Silicon最新文献

This study presents an integrated approach to converting hazardous industrial paint waste and Prosopis juliflora biomass into renewable fuel via catalytic hydrothermal liquefaction (HTL) and enhancing its combustion performance using silicon dioxide (SiO₂) nanoparticles. The HTL process, optimized at 420 °C with 4 wt% acid-activated bentonite catalyst and a 2:1 biomass-to-waste paint ratio, achieved a maximum bio-oil yield of 49.26 wt%. The resulting bio-oil exhibited favorable physicochemical properties, including a high heating value (45.22 MJ/kg), low viscosity (33.29 cSt at 40 °C), and minimal oxygen content (1.84 wt%), confirming its suitability for compression ignition engine applications. Engine trials were conducted using a single-cylinder, four-stroke CI engine operating on diesel–biodiesel blends, with and without the addition of 100 ppm SiO₂ nanoparticles. The SiO₂-enhanced DB20 blend demonstrated superior combustion behavior, marked by increased cylinder pressure, higher net heat release, and a sharper rate of pressure rise. Performance metrics improved significantly, with Brake Thermal Efficiency (BTE) increasing by 7% and Brake Specific Fuel Consumption (BSFC) decreasing by 8% compared to the baseline DB20 blend. Emission analysis revealed notable reductions in carbon monoxide (CO), hydrocarbons (HC), and smoke opacity by 30–45%, attributable to the improved oxidation kinetics and thermal conductivity imparted by the SiO₂ nanoparticles. A marginal increase in nitrogen oxides (NOₓ) was observed due to elevated in-cylinder temperatures. Overall, the study confirms that HTL-derived bio-oil from industrial waste paints and P. juliflora, when blended with diesel and enhanced with SiO₂ nanoparticles, can serve as a high-performance, low-emission alternative fuel for CI engines. This approach supports waste valorization, emission cuts, and energy diversification, aligning with circular economy and green energy goals.

This research presents a one-dimensional photonic crystal structure designed for precise angle and refractive index detection through the optical Tamm state. Utilizing the transfer matrix method, the study explores system characteristics under specific Bragg scattering conditions. The proposed sensor structure incorporates a multi-frequency absorption configuration, achieving absorption rates exceeding 0.9 at three distinct frequency points. Adjustments in the incident Light angle and defect layer thickness induce red and blue shifts in the absorption peaks, while the spacing between these peaks can be controlled by the phase number and defect layer thickness. Among these configurations, one demonstrates exceptional properties, enabling the development of highly efficient refractive index and angle sensors. The structure operates as a refractive index sensor within a range of 1.3 to 2.7, with a sensitivity of 32.389 THz/RIU and an average figure of merit of 70.328. When applied as an angle sensor, it exhibits a sensitivity of 0.533 THz/degree, with a corresponding figure of merit of 1.57, covering an angular range from 30° to 70°. This innovative structure holds significant potential for enhancing sensor applications, contributing to advancements in optical detection and precision measurement.

Silica nanoparticles (NPs) are among the promising platforms for the delivery of a wide variety of drugs (either hydrophilic or hydrophobic drugs) especially hydrophobic low-soluble agents such as curcumin. Through using nanoplatforms, curcumin may become more bioavailable for more efficacy in the field of cancer therapy. Silica NPs with a wide span of applications, possessing mesoporous structure, namely mesoporous silica nanoparticles (MSNs) are widely manipulatable for this purpose. This review provides a comprehensive analysis of MSN-based drug delivery systems tailored for curcumin, focusing on (1) structural and functional engineering of MSNs to optimize loading efficiency and controlled release, (2) active targeting strategies (e.g., ligand conjugation) to improve tumor specificity, and (3) stimuli-responsive designs (pH-, redox-, or light-triggered systems) that enhance precision in diverse tumor microenvironments. We critically evaluate preclinical studies demonstrating how MSN-curcumin formulations amplify anticancer efficacy through synergistic modulation of apoptosis, angiogenesis, and metastasis pathways. The mechanisms of action in which curcumin asserts its effect on tumoral cells have also been presented by applying silica NPs. Furthermore, we discuss translational challenges and opportunities, emphasizing scalability, toxicity profiles, and combinatorial approaches with conventional therapies. This review establishes MSNs as a versatile and clinically promising strategy to unlock curcumin’s full potential in oncology.

This study presents an approach for designing of the biotransducers capable of detecting biological charges using silicon nanowires (SiNWs). The primary objective was to optimize the SiNW’s geometrical and electrical properties to establish consistent memristor behavior in the SiNWs, thereby enhancing its functionality for the precise biological detection. A conceptual model was developed to guide this optimization process, with real-time integration between COMSOL and MATLAB simulations allowing precise identification of key design features. Results reveal that the resistance of the SiNWs exhibits memristor-like behaviour and effectively affected by the surface and space charge conditions. Comprehensive performance analysis, particularly under varying surface and space charge densities, demonstrates the transducer’s high precision and sensitivity as a bio-to-electrical interface, essential for accurate biological charge detection. The distinctive memristive I-V characteristics and hysteresis loops further improve the device’s capability to detect charge variations, highlighting its potential as an electronic biotransducer with information-rich I-V characteristics, enabling precise charge sensing. The operation and role of the Memristive-SiNW (M-SiNW) in biocharge sensing can also contribute to the development of biosensors capable of label-free biological signal detection, enabling advanced applications in biotransducers, including high-sensitivity charge detection and compatibility with the integrated electronic circuits. This approach highlights the potential for the silicon nanowire-based transducers in diverse biosensing fields, offering precise and flexible solutions for the real-time biological monitoring.

This study aims to improve the dielectric and structural properties of polyvinyl alcohol (PVA)/chitosan(CS)/silicon dioxide (SiO₂)/tungsten carbide (WC) nanostructures for flexible pressure sensor application. The (PVA-CS/SiO₂-WC) films were fabricated by utilizing casting process. The results indicated that high distribution of SiO₂-WC NPs inside the PVA-CS medium and excellent incorporation between SiO₂-WC NPs and PVA-CS matrix. The dielectric properties findings showed that an increase in the dielectric parameters of PVA-CS with an increase in the SiO₂-WC nanoparticles content. The dielectric constant(ε′) and (σ_A.C) of PVA-CS increased about 58% and 66.5% with low values of dielectric loss(ε′′) ranged from 0.193 to 0.581 at 100 Hz, this result indicates that the (PVA-CS/SiO₂-WC) nanocomposites are suitable for diverse nanoelectronics applications. The dielectric characteristics of (PVA-CS/SiO₂-WC) nanocomposites were changed with an increase in frequency. The final results showed the PVA-CS/SiO₂-WC nanostructures exhibit superior pressure sensitivity, exceptional flexibility, and strong environmental resilience compared with other sensors.

In this research work, we specify the fabrication and characterization of three unique hybrid nanostructures that employ nanostructures as substrate components: porous silicon (PSi), gold nanoparticles (Au NPs), and tungsten oxide nanoparticles (WO₃). N-type silicon wafer oriented in the (100) direction was employed to fabricate PSi layers via photo-electrochemical etching (PECE) process. In this study, the etching conditions were set to a duration of 25 min and a current density of 20 mA cm². Gold salt (HAuCl₄) was utilized to synthesize gold nanoparticles through ionic reduction methods, subsequently deposited onto the PSi layer. The tri-type hybrid nanostructures were fabricated by dip-coating the Au NPs/PSi hybrid layer with WO₃ NPs. To characterize the WO₃ NPs/PSi and WO₃ NPs/Au NPs/PSi hybrid nanostructures, many analyses were conducted including Fourier transform infrared spectroscopy FTIR, atomic force microscopy AFM, field-emission scanning electron microscopy FE-SEM, X-ray diffraction XRD, energy dispersive X-ray spectroscopy EDX, and photoluminescence spectroscopy PL. The nanostructured WO₃ NPs/Au NPs/PSi exhibited a specific surface area (S.S.A) of around 6.23 m²/g. The specific surface area for gold nanoparticles (Au NPs) was 6.47 m²/g, while that for WO₃ NPs was measured at 8.25 m²/g. The NP surface densities of WO₃ NPs/PSi and WO₃ NPs/Au NPs/PSi were ~ 5.5 × 10⁷ and ~ 3.2 × 10⁹ NPs/cm², respectively. The produced tri-type hybrid nanostructures are inexpensive, easy to use, and ideal for gas-sensing applications.

This study investigates the design and application of a Centrifugal Cusp Magnetic Field (CMF) system, with a focus on its influence on melt flow during the Czochralski (CZ) crystal growth process. The CMF system comprises two cylindrical coils with hollow copper elements, cooled by a water-cooling system, and surrounded by an iron shield to control stray magnetic fields. The system's performance is analyzed through simulations based on Maxwell’s equations, with a multifrontal massively parallel sparse direct (MUMPS) solver used to solve the governing equations. The simulation model is validated by experimental measurements, demonstrating good agreement between simulated and measured magnetic flux densities. Key findings include the influence of magnetic shield thickness and shape on the magnetic flux distribution, with a notable impact on the stability and uniformity of the magnetic field. Application of the CMF to the CZ puller revealed that the induced Lorentz force suppresses natural convection currents in the molten silicon, reducing melt flow speed from 1.6 cm/s to 1.1 cm/s and improving the uniformity of temperature distribution. These results underscore the potential of CMF systems for enhancing the stability of melt flow and temperature in semiconductor manufacturing, with implications for optimized crystal growth processes.

The two-dimensional (2D) layered structure material was prepared by etching the precursor CaSi₂ with topological transformation. The effects of different drying methods on the morphological structure, elemental composition and electrochemical properties of siloxene samples were investigated. The results showed that the siloxene materials prepared by supercritical drying have the largest specific surface area and fast ion diffusion rate due to the reduction of interlayer stacking and aggregation. The supercritical drying protected the backbone structure of siloxene, resulting in better electrochemical properties. Siloxene-S has a specific capacitance value of 134 F g⁻¹ when the current density is 0.5 A g⁻¹. When the current density was increased to 4 A g⁻¹, the specific capacitance of Siloxene-S remained 96 F g⁻¹. The assembled Siloxene-S//AC device provided a maximum energy density of 5.89 Wh kg⁻¹ at a power density of 209.8W kg⁻¹, which confirmed that siloxene has broad application prospects as electrochemical energy storage material.

To broaden the disposal strategy of silicate wastes, a hydrothermal method inspired by previous work on the extraction of potassium from K-feldspar was proposed in this work to handle the representative silicates of feldspars, pyrophyllite, coal gangue, coal fly ash, and as a result, two typical small zeolites of analcime and hydroxycancrinite were obtained. Systematic ion exchange experiments under the existences of Li⁺, Na⁺, K⁺, Ca²⁺, Mg²⁺ in different conditions were conducted to evaluate their cation selectivity and capability. Results showed that Li⁺ was the only cation having positive feedback on the zeolite structure, in mixed-ion system solutions, it achieved efficient lithium silicate immobilization with a Li₂O content of 4.50 wt.%, while in a single-ion system (LiCl solution), the Li₂O content reached 9.40 wt.%. The immobilization capacities in both systems surpassed those of high-grade granitic pegmatite-type lithium ores (1.5–4 wt.%). The structure of hydroxycancrinite is always the same before and after ion exchange, and all of them are shelf silicate structures. The Spectral analysis identified the formation of Li-zeolite from hydroxycancrinite with the successful trapping of Li⁺ inside. The overall handling process provided a new way for the process of universal silicate wastes with further combination of lithium extraction from mixed cation solution system.

This study provides mechanistic insights into the microstructural evolution and property enhancement of secondary Al-Si-Zn-Fe-Cu alloys through the addition of Ni. A systematic investigation was conducted to evaluate the effects of varying Ni concentrations on the alloys' microstructure, mechanical performance, and electrical conductivity. It was found that the microalloying effect of Ni promotes the formation of eutectic silicon and homogenizes the constituent phases. The results demonstrate that the addition of Ni up to 0.3 wt.% leads to a more uniform component distribution and refined grain structure. This promotes a significant reduction in the size and number of coarse primary silicon particles and enhances the uniformity of silicon distribution. At the optimal Ni content, the alloy exhibits substantial improvements in hardness, tensile strength, and electrical conductivity, reaching 84.5 HV, 126.16 MPa, and 26.4% IACS (International Annealed Copper Standard), respectively. Moreover, Ni additions up to 0.3 wt.% elevate the initial melting temperature, peak melting temperature, and final melting point, while broadening the solidification range. However, when the Ni content exceeds 0.3 wt.%, it leads to the formation of primary silicon, coarsening of the Al-Ni–Fe phase, deterioration of the alloy's mechanical properties, and a reduction in electrical conductivity. These findings highlight the critical role of Ni in tailoring the morphology and distribution of silicon phases, offering valuable guidance for the design and optimization of high-performance secondary Al-Si-based materials with improved mechanical and physical properties.