass powder to 40% with 50% waste glass powder addition, while CO and CO2 emissions decreased from 41 to 11 ppm; and 50 to 15 ppm, respectively. PM2.5 remained constant across all banana peel biochar waste glass composites. Notably, even a modest 10% waste glass composition significantly improved drop strength and thermal efficiency, but higher waste glass percentages correlated with elevated ash values and reduced higher heating values. Therefore, the developed composite briquettes can be used in commercial and industrial applications including in some industrial boilers. [ABSTRACT FROM AUTHOR]

This study presents the development of multicomponent glasses for glaze layers for dental yttria‐stabilized tetragonal zirconia (Y‐TZP). The samples were melted in the temperature range of 1 250–1 400°C and were cast in water to obtain a frit. The frits were grounded to a powder with a particle size of less than 40 µm. To study the crystallization tendency of melted glasses, they were thermally treated at 800°C and X‐ray diffraction analyses were performed for both types of samples. The structure of the glasses was investigated by the Fourier‐transform infrared spectroscopy. The thermal expansion coefficient, CTE, the glass‐transition temperature, Tg, and the softening temperature, Ts, were defined. To test the glaze layer on zirconia ceramic, glass powders with different compositions were mixed with modeling fluid and applied on zirconia specimens and then fired at 800°C in a vacuum dental furnace. Scanning electron microscopy, SEM, was used to observe a cross‐section of the glass–ceramic contact on a glazed zirconia ceramic specimen. Glass with the highest content of alkaline oxides is characterized by the closest CTE to zirconium ceramics (10.10−6 K−1), the greatest transparency and good fluidity, and shows good adhesion to the zirconia. The glaze layer is homogeneous without cracks, pores, and crystals. [ABSTRACT FROM AUTHOR]

The research on low-temperature lead-free glass is of great significance for the miniaturization, integration and intelligence of current electronic products, as well as environmental protection. In this article, we report the preparation of low-temperature lead-free B 2 O 3 -BaO-ZnO-SiO 2 -Al 2 O 3 -TeO 2 glasses by a melt-quenching technique. With the increase of TeO 2 content in glass, the glass transition temperature and melting temperature of sintered glass powder decrease, while its wettability and acid corrosion resistance show an increasing trend. The application of glass powder in the sintering experiment of terminal electrode slurry further proves this viewpoint. Compared with the poor sintering performance of the slurry with TeO 2 -free glass powder, the slurry containing TeO 2 glass powder forms a very dense sintered solid, and the sintered slurry is tightly bonded to the ceramic substrate. [ABSTRACT FROM AUTHOR]

Glass-ionomer cements (GICs) are used in various applications in clinical restorative dentistry. In this study the effect of CaF 2 content of the glasses on microstructure, thermal and mechanical behaviors of the synthesized glass ionomer cements was investigated. The results showed that by adding CaF 2 at expense of SrF 2 the first exothermic temperature (T E) of the glass was reduced from 735 to 704 °C and the compressive strength was increased from 42.0 ± 1.29 MPa to 60.3 ± 1.5 MPa as well. These substitutions led to extending of liquid-liquid phase separation in the glass. The enhancement of mechanical properties demonstrated through the process of annealing glass powder at temperatures below half of the glass transition temperature. This technique contributes to the improvement of mechanical properties by decreasing the residual stress and fostering the separation of amorphous phases. The formation of phase separation appears to be a significant factor in improving the mechanical properties of the oxyfluoride cements. [ABSTRACT FROM AUTHOR]

In this paper, the mechanical and durability properties of aerated blocks are discussed. Aerated blocks are prepared using different cementitious materials with an alkaline solution in the absence of aluminium powder. The proportions of raw materials are chosen after performing two mix trials P1 and P2, keeping the density of the blocks constant at 800 kg/m3. Each mix is further tested under six curing mechanisms, namely, normal water curing, humidity chamber curing (at 50°C and 70% relative humidity) for 6 h and 10 h, curing by oven drying at 180°C for 6 h and at 80°C for 24 h and using an accelerated curing tank (ACT) at 65°C ± 5°C for 10 ± 2 h; this is termed trial 1. In trial 2, the best curing mechanism is taken and construction and demolition wastes (CDW) are substituted at different proportions in place of fly ash in both the mix proportions. In addition, trial 3 investigates the best mix proportions by substituting glass powder at 50% and 100% with fly ash and CDW, respectively. It is observed from experiments that aerated blocks manufactured with 50% CDW and heat curing by ACT showed high mechanical and durability properties after 7 days of hardening. [ABSTRACT FROM AUTHOR]

FFF (fused filament fabrication) is a type of 3D printing that utilizes filament for part creation. This study proposes using by-products or waste to replace part of the plastic in FFF filament, reducing environmental impact. The aim is to maintain a simple manufacturing process involving extrusion on a single-screw desktop machine followed by printing. The plastic matrix comprises polylactic acid (PLA) and polyethylene glycol (PETG), with added powdered by-products: seashells, car glass and mill scale (metal). Additives will be incorporated at 10% and 20% by weight, with two grain sizes: up to 0.09 mm and up to 0.018 mm. Mechanical tests (tensile, flexural and hardness) and thermal characterization tests will be conducted. Findings suggest adding 10%w powder of any variety to PETG increases tensile strength up to 48%, with metal powder (mill scale) showing the highest enhancement, even at 20%w, resulting in a 41% increase. Conversely, adding powder to PLA worsens mechanical properties without stiffening the material; instead, the elastic modulus decreases. Metal grain size has minimal impact, with grain sizes lower than 0.09 mm optimal for PLA. Thermal conductivity in polymers blended with powder additives is lower than in virgin polymers, likely due to air void formation, supported by density and microscopic evaluations. This research underscores the potential of utilizing waste materials with a simple FFF filament production to enhance sustainability in 3D printing practices. [ABSTRACT FROM AUTHOR]

Optimally designed silver–silicon (Ag–Si) contacts, based on silver (Ag) paste screen printing and the rapid sintering process, are widely utilized in mainstream crystalline silicon solar cells, enabling to reduce contact resistance and high photo‐conversion efficiency. Ag powder is the largest conductive component in Ag paste, but its impact on the formation of Ag–Si contacts lacks in‐depth research and comprehensive understanding. In this work, it is demonstrated that the oxygen adsorption capacity of silver powders affects the formation of Ag–Si contacts by enhancing the reactivity of Ag powders with glass frits, and has a significant effect on the performance of devices. The generation of Ag2O introduced by surface‐absorbed oxygen promotes the transformation of [TeO4] triangular bipyramidal into [TeO3] triangular pyramid, thus destroying the network structure of the glass frits. This structural decay accelerates the spreading of glass frits in the bulk, causing the glass frits to come into contact with SiNx layers earlier and facilitating the formation of the Ag–Si contacts. In this work, not only a complete picture of the interaction between Ag powder and glass frits but also a new direction is provided to optimize the Ag–Si contacts. [ABSTRACT FROM AUTHOR]

Concrete, the construction industry's most utilized construction material, has transformed the environment and the modern built-up lifestyle. Although concrete is a first-rate supplier to the carbon footprint, it is imperative for buildings to display sustainable characteristics. Scholars have explored techniques to lessen the carbon footprint and the way to put into effect strategic waste control plans in which waste is reused. This study explores the dual benefits wherein concrete ingredients are replaced through abandoned waste which reduces the unwanted waste materials that have a substantial carbon footprint and thus results in the recycling of waste as part of a sustainable economic system. In this study, timber ash is utilized as a partial substitute for sand and cement, crumb rubber and waste glass as a partial substitute for sand, recycled concrete, and waste glass as a substitute for gravel. Characteristics studies were done to check the influence of each waste replacement on the modulus of elasticity of concrete. More than sixty-five combinations of waste have been examined to attain the modulus of elasticity of concrete. A total of about 200 concrete cylinders were cast to provide at least three cylinders for each generated data point. Three different ASTM standards were utilized to determine the modulus of elasticity of each mix. Four mixes comprising of the combination of two waste materials and two mixes comprising of the combination of three waste materials replacing natural materials were determined to exhibit an equal or superior modulus of elasticity of the control mix of 25 GPa. [ABSTRACT FROM AUTHOR]

A new ultra-high strength concrete, in which oxidized graphene nanoplatelet (GO) and hollow glass powder (HGP) are added, has been developed by authors. This paper presents the material properties of the concrete such as workability, compressive and tensile strengths, internal micro structure (SEM and MIP) as well as air-tightness which was tested using an equipment developed in this study. Test results show that workability and tensile strength significantly increase by a small addition of HGP, and that cGO (GO product of company c) and HGP are well dispersed without agglomeration effect, resulting in more than 20% of reduction in porosity. It is also observed that air-tightness increases by 40% compared with conventional ultra-high strength concrete due to reduction in porosity; thus, new ultra-high strength concrete is anticipated to be effectively used for structures that requires air-tightness such as hyperloop tube. Consequently, it was observed that the workability and mechanical properties of UHSC were increased when cGO and HGP were used instead of silica fume (SF), and authors believe that utilization of new material would contribute to the change in manufacturing method and increase in mechanical properties of concrete. [ABSTRACT FROM AUTHOR]

Polymer adhesives have considerable mechanical and environmental privileges; however, their high price makes them uncommercial for common uses. This study investigates the incorporation of recycled or byproduct fillers in epoxy resin‐based composites to assess their mechanical properties, environmental impacts, and cost efficiency. The fillers examined include fly ash, glass powder, slag, silica powder, and limestone powder. Tensile, compressive, and fracture tests were conducted on composites with various filler proportions (0%–80% by weight). From microstructure observations, round (fly ash, glass powder) and rough (slag, silica, and limestone powder) morphologies are seen. Also, it is seen that all the fillers are well distributed in the matrix; with the increase of filler content, the air voids increase. The tensile and compressive results indicate that adding fillers improves the composite's strengths, with up to a 20% increase compared to neat epoxy resin. However, when filler contents exceed 40%, the strengths decrease. Fracture toughness values also decrease with increasing filler content. Comparing the results with those of other studies indicates the similarity of trends. Cost‐strength and CO2eq‐strength curves were evaluated to assess the financial and environmental aspects. The composites show potential for cost efficiency but may have some environmental drawbacks compared to traditional construction materials like cement concrete. Highlights: The incorporation of recycled or byproduct fillers in epoxy resin composites.Examined fillers include fly ash, glass, slag, silica, and limestone powder.Tensile, compressive, flexural, and fracture tests were conducted.SEM and failure patterns were analyzed, and similar studies were compared.Cost‐strength and CO2eq‐strength data evaluated. [ABSTRACT FROM AUTHOR]

This study assesses the compressive strength and drying shrinkage behavior of cement and LC3‐50‐based cementitious composites containing glass powder. A total of four, i.e., 20, 35, 50, and 60 MPa, strengths of cementitious composites were targeted by varying the mix composition and water‐to‐cement ratios. In all four composite mix types, locally available glass powder was used as 0, 5, 10, and 15% added as a partial replacement of cement and LC3‐50. The novelty of this research is the addition of waste glass powder as an alternative to silica fume, especially in a high‐strength composite (including 50 and 60 MPa). The aim was to investigate the efficiency of waste glass powder in providing eco‐friendly composites. The compressive strength was determined following ASTM C 109 standard and the drying shrinkage test followed ASTM C 157 standard. The results of compressive strength in the enhancement using up to 10% waste glass powder are beneficial in enhancing strength and reducing drying shrinkage. Furthermore, the use of LC3‐50 initially reduced compressive strength up to 14 days while increased at 28 days compared to OPC. Contrariwise, the initial drying shrinkage was higher in LC3‐50 specimens and lower at later ages compared to OPC. A detailed investigation of existing shrinkage models for mortar/composite is assessed, and limitations are also discussed. [ABSTRACT FROM AUTHOR]

The possibility of obtaining high-strength vitrified bricks based on loess by adding 20% of waste glass powder was established. At the same time, the amount of moisture in the material should be close to 10%, which corresponds to the dry-pressing technology. [ABSTRACT FROM AUTHOR]

Gradient refractive index (GRIN) lenses have recently become a hot topic in compact imaging and achromaticity. Current research focuses on exploiting GRIN materials and upgrading the preparation technology. In this study, infrared (IR) GRIN materials were successfully prepared by spark plasma sintering of multilayer chalcogenide glass (ChGs) powders. ChGs powders were derived from the Ge20Se80‐xTex series glasses (x = 0–28 mol%) with a maximum refractive index difference (Δn) of 0.25. The similar glass transition temperatures (ΔTg < 10°C) promote efficient sintering of multilayer powders. Six‐, eight‐, and ten‐layer powders of different compositions were rapidly sintered with a thickness of 600, 300, and 200 µm per layer, respectively. Such tiny layer thickness enables the GRIN materials to exhibit nearly linear refractive index variation. Energy dispersive spectroscopy line scans well characterized the gradient variation of GRIN. The maximum deviation of the refractive index gradient from the fitted target line was only ± 0.016 for the 10‐layer GRIN. The sintered GRIN shows excellent IR transparency, which is of great interest for mid‐wave and long‐wave infrared imaging. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the impact of the Kovar glass content on the mechanical and electrical properties of Si3N4–Kovar composites sintering at air atmosphere. To achieve this, Si3N4–Kovar composites were prepared using molding technology with the Kovar glass powder ranging from 20 to 70 wt%. The phase composition, morphology, bulk density, apparent porosity, flexural strength at room temperature, dielectric constant, and dielectric loss of the composites were all examined in relation to changing the Kovar glass content. During the sintering process, the α‐quartz on the surface of Si3N4 particles acted as the crystal nucleus, inducing the crystallization of the glass at the wetting position that the Kovar glass and the surface of the Si3N4 particles. A small amount of the β‐quartz phase was crystallized at 750–850°C, followed by a large amount of the β‐quartz phase crystallizing above 900°C. Additionally, some β‐quartz phase transformed into the metastable β‐cristobalite phase that could exist below 1470°C. During the cooling process, the β‐cristobalite phase transformed into a low‐temperature α‐cristobalite phase, while the β‐quartz phase transformed into a low‐temperature α‐quartz phase. The results indicate that the Si3N4–Kovar glass composite with 60 wt% the Kovar glass content sintered at 900°C exhibits higher density (1.88 g/cm3), lower porosity (25.4%), higher flexural strength (55.34 MPa), lower dielectric constant (3.46), and lower dielectric loss (4.26 × 10−3). [ABSTRACT FROM AUTHOR]

Recycled soda-lime glass powder is a sustainable material that is also often considered a filler in cement-based composites. The changes in the surface properties of the glass particles due to the treatments were analyzed by X-ray photoelectron spectroscopy (XPS) and optical spectroscopy. We have found that there is a relatively high level of carbon contamination on the surface of the glass particles (around 30 at.%), so plasma technology and thermal annealing were tested for surface cleaning. Room temperature plasma treatment was not sufficient to remove the carbon contamination from the surface of the recycled glass particles. Instead, the room temperature plasma treatment of recycled soda-lime glass particles leads to a significant enhancement in their room temperature photoluminescence (PL) by increasing the intensity and accelerating the decay of the photoluminescence. The enhanced blue PL after room-temperature plasma treatment was attributed to the presence of carbon contamination on the glass surface and associated charge surface and interfacial defects and interfacial states. Therefore, we propose blue photoluminescence under UV LED as a fast and inexpensive method to indicate carbon contamination on the surface of glass particles. [ABSTRACT FROM AUTHOR]