Silica - Science topic

The study of plant use and the biocultural knowledge of Aboriginal peoples in South-Eastern Australia has received growing attention in recent decades, but the identification of plant remains in archaeological contexts is largely limited to macrobotanical remains and pollen analysis. This study explores the potential of extracting and analysing phy...

This paper presents an experimental-statistical study investigating the influence of five joint properties: density, filling type, angle, aperture, and roughness on the longitudinal wave velocity (LWV) of concrete samples. To achieve this, each of the five properties is categorized into distinct groups with specific intervals. Concrete samples meas...

Multi-wavelength Raman fiber lasers provide a flexible and controllable option for applications such as generation of terahertz radiation, deep-tissue bioimaging and so on. However, conventional multi-wavelength Raman fiber lasers employing silica fiber as the gain medium are constrained by the narrow Raman gain spectrum, which limits their tunabil...

Brillouin light backscattering from isotropic platelet samples involves the contribution of two phase-matched longitudinal acoustic phonons. A primary, stronger, signal is provided by the usual condition of a phonon wavevector collinear to and twice as large as the incident photon wavevector inside the medium. After reflection of incident light on...

The surface charge plays a crucial role in electrokinetic flow within micro/nanochannels. The charge on silica surfaces originates from the protonation and deprotonation of the silanol functional groups. Instead of being set at a constant value, the surface charge density in this paper depends on the solution pH and ion concentration. Analytical an...

Explosive volcanic eruptions, driven by magma fragmentation, pose significant geohazards due to their rapid energy release and widespread dispersal of pyroclasts. High magma viscosity promotes brittle fragmentation by limiting volatile escape and enhancing internal pressure buildup. Although recent studies have recognized that iron-titanium oxide n...

We demonstrate excitation of the circularly symmetric LP0,m modes with microstructured monolithic binary phase plates etched in fused silica. The principles, design, and manufacturing of the phase plates are described. We show results of experimental mode excitation using the phase plates, resulting in total excitation efficiencies above 65% of the...

The optical force density acting in transparent dielectric media due to short laser excitation is theoretically analyzed. For typical laser pulses with picosecond duration, the momentum component of the optical force becomes of the same order of magnitude as the stress component, enhancing the overall optomechanical effects. Simulations of the opti...

Porous and spherical silica nano‐shells (PSNSs) have garnered significant attention due to their potential applications in drug delivery systems, water treatments, etc. This study produced and characterized seven different PSNSs (S‐1,2,3,4,5,6,7) using new methods. The selected products' (S‐4 and S‐7) surface areas were determined to be 702.2 m²/g...

Alachlor, acetochlor, and metolachlor are organochlorine herbicides extensively used for weed control in agricultural practices, yet their use is prohibited within the European Union due to environmental and health concerns. These compounds and their degradation products exhibit high environmental persistence, necessitating reliable and rapid analy...

The selective oxidation of Ethylbenzene to acetophenone is a crucial transformation in organic synthesis, as acetophenone is a key intermediate in the production of pharmaceuticals, fragrances, and fine chemicals. This study focuses on developing an efficient heterogeneous catalyst for this oxidation reaction under mild reaction conditions. Mesopor...

In this paper, a dual-core photonic crystal fibre (DC-PCF) sensor is proposed featuring a rectangular analyte channel, designed for fuel Adulteration sensing. The cladding area of this sensor includes rectangular air holes. The proposed fiber uses silica as a substrate material, and it is operating within a wavelength range of 2 to 3 μm. PCF sensor...

Here, two types of silicates (ex-situ SBA-15 and in-situ SiO2) were employed along with cardanol epoxy (CE) separately to perform the organic–inorganic hybrid coating over cotton via layer by layer (LBL) approach and compared. The silicates were preferred as primary layer along with silane cross-linkers and CE as a secondary layer for the first tim...

The article presents results of an inventory of fences and small-scale architectural structures built from soft silica limestone in area between of the Warta and Ner rivers (central Poland). This natural local building material was widely used in traditional rural and small-town architecture until the late 1960s. The relationship between the charac...

Milli-Kelvin atomic force microscopy (mK-AFM) presents an ongoing experimental challenge due to the intense vibrations in a cryogen-free dilution refrigerator and the low cooling power available at mK temperatures. A viable approach is to make the system exceptionally rigid and thermally insulating to decouple external vibrations and isolate heat d...

Iron phosphide (FeP) has emerged as an efficient catalyst for converting palm oil, a biomass-derived feedstock, into bio-jet fuel through the hydrocracking process. The catalytic performance of FeP is strongly influenced by the choice of support material. In this study, microporous MWW-type zeolites (MCM-22 and MCM-36) and mesoporous materials (MCM...

A new series of cobalt-modified hexagonal mesoporous silica catalysts, denoted Co-HMS-n, where n corresponds to the molar ratio (Si/Co = 10, 20 and 50), was synthesized to evaluate its catalytic activity in the presence of NaBH4 in the degradation of metronidazole (MNZ), an antibiotic known for its low non-biodegradability in aquatic environments....

This study investigates the influence of amorphous and crystalline silica derived from rice husk (RH), a sustainable agricultural waste, on the phase composition, microstructure, hydrothermal ageing resistance, mechanical properties, and biocompatibility of Alumina Toughened Zirconia (ATZ) biocomposites. The research supports the bio-circular econo...

Stress softening, known as the Mullins effect, has a significant effect on the durability and performance of filler-reinforced rubber, making it a critical issue in designing products for practical applications. While empirical equations are widely used, they fail to capture the intricate and nonlinear behaviors that are characteristic of filler-re...

This study integrated high‐throughput computational modeling with experimental validation to investigate rare earth (RE) phosphates as potential environmental barrier coatings (EBCs) for SiC‐based ceramic matrix composites (CMCs). Although RE silicates have been widely studied for EBC applications, they are prone to degradation due to water vapor c...

We report observations of unusual first plastic events in silica and metallic glasses in the shear startup regime at applied strain two orders of magnitude smaller than yield strain. The (non-affine) particle displacement fields during these events have complex real space structure with multiple disconnected cores of high displacement appearing at...

Addressing the challenging field of chemoenzymatic dynamic kinetic resolution (DKR) of tertiary alcohols, for which so far only one example exists in the literature, we combined biocatalytic esterification and oxovanadium-catalyzed racemization, operating both steps in two different compartments of one reactor. The compartmentalization of the two h...

Au-doped photonic crystals offer considerable potential for boosting optical signals, however, precisely controlling the distance between luminescent particles and Au nanoparticles (NPs) faces severe challenges. We proposed a “filling” technique to prepare porous Au-doped inverse-opal PC (IOPC) with encapsulated Au NPs uniformly dispersing in insul...

The beneficiation of bauxite ore generates significant quantities of tailings, primarily composed of kaolinite and residual gibbsite, the latter still amenable to metallurgical recovery. In this study, bauxite tailings were reprocessed based on particle size classification from 30 µm to 2 µm, obtained by sedimentation. The resulting fractions consi...

This study investigated the optimization of synthesis parameters for producing nanostructured SiO2 from Ethiopian pumice for use as rubber reinforcement. Important variables such as pH, sol‒gel synthesis temperature, stirring rate, calcination temperature, sodium silicate modulus, NaOH concentration, and H2SO4 concentration were systematically vari...

Deoxidation is a key process in refining liquid steel and enhancing its cleanliness. O removal from the melt is typically achieved by adding elements with a high affinity for O, such as Al, Si, or by adjusting a specific Mn/Si ratio in the melt. In the production of high-Si steels, precise knowledge of the equilibrium between the liquid metal and s...

Glass-based microfluidic devices are essential for applications such as diagnostics and drug discovery, which utilize their optical clarity and chemical stability. This review systematically analyzes pulsed laser micromachining as a transformative technique for fabricating glass-based microfluidic devices, addressing the limitations of conventional...

Core-shell nanoparticles, particularly those having a gold core, have emerged as a highly promising class of materials due to their unique optical and thermal properties, which underpin a wide range of applications in photothermal therapy, imaging, and biosensing. In this study, we present a comprehensive study of the thermal dynamics of gold-core...

This study investigates the use of coal fly ash as a filler in Room Temperature Vulcanization (RTV) silicone rubber to enhance its mechanical properties. Fly ash, which contains silica, has the potential to improve the strength of the polymer. The research aims to optimize the composition of fly ash in RTV silicone rubber composites using the quadr...

In this study, the dual effect of fumed silica and conventional curing systems such as peroxide and sulfur on the hydrophobicity of ethylene‐propylene‐based rubber (EPR) compounds has been examined. A variety of silica samples in different amounts and two types of curing agents were used to determine the contribution to the hydrophobic character of...

A pyrazole amide grafted onto a silica surface was synthesized to form a new hybrid adsorbent for methyl orange (MO) removal. The synthesized hybrid adsorbent SiNL was characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X‐ray diffraction (XRD), scanning electron microscopy (SEM), and Brunauer–Emmett–Te...

Cell-like model chemical systems are powerful tools that can be used to explore the role of intercellular coupling on population level behaviors in communities of biological cells. We present a new method for fabricating such micro-reactors using the photosensitive Belousov–Zhabotinsky (BZ) reaction system employed in silica microparticles. These B...

Inorganic nanofillers have been extensively employed to tailor or enhance the properties of polymer nanocomposites, wherein the morphology of the nanofillers plays a pivotal role. Here, the use of a directional force is demonstrated to drive the in situ growth of inorganic silica nanofillers with controllable morphologies, including silica spherica...

In this study, we demonstrate a novel approach for the reduction of silica to silicon nanoparticles using a CO2 laser beam. By irradiating a mixture of silica and carbon with a high-intensity laser, we observed the rapid formation of silicon nanoparticles. The emission spectra from the reaction zone were monitored using spectroscopy, which proved e...

PT. MKP currently processes silica sand manually using PTO pipes and screening units. This method yields a silica (SiO₂) content of 97.48%. However, market demand—particularly from the glass industry—requires the company to supply silica sand with a minimum SiO₂ content of 99.2%, along with higher production capacity. To meet these quality and quan...

Single-frequency fiber laser is of principal role either in frontier interdisciplinary science or advanced practical applications. Here, we present a 1-kHz-level linewidth 915 nm all-polarization-maintaining Nd³⁺-doped single-frequency all-fiber laser featuring a ring cavity configuration. Particularly, a piece of commercial unpumped Nd³⁺-doped sin...

The anhydride-cured epoxy resin with silica micro-powder (SAE) is widely used in electrical equipment due to its excellent properties. However, its three-dimensional network structure makes degradation and recycling difficult. Conventional disposal methods, such as incineration or landfill waste resources, harm the environment. Therefore, it is cru...

Barley husks (BH), an agricultural by-product rich in carbon and silica, have been utilized as a sustainable precursor for synthesizing carbon anode materials for lithium-ion batteries (LIBs). A comparative analysis with graphite, the conventional anode material, demonstrates the potential of BH-derived carbon as a viable alternative. Material char...

Due to the lack of targeting specificity, rapid clearance, and high toxicity associated with small molecule drugs in tumor treatment, the design of an effective drug delivery system is crucial. To better overcome physiological barriers and achieve prolonged tumor retention, nanoparticles (Fe3O4@SiO2@Au, termed FSA‐NPs), made of core–shell NPs (Fe3O...

Produced water re-injection (PWRI) is the water management strategy with least environmental impact during petroleum recovery. A major challenge, however, is clogging of pores in the injection reservoir by particles suspended in the produced water. Basic understanding of transport and retention of particles in porous media is required to better han...

Optimization of rare-earth (RE) doped devices for laser applications necessitates a combination of precision material engineering and advanced performance enhancement strategies. This study presents a novel investigation, to our knowledge, into cluster dynamics in Er-doped glass, utilizing localized CO2 laser heating to simulate the high-temperatur...

Boron nitride nanotubes (BNNTs) are predicted to be promising one-dimensional nonlinear optical materials, but to date, only one experimental observation has been made using individual nanotubes. In this work, second harmonic generation (SHG) was achieved from free-standing bulk BNNT sheets and BNNT coatings on silica substrates. Focusing femtoseco...

A tapered fiber coupler (TFC) whose dispersion turning point (DTP) can be widely and precisely tuned by a 980 nm laser was designed and fabricated in this research. It offers the potential application advantage of adapting to environmental changes while providing both a wide detection range and high sensitivity. Theoretical studies indicate that th...

Quantitative analysis of siliceous microfossils in a dated sediment core from Lake Michigan reveals the anthropogenic history of pelagic conditions from the last ~ 160 years. Sediments deposited before the twentieth century contained low diatom abundances comprising species associated with oligotrophic conditions. Diatom-assemblage reorganization i...

Although stress is a critical factor in many ultrafast laser-based fabrication techniques, its relationship to different laser operating parameters remains poorly understood. Here, we investigate the stress landscape within fused silica generated by ultrafast laser pulses, with repetition rates of 100 − 900 kHz and pulse energies of 200 − 4000 nJ,...

In this study, we utilized a comprehensive dataset comprising over 19,000 data points with inputs represented by coordinates (x, y) and the corresponding output denoted as concentration (C). The case study was analysis of mesoporous material for adsorption separation of target solute from aqueous solution. Mass transfer and machine learning evaluat...

Impregnation of nanocrystalline magnesium and iron at different concentrations into Beta zeolite was studied employing two techniques: the Traditional Method (TM) and Mechanical Milling (MM). It is known that hydrogen is a potential fuel for the development of the society in a friendly environment with the world; however, there are great challenges...

Resolving riverine biogeochemical inputs in ocean biogeochemistry models is pivotal for capturing the spatiotemporal variability of nutrients and carbon in coastal regions and in the global ocean. ECCO-Darwin is a pioneering data-assimilative global-ocean biogeochemistry model, which, to date, has focused on the pelagic zone. As a key step towards...

The pursuit of long-term data storage has increasingly turned toward DNA as a viable medium owing to its exceptional information density and longevity. Despite its potential, maintaining DNA integrity over extended periods is challenging. Here, we investigated the effectiveness of surfactant-mediated DNA compaction and cyclodextrin-driven decompact...

Catalyst deactivation due to carbon deposition and sintering poses a significant challenge to the efficient dry reforming of CH4 and CO2 into syngas, particularly at high Ni loadings. To tackle this difficulty, ordered mesoporous silicas with varied pore symmetries were employed as supports in this study to synthesize the Ni‐based catalysts using h...

Quasicrystals, characterized by long‐range order and the absence of translational symmetry, have attracted great attention due to their extraordinary physicochemical properties. Although quasicrystals have been discovered in various experimental systems, the formation mechanisms that yield quasicrystals at the mesostructural scale remain elusive. H...

In this specialty optical fibers and coatings presentation, topics related to the basics of optical fiber theory, fused silica fiber types, solarization resistance fiber, end tapered fibers, photonic crystal fibers, plastic (or polymer) fibers, rare earth-doped fibers (or active fibers), double/triple clad fibers, IR fibers, sapphire fibers, hollow...

A feasible new technique has been developed to extract nickel ions from synthetic industrial wastewater. This study successfully modified waste glass containing silica, sodium, magnesium, and calcium oxides using an acidification approach to develop and evaluate it as an effective precipitating agent for heavy metal ion recovery. The waste glass wa...

To investigate the effect of diamond-like carbon (DLC) film on the relative humidity (RH) dependence behaviors at the silica-silica interface, atomic force microscopy (AFM) silica cantilever was used to measure adhesion forces on it. The results show that DLC film can significantly reduce the magnitude of adhesion force and decrease its sensitivity...

Proton exchange membrane (PEM) is a key component of PEM fuel cells, where the membrane plays a decisive role in determining system efficiency and overall performance. The modification of PEMs with hydrophilic dopants represents a promising strategy for extending the operational range of these devices, particularly in low-humidity and high-temperat...

Further elucidation is needed to clarify the incomplete understanding of adhesion force’s contact time dependence. AFM silica cantilevers were employed to probe this dependence by measuring forces on highly oriented pyrolytic graphite (HOPG) across relative humidities (RH) of 10%~90%. Results indicate that adhesion forces on HOPG exhibited a time-d...

This study explores the fabrication of germanium-doped silica optical fibers using Modified Chemical Vapor Deposition (MCVD) techniques to enhance dosimetric properties for gamma-ray detection in blood irradiators. Accurate dose mapping, essential for preventing graft-versus-host disease, requires radiation exposure in the range of 15 Gy to 50 Gy....

This study investigates the aerothermodynamic behavior of eco-friendly functionally graded materials (FGMs) in composite plates subjected to supersonic airflow and thermal loads, critical for aerospace applications where structural stability, flutter suppression, and thermal resistance are paramount. Traditional metal-ceramic FGMs are replaced with...

Photoacoustic sensing exhibits ultra-high sensitivity and immunity to electromagnetic interference in the field of ultrasonic sensing technology. In underwater acoustic detection, to address the escalating sensing demands, there is an increasing need for sensor systems that are miniaturized, highly sensitive, and capable of broadband response. This...

The ratio cost/efficiency of electrodeposited composite coating has boosted the development of this method in the last decades. Thus, electrodeposited nickel with silica particles as reinforcement was successfully designed and the conditions to increase particles in the composite are better understood. Those composites' morphological, mechanical, a...

Brillouin light scattering (BLS) is a powerful experimental tool that can be used to get insights into the fundamental and applied properties of matter, like dispersions of quasiparticles in a solid, as well as their spatio-temporal dynamics. Many applications of light scattering favor the use of optical fibers in place of free-space optics. In thi...

This study investigated the use of Moroccan diatomite in its raw and calcined forms in mortar as a partial replacement for cement to reduce the primary energy consumption in cement production. For this purpose, a thermophysical and mechanical study was carried out. In addition, the energy consumption and global warming potential (GWP) associated wi...

Aqueous zinc-ion batteries (AZIBs) have garnered significant attention as promising energy storage systems due to their inherent safety and cost-effectiveness. However, they still face considerable challenges, including severe corrosion and dendrite formation during cycling, which lead to substantial polarization and eventual short-circuiting. To a...

The photocatalytic regeneration of NADH represents an effective means of mimicking photosynthesis, but confronts the challenges of the charge separation, electron transfer, and the selectivity control in the surface reduction stage. Herein, we report a multifunctional composite material that embeds β‐ketoenamine‐linked nano TPTTA covalent organic f...

The structural engineering field is advancing rapidly. Fly Ash contains silica, similar to cement. This study examines the use of Fly Ash waste as a cement substitute in concrete production, with polycarboxylate added. Fly Ash was used at 15% and 30% with polycarboxylate at 1% and 2%. The target compressive strength was 25 MPa, with normal concrete...

Introduction A recent meta-analysis confirmed that Chest Xray (CXR) has low sensitivity for the diagnosis of silicosis however the impact of this is unclear. We therefore re-estimated a previously published dose-response relationship between cumulative respirable crystalline silica (RCS) exposure and silicosis risk, under the assumptions that sensi...

The heightened development of power network infrastructure has necessitated enhanced performance requirements from rubber composites used in transmission lines. Ethylene propylene diene monomer (EPDM) rubber is the primary matrix component in many damping spacer rubber composites for these applications. However, due to flexible molecular chains, no...

Silica‐incorporated polyimide (PI)‐based mixed matrix membranes (MMMs) are emerging as promising candidates for gas separation. However, experimental evaluation of their performance is challenging due to the complex interactions between polymers and fillers and limitations in isolating individual transport mechanisms. This study employs Monte Carlo...

For the purpose of tackling the issue of sluggish identification speed and prolonged processing time resulting from the extensive network architecture of deep learning algorithms, this paper proposes Mix SwiftYOLOV5, a lightweight silicon ore recognition network based on YOLOv5, to decrease processing parameters and boost detection speed. Specifica...

Ultrafine nanosilica exhibits a strong tendency to form agglomerates, with sizes often several orders of magnitude larger than the primary particles. This agglomeration severely impairs its effectiveness in fluidization and other applications requiring uniform powder dispersion. To address this issue, the present study employed an assisted fluidiza...

Perovskite quantum dots (QDs) hold promise for next‐generation display applications but suffer from stability challenges, particularly thermal‐ and light‐induced photoluminescence (PL) quenching. Here, a fluoride post‐treatment (FPT) strategy is developed to address this challenge for CsPbBr3 QDs embedded in silica matrices (CsPbBr3/silica composit...

Inversion symmetry eliminates second-order nonlinear responses in materials that are commonly used in silicon photonics. The lack of effective methods to induce second-order nonlinearity in silicon photonic materials (silicon, silica, and silicon nitride) significantly hinders their applications in second-order nonlinear integrated photonics. Herei...