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Inverted perovskite solar cells (IPSCs) suffer from significant non‐radiative recombination losses at the defective perovskite/C60 interface, limiting the efficiency and stability of perovskite/silicon tandem solar cells. Despite silicon oxide (SiOX) being a common passivation material in the silicon industry with higher electron selectivity than conventional atomic layer‐deposited alumina, its application in IPSCs is limited by its tendency to damage sensitive perovskite during processing. Here, an oblique angle evaporation method is developed to deposit a conformal, ultra‐thin SiOX layer without damaging the underlying perovskite. This SiOX interlayer not only chemically passivates under‐coordinated Pb2+ defects but also forms an n/n+ homojunction that provides effective field‐effect passivation, concurrently reducing recombination and enhancing electron selectivity. As a result, extending this strategy to two‐terminal monolithic perovskite/tunnel oxide passivating contact silicon tandem solar cells achieves a stabilized power conversion efficiency of 30.2%, representing one of the highest efficiencies reported for such tandems. More importantly, the robust inorganic nature of SiOX enables it to serve as a dense inner encapsulation, enhancing both light (ISOS‐L‐1) and thermal (ISOS‐D‐2I) device stabilities. [ABSTRACT FROM AUTHOR]

Silicon oxide (SiO x) exhibits promising potential as a lithium-ion battery anode. However, its practical application is impeded by low electrical conductivity and significant volumetric expansion. To overcome these limitations, we developed a novel co-precipitation and selectively etching approach that leveraged the nitrogen-retaining effect of ZnNCN to prepare an edge-nitrogen-enriched carbon/SiO x composite (NEC@LC-SiO x). This NEC@LC-SiO x showed enhanced electrical conductivity and reduced volumetric expansion. Our innovative approach effectively prevented excessive decomposition of nitrogen species, resulting in a high nitrogen doping content of 21.67 at.% while maintaining a stable structure and mitigated volume expansion during charging and discharging. Consequently, the prepared NEC@LC-SiO x exhibited excellent performance as an anode material for lithium-ion batteries, demonstrating a high reversible specific capacity of 802 mAh/g and outstanding rate capability. This work presents a novel strategy for designing high-performance SiO x anode materials. [Display omitted] • The nitrogen-enriched lignin carbon/SiO x composite was synthesized as a anode material for lithium storage. • The nitrogen-enriched lignin carbon/SiO x composite had an ultrahigh N content of 21.67 at.%. • The nitrogen-enriched lignin carbon/SiO x composite exhibited a high specific capacity of 802 mAh/g. [ABSTRACT FROM AUTHOR]

Magnetic nanocomposite was prepared using the wet chemical precipitation approach with varying amounts of cobaltous oxide (CoO). The concentrations of CoO were 0.5, 3.5, 6.5, and 9.5 g per 100 % wollastonite composition. Samples were sintered separately at 1000 and 1200 °C. X-ray diffraction analysis (XRD) of the sintered parent sample revealed the formation of wollastonite CaSiO 3 and larnite Ca 2 SiO 4 , as well as a minor silicon oxide SiO 2 phase. In CoO-doped samples, Co-åkermanite Ca 2 CoSi 2 O 7 and other phases were formed. The XRD and scanning electron microscope SEM confirm the samples' submicron and nanocrystalline microstructure. The Fourier transform infrared spectroscopy (FTIR) and Raman spectra (RS) of investigated samples sintered at 1000 and 1200 °C revealed their bond structure. Both analyses confirmed that incorporating CoO into CaSiO 3 significantly improved its vibrational modes, reflecting structural modifications. By increasing the cobalt oxide content from 3.5 to 9.5 wt%, the samples attain the ideal paramagnetic state, as demonstrated by the magnetic hysteresis (M − H) curve, which is linearly reversible. Formation of the Ca 2 CoSi 2 O 7 significantly alters the magnetic characteristics of the samples, whether through increasing the cobalt oxide concentration up to 9.5 wt% or modifying the sintering temperature. This enables the prepared nonocomposites to be suitable for novel magnetic applications. [ABSTRACT FROM AUTHOR]

Atomic layer deposition (ALD) benefits from high process temperatures when the substrate is not temperature-sensitive because the films deposited at higher temperatures exhibit better electrical properties. In this study, we investigated the ALD process of silicon oxide films by alternating injections of tris(dimethylamino)silane (tris-DMAS) and O 3 /O 2 at temperatures ranging from 400 to 700 °C. The saturation dose of tris-DMAS was 1.5 × 106 L at 400 °C. Self-limiting growth with a growth rate of approximately 0.9 Å/cycle was observed up to 600 °C, allowing excellent step coverage. However, at 700 °C, the growth rate increased significantly to 4.6 Å/cycle, carbon and nitrogen impurities were detected by secondary ion mass spectrometry, and step coverage was poor, supporting the thermal decomposition of tris-DMAS at this temperature. Therefore, the optimum temperature for ALD SiO 2 using tris-DMAS is 600 °C for application as an insulating film on high aspect ratio patterns. At this temperature, the leakage current density was 0.58 nA/cm2, and the oxide-trapped charge density was 4.0 × 1010 cm−2. [ABSTRACT FROM AUTHOR]

Doping silicon wafers without using highly toxic or corrosive chemical substances has become a critical issue for semiconductor device manufacturing. In this work, ultra‐thin films of hydroxyapatite (Ca5(PO4)3OH) are prepared by tethering by aggregation and growth (T‐BAG), and further processed by spike annealing. Via in situ infrared (IR), the decomposition of hydroxyapatite and intermixing with the native silicon oxide is observed already at temperatures as low as 200 °C. Phosphate transport through the native silicon oxide is driven by a phase transformation into a more stable thermal oxide. At 700 °C, diffusion of phosphorus into the sub‐surface region of oxide‐free silicon is observed. In situ IR combined with electrical impedance spectroscopy (EIS), time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS), and X‐ray photoelectron spectroscopy (XPS) measurements allows to conclude that the phosphorus is: i) transported through the silicon oxide barrier, ii)) diffused inside the oxide‐free silicon, and iii) finally modified the electrical activity of the silicon wafer. To further explain the experimental findings, density‐functional theory (DFT) is used to demonstrate the extent of the effect of phosphorus doping on the electronic nature of silicon surfaces, showing that even small amounts of doping can have a measurable effect on the electrical performance of semiconductor wafers. [ABSTRACT FROM AUTHOR]

Herein, ex situ wet cleaning and in situ high‐temperature annealing of GaN surfaces prior to low pressure chemical vapor deposition (LPCVD) of the SiO2 gate oxide, aiming at effective SiO2‐GaN interface engineering for channel improvement of metal–oxide semiconductor (MOS) transistors, are investigated. Additionally, the combination of in situ annealing and gate oxide deposition in an LPCVD tool provides the advantage of an industrially preferred batch process. A strong impact of the pretreatments on the interface state density Dit$D_{\text{it}}$ and flatband voltage VFB$V_{\text{FB}}$ of the fabricated n‐type GaN MOS capacitors is demonstrated. Combined HF wet cleaning and NH3$_{3}$ annealing result in a low peak interface state density DitHF+NH3=1.5×1011 cm−2 eV−1$D_{\text{it}}^{\text{HF} + \left(\text{NH}\right)_{3}} = 1.5 \times \left(10\right)^{11} \textrm{ } \left(\text{cm}\right)^{- 2} \textrm{ } \left(\text{eV}\right)^{- 1}$ and a close to ideal C–V curve with a nearly ideal flatband voltage VFBHF+NH3=−0.1 V$V_{\text{FB}}^{\text{HF} + \left(\text{NH}\right)_{3}} = - 0.1 \textrm{ } \textrm{ } \text{V}$. Furthermore, the I–V characteristics exhibit a positive voltage shift of the current onset and substantially reduced I‐V hysteresis, i.e., negligible temporary charging. Physical root causes are assumed to be reduced contamination due to nondestructive yet efficient HF cleaning combined with subsequent high temperatures and the reduction of near‐interface, quasi‐permanent traps due to the saturation of dangling bonds by the annealing in hydrogen‐containing atmosphere. [ABSTRACT FROM AUTHOR]

Synthesis of porous ceramic materials based on fine SiC with sintering silicon oxide and magnesia binders at T = 800–1300 °C is considered. Special attention is paid to the influence of the shape and morphology of the initial powder particles on structural parameters and characteristics of porous ceramic materials. The SiC membranes sintered at 1000–1300 °C had average pore sizes of 0.5–1 μm, open porosity - up to 50 %, bending strength - up to 48.5 MPa and high water permeance - up to 7890 l⋅m−2⋅h−1⋅bar−1. The established filtration efficiency was ∼99 % in the case of screening out model particles of D 50 = 0.5 μm in size with maintaining stable permeance and physico-mechanical characteristics after multiple filtration-regeneration cycles. Comprehension of the initial powders morphology impact on the synthesized porous ceramics parameters makes it possible to forecast and ensure the preset structural, dimensional and physico-mechanical parameters of the materials under study properly. This work can be used for practical low-cost production of highly efficient SiC membranes for micro- and ultrafiltration processes, as well as base for catalysts. [ABSTRACT FROM AUTHOR]

In the realm of lubrication, nanoparticles play a pivotal role in enhancing the tribological efficacy of lubricating oils. Unveiling a critical need, the research underscores the necessity for a predictive model capable of anticipating these performance characteristics. This research endeavors to fill this gap by introducing an artificial neural network (ANN) tailored specifically for predicting the behavior of nanolubricants. The optimized neural network structure, at 5 × 8 × 2, attains a remarkable minimum mean square error of 0.00046667, with R-values hovering at impressive proximity to unity (0.99828). During the confirmation phase, the neural network's predictions demonstrate a deviation of 7.51% (negative) and 2.87% (negative) for COF, alongside 0.50% and 1.80% for WSD, further affirming its predictive capacity in assessing lubricant performance characteristics. [ABSTRACT FROM AUTHOR]

The study investigated the phase transformation and microstructural comparison of two types of continuous alumina fibers with varying silica contents. These fibers were subjected to heat treatment at temperatures of 1100, 1200, 1300, and 1400 °C in air. By comparing the experimental results of the two different fibers, relevant influencing mechanisms were derived. The appearance of mullite phase in the fibers occurred when the heat treatment temperature reached 1200 °C. Variations in silicon content led to inconsistent pinning effects, resulting in differences in the occurrence of irregular structures on the surface of the two types of fibers. Following heat treatment at 1300 °C, the fibers exhibited scale-like and mosaic-like structures, accompanied by phase aggregation. Subsequent heat treatment at 1400 °C resulted in the fibers displaying layered structures composed of α-Al 2 O 3 phase and undergoing significant changes in microstructure. Notably, the two types of fibers exhibited a significant difference in the presence or absence of a glass phase, and the addition of silicon oxide to a certain extent was found to inhibit the crystal transformation of Al 2 O 3. Additionally, the experimental results were analyzed in terms of influencing mechanisms based on theories such as activation energy barriers and total free energy. [ABSTRACT FROM AUTHOR]

Unfavorable environmental conditions pose a major barrier to sustainable agriculture. Among the various innovative strategies developed to protect plants from abiotic stress, the use of phytohormones and nanoparticles as "stress mitigators" has emerged as one of the most important and promising approaches. The objective of this study was to observe the protective role of melatonin (Mel) and silicon oxide nanoparticles (SiO-NPs) in rice (Oryza sativa L.) seedlings under cadmium (Cd) stress. Rice seedlings have reduced growth and phytochemical attributes when grown in Cd-contaminated (0.8 mM) pots. Seedlings under Cd stress had 38% less shoot length (SL), 53% total soluble sugar (TSS) and 57% protein content. However, superoxide dismutase (SOD), hydrogen peroxide (H2O2) and malondialdehyde (MDA) increased by 51%, 37% and 34%, respectively, under Cd stress. Beside this, activities such as peroxidase (POX) also elevated in the plants subjected with Cd-stress. In contrast, Mel (100 μm) as foliar spray and SiO-NPs (100 mg/L) as root dipping reduced oxidative stress in rice seedlings under Cd stress by reducing reactive oxygen species (ROS) generation. Furthermore, the application of Mel and/or SiO-NPs significantly increased the activity of antioxidative enzymes that scavenge ROS. The combined application of SiO-NPs and Mel increased growth, gas exchange and photosynthetic attributes, chlorophyll value, and protein content. It causes alleviation in the activity of SOD, CAT and POX by 73%, 62% and 65%, respectively. Overall, this study findings show that Mel and/or SiO-NPs can potentially protect the rice crop against oxidative damage under Cd stress. [ABSTRACT FROM AUTHOR]

Chemical reactivity of the superheavy elements nihonium (Nh, element 113) and moscovium (Mc, element 115) has been studied by the gas-solid chromatography method using a new combined chromatography and detection setup. The Mc isotope, 288Mc, was produced in the nuclear fusion reaction of 48Ca ions with 243Am targets at the GSI Helmholtzzentrum Darmstadt, Germany. After isolating 288Mc ions in the gas-filled separator TASCA, adsorption of 288Mc and its decay product 284Nh on silicon oxide and gold surfaces was investigated. As a result of this work, the values of the adsorption enthalpy of Nh and Mc on the silicon oxide surface were determined for the first time, … and … The obtained -ΔHads values are in good agreement with results of advanced relativistic calculations. Both elements, Nh and Mc, were shown to interact more weakly with the silicon oxide surface than their lighter homologues Tl and Bi, respectively. However, Nh and Mc turned out to be more reactive than the neighbouring closed-shell and quasi-closed-shell elements copernicium (Cn, element 112) and flerovium (Fl, element 114), respectively. The established trend is explained by the influence of strong relativistic effects on the valence atomic orbitals of these elements. [ABSTRACT FROM AUTHOR]

This study introduces a feasible approach for preparing Al2O3‐based ceramics with highly controllable performance via binder jetting. The Al2O3‐based ceramics were prepared using Al2O3 and H3BO3 as raw materials. The results showed that the samples prepared with 0.24 mol H3BO3 exhibited high apparent porosity (64%–66.67%), well‐bending strength (3.46–8.53 MPa), and low thermal conductivity (0.113–0.329 W·m−1·k−1 at 200–800°C). It was observed by an electron microscope that the increase of boric acid content led to the in‐situ formation of more aluminum borate grains in the sample. Meanwhile, the remaining Al2O3 reacts with silicon oxide in the impregnation solution to form mullite whiskers. The whiskers ensured that the sample had superior mechanical properties and lower thermal conductivities. Based on the above properties, the possibility of Al2O3‐based ceramics application in the aerospace field can be speculated. [ABSTRACT FROM AUTHOR]

Hybrid hole transport layers (HHTLs) consisting of‐a low‐cost, low‐temperature, dopant‐free, organic, hole‐selective poly(3,4‐ethylenedioxythiophene):polystyrene sulphonate (PEDOT:PSS) and an inorganic homogenous tunnel oxides (HoTOs), such as SiOx, TiOx, and AlOx have allowed significant improvements in carrier selectivity as well as in power and cost efficiency. These key parameters can be further improved by introducing heterogeneous tunnel oxides (HeTOs), formed of two different inorganic oxides. This work examines the potential of heterogeneous HHTLs and their impact on passivation as well as on the interfacial properties in silicon solar cells. HeTOs of SiOx/TiOx and SiOx/AlOx with negative fixed charge are studied and optimized. A heterogeneous HHTL with AlOx (>1.5 nm) resulted in a high lifetime (1.2 ms), low surface recombination velocity, and improved surface band bending at the interface due to the presence of higher negative fixed charge (1012 cm−2) within these layers. The passivation properties further improved on light soaking and annealing due to oxidation of PSS and AlOx/SiOx. Overall, these HHTLs demonstrated a hole selectivity (S10) of 12.5 and very high efficiencies up to of 26.1%, surpassing homogenous‐SiOx/PEDOT:PSS by 1.4%. [ABSTRACT FROM AUTHOR]

Silicon oxides (SiOx) have received extensive attention as a promising anode candidate for next‐generation lithium‐ion batteries (LIBs). However, their commercial applications have been seriously hindered by low conductivity, large volume expansion, and unstable solid‐electrolyte interface (SEI) layer, which result in low initial coulombic efficiency, poor rate performance, and short cycling lifespan. In this work, we demonstrated a simple way to prepare a series of SiOx materials with lithium fluoride (LiF) modified. When the mass ratio of SiOx and LiF equaled 1 : 0.15, the long‐term cycling capacity retention could be greatly improved from 30.1 % to 76.5 % after 300 cycles. The result was primarily because of the enhancement of electrons and Li+‐ions transport and the stability of the SEI layer due to LiF addition. However, excess LiF addition could hinder the diffusion of Li+‐ions. This study presented the great potential of LiF modified on SiOx anode materials for LIBs. [ABSTRACT FROM AUTHOR]

Here, a high-sensitivity silver-based surface plasmon resonance biosensor by a coating of zinc oxide on silicon for detecting hybridization of DNA is reported numerically. By changing the surface plasmon resonance angle and the minimum reflectance, this proposed biosensor can examine the difference between matched and mismatched DNA strands, as well as the nucleotide bonding between double-stranded (dsDNA) helix structures, and recognize the hybridization of target DNAs by using probe DNA immobilized on zinc oxide in the proper orientation. Also, the methodology of this work can detect single nucleotide polymorphisms (SNP). Using the transfer matrix method, we investigated the performance parameters of the biosensor. We observed that our proposed sensor has a maximum sensitivity of 378.36 deg/RIU and a good quality factor of 71.183 RIU−1. As we can see, compared with other reported papers, our proposed biosensor shows much better performance. This paper uses the biocompatibility, the electrical properties, the chemical stability, and high affinity of both Si and ZnO in surface plasmon resonance biosensors for the hybridization of DNA. [ABSTRACT FROM AUTHOR]

Glutathione (GSH), a thiol containing small peptide, plays pivotal roles in maintaining cellular redox balance, metabolism, detoxification, and scavenging of free radicals. Aberrant GSH levels in cells and tissues are associated with various disorders, underscoring the importance of accurate GSH detection for clinical diagnosis and therapy monitoring. Several molecular probes have been designed as fluorescent‐based GSH sensors. However, their water insolubility and the need of using organic cosolvents hinder their applicability on biological samples. Alternatively, nanomaterials have proven to be highly promising for boosting the precision of treatments and enhancing the accuracy of diagnosing diseases, thanks to their compatibility with biological environments and improved cell uptake. Here, the synthesis and characterization of a boron‐dipyrromethene (BODIPY)‐based probe (PB) are reported, incorporating a fluorescent BODIPY core, chlorine substituents for reaction with GSH, and a linking moiety for conjugation to the surface of silicon oxide nanoparticles (SONPs). Functionalized SONPs with PB are also characterized at the nanoscale using high‐resolution transmission electron microscopy (HR‐TEM), dynamic light scattering (DLS), Zeta potential, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), UV–Vis absorption, and fluorescence spectroscopies, confirming the surface functionalization and water‐dispersibility of functionalized SONPs with PB. GSH sensing is evaluated in aqueous solution, conjugated to SONPs, and in living cells, showing promising potential for ratiometric GSH detection. [ABSTRACT FROM AUTHOR]

With the rapid advancement of optical communication technology and integrated electronic devices, magneto-optical thin films, particularly rare earth iron garnet (RIG), have emerged as the most promising materials for near-infrared communication windows in recent years. In order to minimize the impact on the related properties of magneto-optical thin films during the preparation process, it's important to select the substrate materials. Silicon and garnet oxides are commonly used as substrates for the preparation of RIG magneto-optical thin films. The lattice constant of RIG magneto-optical thin films is generally around 12. 4 Å, and gallium-containing garnet oxide single crystal substrates have a similar lattice constant, which shows large lattice constant characteristics, making them one of the suitable substrate materials. However, the raw material gallium oxide is volatile at high temperature, the preparation of gallium-containing garnet single crystal has been a hot topic. The further study of gallium garnet series substrate single crystals is expected to promote the development of a new magnetooptical devices. In this paper, we reviewed the research of gallium garnet series single crystal, summarized the work of our team in the growth, structure and key parameters of these crystals, and outlooked the trend of research and development. [ABSTRACT FROM AUTHOR]

Silicon oxide (SiOx) coatings are attracting significant attention and are widely used in industrial applications. They can be prepared by plasma-assisted chemical vapor deposition (PACVD). PACVD at atmospheric pressure (AP-PACVD) is often employed to synthesize SiOx coatings, but it has generally not been scaled up to an industrially viable level. In the present work, a SiOx coating was continuously deposited onto a polyethylene terephthalate film using industrial-scale roll-to-roll type AP-PACVD. 1,1,3,3-Tetramethyldisiloxane (TMDSO) and tetraethoxysilane (TEOS) were selected as precursors. The elemental compositions and chemical structures of the SiOx coatings were characterized, and oxygen and water-vapor transmission rates were measured. The SiOx coating using TEOS exhibited better barrier properties than that using TMDSO, corresponding to the high oxygen content, high SiO2 content, and high siloxane network content in the SiOx coating. [ABSTRACT FROM AUTHOR]

Silicate minerals have a rich structural variety consisting of silicon oxide clusters or networks of any dimensionality interdispersed with different types of elements, which is reflected in marked changes in the Raman spectra. Understanding how the changes in the Raman spectra are correlated with the atomic structure would be highly desirable for fast material identification and analysis. Extracting such trends from experimental spectra can be difficult owing to the uncertainties in the structural details of the samples and in ensuring consistency between measurements from different sources. Simulated spectra, however, avoid these problems, making them a good candidate for systematic studies. Here, we study the correlation between the structure and Raman spectral features of 179 silicates derived from a database of Raman spectra simulated using first‐principles calculations. We investigate the spectral similarities with a specific emphasis on materials containing isolated 0D clusters in nesosilicate (SiO4), sorosilicate (Si2O7), and cyclosilicate (Si3O9 and Si4O12) configurations. While trends identified in the previous reports can be confirmed, we find that the variations within each group of similar structural motifs tend to be larger than the changes across groups, and therefore, developing a reliable automated classification algorithm is likely to be challenging. [ABSTRACT FROM AUTHOR]

A silicon photonics-based optical phased array (OPA) is promising for realizing solid-state and miniature beam steering. In our work, a 1 × 16 silicon optical phased array (OPA) hybrid integrated with a III–V laser is proposed and demonstrated. The III–V laser chip is vertically coupled with a silicon OPA chip based on a chirped grating coupler with a large bandwidth. The coupling efficiency reaches up to 90% through utilizing the metal reflector underneath the silicon oxide layer. The one-dimensional antenna array comprising silicon waveguides with half-wavelength spacing enables beam steering with none high-order grating lobes in a 180° field of view. The measured beam steering angle of the hybrid integrated OPA chip is ±25°, without grating lobes, and the suppression ratio of the side-lobes is larger than 9.8 dB with phase calibration. [ABSTRACT FROM AUTHOR]

As the core component of energy transfer in weapon system, safety and arming (S&A) devices affect the safety, reliability, and damage ability of the weapon. Micro-electromechanical systems (MEMS) S&A devices have been widely investigated for their smaller structure size, higher functional integration, and better smart functionality. This paper proposes the design of a multi-physics field-driven MEMS S&A device. The S&A mechanism is composed of a setback mechanism, a spin mechanism, and an electrothermal mechanism, achieving multiphysics-arming. With the coordination of the three mechanisms, the S&A device can produce a 1 mm displacement. The displacement generated allows the S&A device to switch between safety status and arming status. The unlock conditions and overload resistance of each mechanism are obtained by finite element simulation. Based on SOI wafers and silicon oxide wafers, the chips were fabricated and packaged. Several tests were carried out to verify the working condition and overload resistance of the S&A device. The result shows that under a voltage of 11 V and a rotation speed of 8000 r/min, with a size no more than 10 mm × 10 mm × 1.5 mm, the device works smoothly and can withstand an overload of 25,000 g. [ABSTRACT FROM AUTHOR]

This article presents the results of a thermodynamic analysis of the oxidation soda conversion reactions of minerals in ilmenite concentrates in the temperature range of 373–2273 K. The thermodynamic parameters of pseudorutile, pseudobrukite, and the new minerals, zhikinite and spessartine, were calculated for the first time. It has been established that the most important criterion relating to the stability of titanium minerals and related elements, as well as the reaction properties of the structural oxides of metals and silicon, is their degree of oxidation. Oxides of silicon (IV) and manganese have the best reactivity in solid-phase oxidizing alkaline environments (VI). Modeling this process scientifically substantiates the mechanism involved in the destruction of minerals in ilmenite concentrates in the low-temperature region in the presence of atmospheric oxygen and sodium oxide of soda ash, which are decomposed through the absorption of heat and the evaporation of moisture during the dehydration of hydrated minerals of iron and manganese and the dehydration of the soda–ilmenite batch. Tests conducted during pilot metallurgical production at the Institute of Metallurgy and Enrichment (PMP of JSC) confirmed the feasibility of processing high-chromium and siliceous rutile leucoxene ilmenite concentrates, which are unsuitable for traditional pyro- and hydro-metallurgical enrichment methods, through single-stage oxidation soda roasting, followed by the leaching of easily soluble sodium salts of iron and associated impurities with water and a dilute hydrochloric acid solution. The proposed energy-saving method ensures the production of high-purity (>98%) synthetic rutile while eliminating the formation of strong deposits on the lining of roasting units. [ABSTRACT FROM AUTHOR]

This study investigates the corrosion products present on TiSi, AlTi, and WTi coatings deposited onto Ti6Al4V titanium alloy substrates using the RF sputtering PVD technique. Following deposition, the coatings underwent exposure to a temperature of 600 °C for 100 h. The corroded surfaces were meticulously characterized to identify the resultant corrosion products. Utilizing scanning electron microscopy (SEM), X-ray diffraction, optical profilometry, and XPS spectroscopy, the coatings were comprehensively examined. Furthermore, Raman mapping with multivariate analysis was employed to determine the spatial distribution of oxides in the coating post-high-temperature corrosion. Additionally, XPS spectroscopy unveiled the presence of species undetected by Raman spectroscopy, such as silicon oxide SiO2, aluminum oxide Al2O3, and tungsten oxide WO2, in oxidation studies on TiSi, AlTi, and WTi coatings, corroborated by XRD analysis. The results allowed us to propose the corrosion mechanisms of these coatings and to determine that the TiSi coating exhibits a superior high-temperature corrosion response compared to the AlTi and WTi coatings. The AlTi coating experiences aluminum depletion, whereas the WTi coating shows accumulations of tungsten oxides that resemble pitting. [ABSTRACT FROM AUTHOR]

Introduction: Water limitation is one of the most important abiotic factors that can limit plant growth and yield due to production of reactive oxygen species (ROS) like H2O2 and the reduction of chlorophyll content. To protect against oxidative stress, plant cells produce both antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and peroxidase (POX), and non-enzymatic antioxidants such as low weight molecules like proline, sugars and ascorbate. Also water limitation disturbs the mineral-nutrient relations in plants through their effects on nutrient availability and numerous of physiological and biochemical destruction in the vegetative and reproductive periods of plant development. Several strategies have been suggested in order to improve yield under abiotic and biotic stresses in plants, among them application of Plant Growth Promoting Rhizobacteria (PGPR) and nano particles such as nano iron-silicon oxide play a key role in yield improvement. A better understanding of physiological responses under water limitation may help in programs which the objective is to improve the drouht resistance of crop. During the course of these stresses, active solute accumulation of compatible solutes such as proline and the activities CAT, POD and PPO enzymes are claimed to be an effective stress tolerance mechanism. Therefore, the aim of this study was to evaluate the effects of bio-fertilizers and nano iron oxide and nano oxide on some physiological and biochemical (i.e., antioxidant enzyme activity, chlorophyll, protein, soluble sugars and proline) responses of triticale under water limitation conditions. Materials and methods: An experiment was conducted as factorial based on randomized complete block design with three replicates at the research farm of faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili in 2021. The experimental factors were included of irrigation in three levels (full irrigation as control, irrigation withholding at 50% of booting and heading stages as severe and moderate water limitation respectively (BBCH 43 and 55 respectively), application of bio fertilizers in four levels (no application as control, application of Azospirilum, Pseudomonas, both application Azospirilum and Pseudomonas) and nanoparticles foliar application at four levels (foliar application with water as control, nano iron oxide foliar application (1 g.l-1), nano silicon oxide (50 mg.l-1), both application nano iron-silicon oxide). Psedomunas and Azospirilum were isolated from the rhizospheres of wheat by Research Institute of Soil and Water, Tehran, Iran. For inoculation seeds were coated with gum Arabic as an adhesive and rolled into the suspension of bacteria until uniformly coated. The strains and cell densities of microorganisms used as PGPR in this experiment were 1x108 colony forming units (CFU). In each plot there were 5 rows with 2 m long. In each experimental plot, two marginal rows and 0.5 m from beginning and ending of planting lines were removed data were measured from the middle lines. The used nano silicon-iron oxide had the average particle size less than 30 nm and special surface of particles was more than 30 m2.g-1. They were product of Nanomaterial US Research which was provided by Pishgaman Nanomaterials Company of Iran. Nano iron oxide and nano silicon powder added to deionized water and was placed on ultra sonic equipment (100 W and 40 kHz) on a shaker for better solution. Foliar application of nano silicon oxide and putrecine were done in two stages of period growth BBCH 21 and 30. Results and discussion: The results showed that total chlorophyll content (48.16%), quantum yield (36.05%), relative water content (35.83%) and grain yield (43.28%) increased in dual application of bio fertilizers and nano particles foliar application under full irrigation conditions compared to no application of bio fertilizers and nano particles under irrigation cut off at booting stage. But under such conditions, electrical conductivity, hydrogen peroxide and malondialdehyde content decreased 35.67, 53.16 and 56.32% respectively compared to no application of PGPR and nanoparticles under irrigation withholding in booting stage. Also, the application of PGPR and nanoparticles under irrigation cut off in booting stage increased the activity of catalase, peroxidase and polyphenol oxidase enzymes (47.06, 55.69 and 36.53% respectively), proline and soluble sugars content (45.41 and 46.93% respectively) compared to no application of PGPR and nanoparticles under full irrigation conditions. Conclusion: Based on the results of this study, the application of plant growth promoting rhizobacteria and nonoparticle can increase grain yield of triticale under water limitation conditions due to improving biochemical and physiological traits. [ABSTRACT FROM AUTHOR]

Due to the unique microstructure of hydrogenated nanocrystalline silicon oxide (nc‐SiOx:H), the optoelectronic properties of this material can be tuned over a wide range, which makes it adaptable to different solar cell applications. In this work, the authors review the material properties of nc‐SiOx:H and the versatility of its applications in different types of solar cells. The review starts by introducing the growth principle of doped nc‐SiOx:H layers, the effect of oxygen content on the material properties, and the relationship between optoelectronic properties and its microstructure. A theoretical analysis of charge carrier transport mechanisms in silicon heterojunction (SHJ) solar cells with wide band gap layers is then presented. Afterwards, the authors focus on the recent developments in the implementation of nc‐SiOx:H and hydrogenated amorphous silicon oxide (a‐SiOx:H) films for SHJ, passivating contacts, and perovskite/silicon tandem devices. [ABSTRACT FROM AUTHOR]

Pursuing improved electrode materials is essential for addressing the challenges associated with large-scale Li-ion battery applications. Specifically, silicon oxide (SiOx) has emerged as a promising alternative to graphite anodes, despite issues related to volume expansion and rapid capacity degradation. In this study, we synthesized carbon-coated SiOx using diatom biomass derived from artificially cultured diatoms. However, the inherent carbon content from diatoms poses a significant challenge for the electrochemical performance of diatom-based anodes in large-scale applications. Subsequently, we conducted further research and demonstrated excellent performance with a carbon content of 33 wt.% as anodes. Additionally, real-time characterization of the carbonization process was achieved using thermogravimetry coupled with infrared spectroscopy and gas chromatography mass spectrometry (TG-FTIR-GCMS), revealing the emission of CO and C3O2 during carbonization. Furthermore, electrochemical tests of the processed diatom and carbon (PD@C) anode exhibited outstanding rate capability (~500 mAh g−1 at 2 A g−1), high initial Coulomb efficiency (76.95%), and a DLi+ diffusion rate of 1.03 × 10−12 cm2 s−1. Moreover, structural characterization techniques such as HRTEM-SAED were employed, along with DFT calculations, to demonstrate that the lithium storage process involves not only reversible transport in Li2Si2O5 and Li22Si5, but also physical adsorption between the PD and C layers. Exploring the integration of diatom frustules with the intrinsic carbon content in the fabrication of battery anodes may contribute to a deeper understanding of the mechanisms behind their successful application. [ABSTRACT FROM AUTHOR]

The possibility of isovalent substitution of zinc and cobalt atoms in the structure of willemite Zn2SiO4 was studied. Ceramic pigments with a willemite structure of blue, violet, and light blue colors were synthesized. Samples of blue color were used in the manufacture of glazes. During the synthesis of the pigments, synthetic silicon oxide was replaced by natural quartz sand. The pigments were synthesized by solid-state method at a temperature of 1270°C. The physical and chemical properties of the synthesized blue pigment were determined. In addition, the pigment was tested for use in traditional glazes for the coloring of ceramic products. It was established that the obtained blue pigment provides high aesthetic and decorative characteristics at a relatively low price. [ABSTRACT FROM AUTHOR]

This work reports the fabrication of a Silicon Oxide (SiOx) thin film (TF) via an electron beam evaporator on an Indium Tin Oxide (ITO) substrate for the application of a non-volatile memory device. The TF exhibits a high transmittance of ~ 79.7% in the visible range. The presence of capacitive memory was analyzed for the frequency range from 500 kHz to 1 MHz. An interface trap density of ~ 5.47 × 1011 eV−1 cm−2 was estimated at 1 MHz. In addition, the charge trapping density per unit area was ~ 1011 cm−2 at ± 9 V. Furthermore, the fabricated device's resistive switching (RS) analysis revealed a butterfly-shaped bipolar and forming-free behavior. The device exhibits a good retention time of up to 104 s and a stable endurance for 1000 repeated switching cycles. The conduction mechanisms: Ohmic conduction and Space Charge Limited Current conduction were responsible for the RS mechanisms in the fabricated device. The outcomes of our study suggest that the Au/SiOx/ITO TF device can be a promising candidate for integration into next-generation transparent, non-volatile memory devices. [ABSTRACT FROM AUTHOR]

Nano- and micro-carriers of therapeutic molecules offer numerous advantages for drug delivery, and the shape of these particles plays a vital role in their biodistribution and their interaction with cells. However, analysing how microparticles are taken up by cells presents methodological challenges. Qualitative methods like microscopy provide detailed imaging but are time-consuming, whereas quantitative methods such as flow cytometry enable high-throughput analysis but struggle to differentiate between internalised and surface-bound particles. Instead, imaging flow cytometry combines the best of both worlds, offering high-resolution imaging with the efficiency of flow cytometry, allowing for quantitative analysis at the single-cell level. This study focuses on fluorescently labelled silicon oxide microchips of various morphologies but related surface areas and volumes: rectangular cuboids and apex-truncated square pyramid microchips fabricated using photolithography techniques, offering a reliable basis for comparison with the more commonly studied spherical particles. Imaging flow cytometry was utilised to evaluate the effect of particle shape on cellular uptake using RAW 264.7 cells and revealed phagocytosis of particles with all shapes. Increasing the particle dose enhanced the uptake, while macrophage stimulation had minimal effect. Using a ratio particle:cell of 10:1 cuboids and spheres showed an uptake rate of approximately 50%, in terms of the percentage of cells with internalised particles, and the average number of particles taken up per cell ranging from about 1–1.5 particle/cell for all the different shapes. This study indicates how differently shaped micro-carriers offer insights into particle uptake variations, demonstrating the potential of non-spherical micro-carriers for precise drug delivery applications. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to the low-temperature synthesis of cobalt-containing diopside pigments based on granulated blast furnace slag and to study the characteristics of the mineral formation processes, changes in the structure and colour indices. Design/methodology/approach: Synthesis of cobalt-containing diopside pigments based was carried out by the directional formation of the mineralogical composition with the introduction of part of the components using granulated blast-furnace slag. Findings: It has been established that the formation of the diopside phase in pigments containing blast-furnace slag as the main component proceeds at low temperatures (1,100°C–1,150 °C). The colour of diopside pigments is formed because of the isomorphic substitution of Si4+ ions for Al3+ ions and Mg2+ ions for Co2+ ions. It is expedient to add CoO in an amount of 0.9 mol (18 Wt.%) into the composition of diopside pigments based on blast-furnace slag to obtain defect-free violet glazes. Practical implications: The developed diopside pigments enable obtaining of high-quality violet glazes for ceramics. The application of the obtained results can significantly reduce the consumption of traditional raw materials in the composition of silicate ceramic pigments, as well as reduce their firing temperature. Originality/value: Calcium, magnesium and silicon oxides are the main components of blast-furnace slag. In addition, granulated blast furnace slag is mainly represented by the glassy phase, which determines its high activity during the firing process. These factors are prerequisites for using the blast-furnace slag as a valuable substitute for chemically pure or natural raw materials in silicate pigments and reducing their firing temperature. [ABSTRACT FROM AUTHOR]

[Display omitted] Silicon (Si) has gained substantial interest as a potential component of lithium-ion battery (LIB) anodes due to its high theoretical specific capacity. However, conventional methods for producing Si for anodes involve expensive metal reductants and stringent reducing environments. This paper describes the development of a calcium hydride (CaH 2)–aluminum chloride (AlCl 3) reduction system that was used for the in-situ low-temperature synthesis of a core–shell structured silicon–carbon (Si–C) material from rice husks (RHs), and the material was denoted RHs-Si@C. Moreover, as an LIB anode, RHs-Si@C exhibited exceptional cycling performance, exemplified by 90.63 % capacity retention at 5 A g−1 over 2000 cycles. Furthermore, the CaH 2 –AlCl 3 reduction system was employed to produce Si nanoparticles (Si NPs) from RHs (R-SiO 2 , where SiO 2 is silica) and from commercial silica (C-SiO 2). The R-SiO 2 -derived Si NPs exhibited a higher residual silicon oxides (SiO x) content than the C-SiO 2 -derived Si NPs. This was advantageous, as there was sufficient SiO x in the R-SiO 2 -derived Si NPs to mitigate the volumetric expansion typically associated with Si NPs, resulting in enhanced cycling performance. Impressively, Si NPs were fabricated on a kilogram scale from C-SiO 2 in a yield of 82 %, underscoring the scalability of the low-temperature reduction technique. [ABSTRACT FROM AUTHOR]

Silicon oxides (SiO, SiO2) with high theoretical capacity and low cost are viewed as promising anodes for the next‐generation lithium‐ion batteries (LIBs) but suffer from inferior rate capability and coulombic efficiency (CE) owing to the sluggish charge transfer kinetics. Herein, the study proposes a multichannel modulation strategy induced by ZSM‐5 and SiO as well as electron‐rich graphene to effectively solve the above issue. Specially, the ZSM‐5, which can not only provide a certain Li+ reserve capacity as an anode material, but also serve as a bridge to connect the isolated SiO nanoparticles, providing Li+ transport channel and adjusting the transfer kinetic, making it to achieve two things at one stroke, so that the as‐obtained SiO@ZSM@Gra composite shows improved rate performance and CE compared to that of single silicon oxides. Combing with the CV and EIS fitting analysis, it is demonstrated that the constructed composites own higher Li+ diffusion coefficient and more charge conduction capability. Furthermore, the fabricated full cell with LiNi0.8Co0.1Mn0.1O2 exhibits good electro‐chemical properties. The proposed strategy for intrinsic accelerating charge transfer can be conductive to electrode design for the next‐generation low cost and high energy LIBs. [ABSTRACT FROM AUTHOR]

Device scaling for future semiconductor technologies is driving the adoption of innovative methods for miniaturizing semiconductor chips. One promising approach that has garnered significant interest for sub-10 nm device scaling is area selective deposition (ASD). In this study, we demonstrate the feasibility of ASD of silicon dioxide (SiO2) on –OH terminated surfaces (silicon oxide: SiOx) but not on –NH terminated surfaces (silicon nitride: SiNx) for 2D blanket, 2D patterned, and 3D stacks using a novel precursor: Orthrus. To achieve this, we optimized the SiOx and SiNx layers to enhance the –OH and –NH surface bonds, respectively. Using x-ray photo spectroscopy analysis, we showed that SiO2 selectively deposits on SiOx without any nucleation delay compared to SiNx. We have demonstrated the inherent selective deposition of approximately ∼4 nm on 2D patterned structures and ∼3.7 nm on 3D stacks by fine-tuning the atomic layer deposition process. This selective thickness is >250% compared to a previously shown selective SiO2 deposition process in the literature. Finally, we also showed that the step coverage of selective SiO2 growth in 3D stacks is ∼1. This study highlights the potential pathway for performing ASD of commonly used SiO2 in 3D high-aspect-ratio stacks. [ABSTRACT FROM AUTHOR]

Gas separation is the process of separating primary gaseous components from the composition of air. The separated primary gaseous components are essential for many industrial purposes such as chemical, medical, aeronautical, food processing industries. Oxygen enriched air plays a crucial role in the fuel combustion process and medical applications. Membrane technology emerges in the field of gas separation due to its inherent multidirectional characteristics. The multilayer composite polymeric membrane has been developed using electrospun web, nonwoven substrate and casting polymer solution to improve the permeability and selectivity of oxygen gas molecule from the gas mixture. This membrane also consists of polyethylene glycol (PEG) and SiO2 nanoparticles which are used to improve the permeability and selectivity of oxygen molecules. Box- Behnken design has been wielded for the membrane construction by three independent variables such as volume of electrospinning solution (mL), Casting Solution (mL) and PEG concentration (%). Oxygen separation is carried out using the gas separation unit and it is constructed based on the principle of air separation. To analyze the performance of the developed membrane, the purity of oxygen from the composite membrane is estimated by a GC-MS. Mass per unit area and thickness of all membrane samples has been tested. From the results, the electrospun web thickness and casting solution concentration directly influence the oxygen purity and air separation rate. SiO2 nanoparticles are added to the casting solution and the electrospun web. The presence of SiO2 in the top and bottom layer of the membrane is used to attract the O2 molecules. Maximum oxygen purity was obtained from the membrane which has an electrospun web with 6mL and 30% casting solution with 2% PEG. From this flat sheet composite membrane, the purity range of oxygen is 42.2% with moderate permeability flux. [ABSTRACT FROM AUTHOR]

Scalable wet high-energy ball milling was used to refine commercial micro-silicon (Si) with water and ethanol as process control agents (PCA). After grinding, the original particle size of 15 microns was reduced to approximately 1 micron for both PCAs. The sample with water as PCA produced more amorphous silicon oxide on the surface of Si particles compared to ethanol, resulting in relatively inferior electrochemical performance. This is attributed to the fact that the water-milling-induced amorphous layer comprises a significant portion of high-valence Si than the ethanol-milling-induced surface layer. Various silicon powders ground with ethanol at different ratios (e.g., 1:3, 1:4, 1:9, and 1:12) were evaluated to establish process–performance relationships. The ball-milled Si powders with a silicon-to-ethanol ratio of 1:9 showed the best electrochemical performance, displaying an initial coulombic efficiency of about 90% and a reversible specific capacity of 3000 mA h/g for the first cycle. After 55 cycles, the reversible specific capacity was maintained at 2200 mA h/g at 0.105 A/g with a corresponding retention rate of 86%, showing good cycling stability. This amorphous shell layer structure introduced through the in situ surface during the grinding process played a role in boosting the electrochemical performance of the micro-silicon anode. In addition, the amorphous shell formed by SiOx on the milled micro-Si surface and its effect on the electrochemical performance are discussed in this paper. [ABSTRACT FROM AUTHOR]

Today, providing clean water is a significant need and challenge. Among the hazardous contaminants in raw water is the presence of heavy metals such as Pb(II) and Cu(II)). The Fe3O4/SiO2/PEG composite material was prepared by wet mixing; in this case, the Fe3O4 and SiO2 magnetic particles were prepared from iron sand and silica sand by the co-precipitation method, respectively. Polyethylene Glycol (PEG- 4000) acts as a binder and a matrix. The structural, surface, and magnetic characteristics of the nanosized adsorbent were investigated by elemental analysis, FTIR, N2 adsorption--desorption, transmission electron microscopy, powder X-ray diffraction, vibrating sample magnetometry, and zeta-potential measurement. The Fe3O4/SiO2/PEG composite exhibited high adsorption affinity for aqueous Cu(II), and Pb(II) ions. According to isothermal and kinetic analyses, adsorption follows the Langmuir isotherm model and the pseudo second order kinetic model based on the Langmuir isotherm model, the maximum adsorption capacities of Pb(II) and Cu(II) were 76.3 mg/g and 45 mg/g for the Fe3O4/SiO2/PEG composite with a mass ratio of Fe3O4/SiO2 of 1:1, respectively. The Fe3O4/SiO2/PEG (1:1) showed high adsorption capacity after three regeneration cycles (79%), which can be a potential magnetic adsorbent for wastewater treatment. [ABSTRACT FROM AUTHOR]

Traditional porcelain tiles often lack self-cleaning properties and suffer from aesthetic limitations. This study presents a novel approach for fabricating superhydrophobic, self-cleaning porcelain tiles with enhanced visual appeal. We strategically combined SiO2 and ZnO nanolayers with an antifouling material, applied via spray and drop coating methods. Characterizations (FE-SEM, FTIR, contact angle, UV-Vis, colorimetry, roughness, illuminance, and stain resistance) confirmed the effectiveness of our approach. Heat treatment of the antifouling coating (400 °C) significantly increased hydrophobicity (WCA=119°). SiO2 and ZnO intermediate layers enhanced water repellency, achieving 154° and 149° water contact angles, respectively. This demonstrates superhydrophobicity, in line with Cassie-Baxter's model, and mimics the lotus leaf's self-cleaning mechanism. Low surface energy, likely due to antifouling nanoparticle bonds, contributes to water repellency with roll-off angles of 6° and 7° and causes anti-stain properties on the tile surface. Importantly, these layers optimize surface roughness, boosting hydrophobicity and improving the whiteness and brightness of polished tiles. Surface roughness values of 308 nm (SiO2) and 158 nm (ZnO), along with superior whiteness values (116.4 and 106, respectively), were observed, exceeding surfaces without intermediate layers (57.5). Rayleigh scattering theory explains the whiteness enhancement. Stain resistance significantly improved with intermediate layers, while surface gloss remained unchanged. This research demonstrates the potential of our coating approach to create highly functional and visually appealing polished tiles for diverse industrial applications. [ABSTRACT FROM AUTHOR]

In the search for the optimization of heat transfer systems, ionanocolloids (INCs) which are suspensions of nanoparticles (NPs) in ionic liquids (ILs), have revealed as very attractive choices due to their increasingly potential applications in thermal energy areas. Besides a high degree of versatility and enhanced thermophysical properties, these new class of fluids are considered as green solvents due to their negligible vapor pressure, non-flammability and recyclability. Despite the great advantages of using these INCs, their industrial application is still a challenge due to low stability and high viscosity issues attributed to them. In this work, different INCs were prepared by two-step method, using 1-ethyl-3-methylimidazolium dicyanamide ([C2mim][DCA]) mixed with deionized water (DW) as base fluids and 3 different NPs: Titanium(IV) Oxide, Silicon Oxide and Aluminum Oxide. Stability was evaluated through visual inspection. Viscosity of stable INCs was determined over different temperatures and shear rates, and electrical conductivity was measured. [ABSTRACT FROM AUTHOR]

In this study, a novel periodic multilayered DLC coating, which was composed of a Si interlayer and a Si/N co-incorporated DLC layer (Si/(Si, N)-DLC) per period, was deposited; the corrosion behavior under the neutral, acidic, or alkaline coal mine water environment and its periodic number dependence, especially the fundamental corrosion mechanism, were systemically explored. Results suggest that compare to the substrate, the introduction of multilayered Si/(Si, N)-DLC coating presents a dramatic enhancement in the corrosion resistance under coal mine water environment. However, with increasing the periodic number, the corrosion resistance of the multilayered coating strongly depends on the working environment, which exhibits an enhancement in neutral and alkaline environments while a degeneration in acidic environment. This is attributed to not only the prolongation of the corrosion path caused by the multilayered structure but also the formation of an insulating silicon oxide layer in neutral and alkaline environments. However, in acidic environments, the strong permeability of H+ with the smallest ionic radius easily infiltrates the inherent defects of the coating. This not only weakens the protective properties of the multilayer structure but also leads to hydrogen-induced cracking, ultimately diminishing corrosion resistance. These findings theoretically guide the development of the DLC coatings with excellent corrosion resistance for coal mine applications. [ABSTRACT FROM AUTHOR]

In this paper, two new silicon on insulator metal-semiconductor field effect transistor (SOI-MESFET) structures are presented. Two parallel layers of oxide and aluminium are added at the gate edge of these structures. Also, in the buried oxide part of the Aluminium Edge and Silicon-Well MESFET (AESW-MESFET) structure, a silicon well and two aluminium layers are added. Moreover, and to improve the DC and RF characteristics, as compared to the Conventional MESFET (C-MESFET) structure, a silicon well and a silicon layer are added in the box oxide section in the Silicon Edge and Silicon-Well MESFET (SESW-MESFET) structure. By these changes, the value of the breakdown voltage in the normal structure has increased from 15.8 V to 33.1 V and 30.9 V in the proposed AESW-MESFET and SESW-MESFET structures, respectively. In addition, the maximum output power has been associated with a significant increase of 4.44 and 5.24 times, respectively. Compared to the C-MESFET, the proposed structures reduce gate-source and gate-drain capacitors and significantly increases conductivity. The cut-off frequency values are increased from 19.3 GHz (the normal structure) to 37.3 GHz and 35 GHz (the proposed structures), and the maximum oscillation frequencies are increased from 80 GHz to 154 GHz and 102.3 GHz. Therefore, the results show that the proposed structures have good performance and the ability to work at high power and high frequency. [ABSTRACT FROM AUTHOR]

The high shrinkage of metakaolin-based geopolymers (MKGs) dramatically limits their application as high-performance green cementitious materials. In this study, microscopic tests and microstructure analysis of the polymerization reaction products are employed to examine the drying shrinkage properties of MKG under different alkali equivalents. The results indicate an enhancement in the strength of MKG mortar with increasing alkali equivalent; however, it undergoes shrinkage in the later stages. Notably, the drying shrinkage increases with the alkali equivalent, mainly attributed to the fact that the increase in alkali equivalent does not change the types of hydration products in MKG. Instead, it promotes the dissolution of active silicon oxide and alumina in metakaolin (MK) particles, accelerating the hydration reaction process and, resulting in a higher amount of sodium aluminosilicate hydrated gel (N─ A─ S─ H) gel. Furthermore, the alkali equivalents modify the pore size distribution, leading to an increase in the 10–50-nm pore volume and capillary negative pressure, ultimately causing an increase in drying shrinkage. [ABSTRACT FROM AUTHOR]

This paper compares the thermal behavior of Ethylene Glycol (EG) and nano particles of Al2SiO5 immersed water based cutting fluid as coolants experimentally for the application of radiator used in automobile. In this regard, forced convective heat transfer coefficient has been equated for base fluid i.e. EG and water-based nanoparticles (NPs) of Al2SiO5 immersed nanofluids (NFs). For NFs, nano particles of Al2SiO5 have been mixed at concentration of 0.1%, 0.2%, 0.3% and 0.4% considering the vol% /vol%. The base fluid has been prepared by mixing the 40% EG and 60% pure water based on vol% / vol%. To have a laminar flow, all the experiments have been performed for Reynolds number ranging from 500 to 1500. For all experimental trials, the NFs were allowed to flow across the tubes of radiator made in elliptical cross section. Besides, the air is allowed to pass at constant speed in the direction of perpendicular to the flow of coolant at the passage between the tube bundles. The obtained experimental results suggest that the increment in flow rate can enhance the heat transfer. However, negligible impact has been observed for the change in inlet temperature of radiator. The increment in heat transfer upto 47% has been observed when NPs having low concentration has been immersed in base fluid. To compare the heat transfer, a non-dimensional coefficient of heat transfer i.e. Nusselt Number (Nu) has been calculated. [ABSTRACT FROM AUTHOR]

Pulsed lasers are a powerful tool for fabricating silicon carbide (SiC) that has a hard and brittle nature, but oxidation is usually unavoidable. This study presents an exploration of the oxidation mechanism of 4H–SiC in oxygen and water under different temperatures via reactive force field molecular dynamics. Single pulse irradiation experiments were conducted to study the oxygen content of the laser-affected zone through energy dispersive x-ray spectrometry. The results show that laser-induced thermal oxidation is a complex dynamic process with the interactions among H, C, O, and Si atoms. The oxidation zone includes an oxide layer, a graphite layer, and a C-rich layer. With an increase in oxygen concentration, the amorphous oxide layer changes from silicon oxide to silicon dioxide. In addition, the formation of carbon clusters at the interface between SiOx and C-rich layers promotes the desorption of the oxide layer. The mechanism revealed in this study provides theoretical guidance for high-quality processing of 4H–SiC at atomic and close-to-atomic scales. [ABSTRACT FROM AUTHOR]

Background. Phytobiotic additives and ultrafine particles (UFP), especially of metallic nature, are increasingly used in agriculture as fertilizers and components of feed additives. However, there is very little data about the effect of non-metallic UFP. In particular, silicon-containing UFP have shown high efficiency as plant growth stimulators under stress conditions, but whether they can act as antibacterial agents or as protective agents in microbial ecosystems is unknown. Therefore, the aim of the presented work is to evaluate positive and negative reactions of the model luminescent microorganism Escherichia coli K12 TG1 when exposed to suspensions of silicon IV oxide (SiO2) in various concentrations both in pure form and in combination with phytobiotic additive – oak bark extract. Materials and methods. The luminescence intensity of the recombinant strain of Echerichia coli of the natural marine microorganism Photobacterium leiongnathi with cloned luxCDABE-genes under the influence of concentrations (0.5-0.00024 M) of UFP SiO2 and aqueous extract of oak bark (2-1024 multiples) was studied. Results. It was found that UFP in pure form stimulate bacterial luminescence by 252.2 % with respect to the control in the stationary phase of growth at 0.5 mol/L. They also act as protectors of intracellular metabolism, reducing the inhibitory effect of oak bark extract. The latter in pure form suppresses more than 50 % of bacterial luminescence up to 4-fold dilution (12.5 mg/mL), which determines the possibility of its use as an alternative to antibiotic drugs. Conclusion. UFP SiO2 have pronounced protective properties with respect to microbial community.

A highly transparent passivating contact (TPC) used for high‐efficiency crystalline silicon (c‐Si) solar cells should meet several key criteria: high optical transparency, excellent c‐Si surface passivation, low contact resistivity, and a low‐temperature fabrication process suitable for device integration. Here, a simple TPC is developed structure consisting of a silicon oxide (SiOx) tunneling passivating layer and an aluminum doped zinc oxide (AZO) electron‐selective transporting layer (SiOx/AZO). This TPC demonstrated remarkable passivation quality with a low contact recombination current density of below 2.2 fA cm−2, an implied open‐circuit voltage of close to 740 mV and a contact resistivity below 20 mΩ·cm2 when contact with lightly doped n‐type c‐Si. This excellent passivation performance can be attributed to improved interfacial hydrogen chemical passivation and the field‐effect passivation induced by the highly Al‐doped ZnO film. Demonstrated n‐type c‐Si solar cells using full‐area SiOx/AZO rear contacts achieved a significant efficiency of 23.17%. Further power loss analysis based on numerical simulations outlines the pathway to achieving efficiencies exceeding 26%. [ABSTRACT FROM AUTHOR]

Perovskite‐oxide‐based ferroelectric tunnel junctions (FTJs) hold great potential for applications in non‐volatile memory and neuromorphic computing due to their unique properties. However, the challenges in synthesizing high crystalline quality perovskite oxides directly on silicon wafer limit the applications of these FTJs in conventional Si‐based integrated circuits, let alone the neural networks. Herein, perovskite oxide FTJs with an ON/OFF ratio up to 1.2×106, writing/erasing speed down to 1 nanosecond, and cycling endurance (>106) are achieved by integrating ultrathin freestanding ferroelectric perovskite oxide membranes directly on silicon wafers using a wet‐transfer method. Moreover, synapses based on these FTJs exhibit long‐term plasticity. For handwritten digits recognition task, the convolutional neural network (CNN) simulation is implemented achieving a recognition accuracy up to 98.9% based on the experimental performance, close to the result of 99.2% by software‐floating‐point‐based CNN. This work sheds light on the integration of ferroelectric perovskite oxides directly on silicon for high‐performance FTJ‐based non‐volatile memory and synaptic devices. [ABSTRACT FROM AUTHOR]

The anisotropic dependence of the velocity of surface acoustic waves (SAW) on silicon is explored using surface Brillouin light scattering. Measurements of the SAW velocity are compared to a numerical model that takes into account the native thin amorphous oxide layer formed at the top surface of the silicon wafer. The model accounts for material loss and provides a relative estimate for the backscattered intensity resulting from the ripple effect. For the (100) sample considered, a thickness of 4 nm fits well with experimental data, considering material constants of amorphous silica for the oxide. A global phase velocity decrease of −11 m/s per nanometer of silica thickness is predicted for surface phonons at frequencies around 16 GHz. [ABSTRACT FROM AUTHOR]

This study introduces silicon substrates with a switchable magnetic contrast layer (MCL) for polarized neutron reflectometry (PNR) experiments at the solid–liquid interface to study soft‐matter surface layers. During standard neutron reflectometry (NR) experiments on soft‐matter samples, structural and compositional information is obtained by collecting experimental data with different isotopic contrasts on the same sample. This approach is normally referred to as contrast matching, and it can be achieved by using solvents with different isotopic contrast, e.g. different H2O/D2O ratios, and/or by selective deuteration of the molecules. However, some soft‐matter systems might be perturbed by this approach, or it might be difficult to implement, particularly in the case of biological samples. In these scenarios, solid substrates with an MCL are an appealing alternative, as the magnetic contrast with the substrate can be used for partial recovery of information on the sample structure. More specifically, in this study, a magnetically soft Fe layer coated with SiO2 was produced by ion‐beam sputter deposition on silicon substrates of different sizes. The structure was evaluated using X‐ray reflectometry, atomic force microscopy, vibrating sample magnetometry and PNR. The collected data showed the high quality and repeatability of the MCL parameters, regardless of the substrate size or the thickness of the capping SiO2 layer. Previously proposed substrates with an iron MCL used an Au capping layer. The SiO2 capping layer proposed here allows reproduction of the typical surface of a standard silicon substrate used for NR experiments and is compatible with a large variety of soft‐matter samples. This application is demonstrated with ready‐to‐use 50 × 50 × 10 mm substrates in PNR experiments for the characterization of a lipid bilayer in a single solvent contrast. Overall, the article highlights the potential of PNR with an MCL for the investigation of soft‐matter samples. [ABSTRACT FROM AUTHOR]

The high silicon content in rice plant waste, specifically rice husks, makes this waste by-product attractive for the extraction and valorization of silicon oxide, which is widely used as an inert support in catalysis, drug delivery and molecular sieving. The procedures currently used for the treatment of plant biomass make extensive use of mineral acids (HCl, H2SO4, HNO3), which, besides them being potential environmental pollutants, reduce the yield and worsen the chemical-physical properties of the product. In this study, an evaluation of the easy treatment of rice husks by benchmarking different, more eco-friendly carboxylic acids in order to obtain a mesoporous SiO2 with an alveolar structure and a relatively high surface area and pore volume (300–420 m2/g, 0.37–0.46 cm3/g) is presented. The obtained mesoporous silicas are characterized by worm-like pores with a narrow size distribution and a maximum in the range of 3.4–3.5 nm. The mesoporous structure of the obtained materials was also confirmed by TEM. The complete removal of the organic part of the rice husks in the final materials was evidenced by thermogravimetric analysis. The high purity of the obtained mesoporous silica was detected using ICP analysis (98.8 wt. %). The structure peculiarities of the obtained mesoporous silicas were also characterized by solid-state NMR and ATR-FTIR spectroscopies. The morphology of the mesoporous silica was investigated by SEM. [ABSTRACT FROM AUTHOR]