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The ability to utilize a hybrid-photon-counting detector to its full potential can significantly influence data quality, data collection speed, as well as development of elaborate data acquisition schemes. This paper facilitates the optimal use of EIGER2 detectors by providing theory and practical advice on (i) the relation between detector design, technical specifications and operating modes, (ii) the use of corrections and calibrations, and (iii) new acquisition features: a doublegating mode, 8-bit readout mode for increasing temporal resolution, and lines region-of-interest readout mode for frame rates up to 98 kHz. Examples of the implementation and application of EIGER2 at several synchrotron sources (ESRF, PETRA III/DESY, ELETTRA, AS/ANSTO) are presented: high accuracy of high-throughput data in serial crystallography using hard X-rays; suppressing higher harmonics of undulator radiation, improving peak shapes, increasing data collection speed in powder X-ray diffraction; faster ptychography scans; and cleaner and faster pump-and-probe experiments. [ABSTRACT FROM AUTHOR]

One function of plant Si is ameliorating stress, including drought and salinity stress, which can induce active Si uptake in addition to passive uptake via transpiration. However, the interactions and feedbacks between stress, water movement and Si uptake remain unknown.To examine this gap, we compiled papers reporting transpiration and/or stomatal conductance of plants exposed to stresses while varying Si availability.Our meta‐analysis (34 studies, excluding rice) showed that stress alters the role of Si in controlling water movement across diverse plant groups. Increased Si availability significantly increased water movement in stressed plants, particularly stomatal conductance (p < 0.001, k = 84) in plants exposed to salinity (p < 0.05, k = 20) and drought (p < 0.05, k = 45) stress.This signal of increased conductance was most apparent in C4 plants (p < 0.001, k = 41) and Poales (p < 0.001, k = 47). These findings have implications for plants under increasing water and salinity stress, particularly for Poales, where survival in affected ecosystems could be mediated by soil Si availability, and in agricultural systems, supplying Si to water‐stressed plants could increase productivity.Intriguingly, Si addition to unstressed plants had no consistent impact on water movement, with reduction of water movement with Si addition to unstressed plants in 50% of studies, mostly those involving non‐Poales species. This is an important first broad‐scale Si cost quantification, as the costs of Si for plants have remained stubbornly mysterious, hampering evolutionary and functional understanding of plant Si use. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

As a key element of the silicon growth furnace, the heating power supply plays an important role to form the required thermal field for mono‐silicon growth. The performance of the heating power supply system is critical to implement the function, which is determined by both hardware topology and control strategies. In this paper, a novel two‐stages soft‐switching power supply topology is employed to improve the efficiency of the power supply system. Meanwhile, the robust control methods are proposed for both stages converter to achieve high power factor (PF), low total harmonic distortion (THD) and stable output DC voltage under parameters uncertainty or load perturbation. The simulation and experiment results show the correctness of analysis and the effectiveness of the proposed methods. The robust control strategies combined with the advanced soft switching topology improve the system performance for the practical applications. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of thermal process parameters on the mechanical properties and final microstructure of SiC-based ceramic matrix composites parts shaped by composite flow molding, and converted into ceramics by pyrolysis and reactive silicon melt infiltration. Green composite parts consisted of a thermoplastic matrix (PEEK) reinforced with continuous carbon fibers. Parts were pyrolyzed between 960°C and 2000°C and subsequently Si infiltrated between 1600°C and 1800°C, with a dwell time of 1 to 3 h. An experimental plan was defined following a design of experiment (DOE) approach. At high pyrolysis and infiltration temperatures, samples show higher modulus of rupture (280 MPa) and flexural modulus (158 GPa). A qualitative image analysis was adopted to estimate the CMC composition. A predictive model allowing the estimation of the composite toughness as a function of the significant process parameters was derived by applying the DOE methodology and the analysis of variances. The model is based on the observed correlations between the process parameters and their influence on the material property of interest. The most influential parameters are the silicon infiltration temperature and the dwell time. This is due to their control over the reaction kinetics between C and Si to obtain SiC. [ABSTRACT FROM AUTHOR]

Polymer‐derived ceramics (PDCs) have recently attracted an increasing attention because of their applications for wireless passive pressure sensors in the harsh environment. However, due to the effect of temperature on the frequency of PDC‐based wireless passive pressure sensors, it is not beneficial to accurate measurement of pressure. In this paper, a dense polymer‐derived silicon carbonitride (SiCN) ceramic was prepared by precursor infiltration and pyrolysis (PIP) technique to reduce the temperature sensitivity of PDC–SiCN‐based pressure sensor. The open porosity and density of SiCN ceramics varied from 13.34% and 1.89 g/cm3 without PIP process to 3.24% and 2.09 g/cm3 after three PIP cycles, respectively. Raman spectroscopy revealed that the level of graphitization of free carbon in dense SiCN ceramics is higher than that in porous SiCN ceramics, which would lead to an increase in the conductivity of dense SiCN ceramics. After three PIP cycles, the conductivity increased by almost two orders of magnitude from 3.01E − 10 to 1.28E − 08 S/cm. In addition, SiCN ceramic discs after PIP cycles and without PIP were applied to wireless passive pressure sensor based on resonator, which were tested at high temperature, respectively. Results confirmed that the temperature sensitivity of PDC–SiCN‐based pressure sensor decreased from 220.5 to 50.8 kHz/°C by PIP process. [ABSTRACT FROM AUTHOR]

This report presents testing of a prototype cantilevered liquid-nitrogen-cooled silicon mirror. This mirror was designed to be the first mirror for the new soft X-ray beamlines to be built as part of the Advanced Light Source Upgrade. Test activities focused on fracture, heat transfer, modal response and distortion, and indicated that the mirror functions as intended. [ABSTRACT FROM AUTHOR]

The reverse bias stability is a key concern for the commercialization and reliability of halide perovskite photovoltaics. Here, the robustness of perovskite‐silicon tandem solar cells to reverse bias electrical degradation down to −40 V is investigated. The two‐terminal tandem configuration, with the perovskite coupled to silicon, can improve the solar cell resistance to severe negative voltages when the tandem device is properly designed. While perovskite cells typically exhibit early reverse bias breakdown voltages, the serial connection with silicon cells with large shunt resistances and high voltage breakdown limits their negative polarization and prevent the passage of large current densities when reverse biased. The importance of careful optical design is illustrated, with bottom‐limited conditions required to prevent the perovskite top cell from exploring its own breakdown. This aspect is of great importance in the case of partial shading events when the solar spectrum is richer in the IR components than the standard AM1.5G. Notably, 100% of efficiency retained after polarization at −40 V in different stressing conditions is observed. The results presented suggest that standard industrial bypass diode schemes may be compatible with silicon/perovskite tandem photovoltaics and provide new guidelines for the standardization of the stressing protocols. [ABSTRACT FROM AUTHOR]

Silicon emerges as a candidate for advancing lithium ion batteries with important roles in various applications ranging from portable electronics to electric vehicles. However, despite its theoretical capacities silicon faces challenges such as unstable cycling and limited rate performance. This thorough review examines developments in improving the electrochemical performance of silicon and graphene within the context of lithium ion batteries. The focus lies on strategies for designing and synthesizing composite materials that incorporate silicon particularly when combined with graphene. Structural aspects like particle size, morphology and porosity are carefully optimized to harness the potential of silicon based anodes and graphene. The review highlights the effects resulting from these tailored design approaches, including key factors such as capacity retention, cycling stability and rate capability of the resulting anode materials. By exploring these design paradigms this review offers a comprehensive perspective on the transformative capabilities of silicon, graphene and silicon/graphene composites. It does not highlights recent advancements but also outlines future directions for innovation and practical applications. This compilation of progress contributes to the understanding of how silicon based anodes, in lithium ion batteries have evolved from small‐scale implementations to catalyzing advancements in energy utilization. [ABSTRACT FROM AUTHOR]

Silicon (Si) content in plant tissues is considered a functional trait that can provide multiple morpho‐physiological benefits to plant individuals. However, it is still unclear whether and how these individual benefits extend to plant community processes and ecosystem functioning. Here we investigated how plant Si content is associated with plant community properties and the ecosystem structure of herbaceous communities in Israel. We sampled 15 sites across the Mediterranean and desert ecosystems and built models to evaluate how plant silicon content (community‐weighted mean and standard variation) is associated with variables such as species richness, biomass production, plant cover, and functional diversity. Finally, we used model selection techniques to test whether models depicting plant Si content perform better than models using data on soil Si instead. Sites with lower susceptibility to drought had significantly more Si‐accumulating grass species and higher soils Si content. Models with plant Si content instead of soil Si, always performed better, although those considering Si content variation had overall stronger associations with community properties than only mean Si content. For instance, up to 51% of plant Si content variation was explained by climate, biomass production, and species richness, combined. Still, mean plant Si content and plant cover combined explained up to 42% of plant functional diversity. Our results suggest the that plant Si content serves as a proxy for understanding the ecological properties and functioning of arid and Mediterranean ecosystems. Nevertheless, the significance of Si has not been fully explored in other ecosystem types, where its influence may be less pronounced compared with the ecosystems examined in this study. In light of various global change scenarios, enhancing our understanding of Si as a plant functional trait could help bridge existing knowledge gaps and improve ecological modeling, thus enabling more accurate forecasts of changes in plant distributions. [ABSTRACT FROM AUTHOR]

The nanostructuring of electrodes is a common way of increasing electrocatalytic activity. Yet, the fact that the presence of insulating material in nanostructured composites can have a positive effect on efficiency was an unexpected recent finding. The rate enhancement has been linked to different electric fields at the insulator and metal interfaces, facilitating enhanced transport of reaction products into the bulk electrolyte. In this article, we further uncover the origin of the rate enhancement with parameter studies and simulations. We experimentally investigate various parameter dependencies of the alkaline Hydrogen Evolution Reaction (HER) on well‐defined nanometer‐sized Au arrays embedded in a silicon nitride insulating layer. We find a significant enhancement of the HER for all experimental conditions and opposite activity trends with pH, electrolyte concentration and the cationic species compared to a continuous Au electrode. Using a mean field model, we quantify the electrostatic interfacial pressure above the Au and the insulator patches. Combining the double layer simulations with rate equations, we demonstrate that all parameter variations can be consistently explained by the fact that the double layer structure above the insulator patches is much less rigid than above the metal islands and is independent of the applied potential. [ABSTRACT FROM AUTHOR]

With the rapid development of the photovoltaic industry, a great amount of silicon cutting waste (SCW) are being generated, which lead to a heavy environmental burden as well as a high cost of the photovoltaic industry. In this paper, the effects of Fe-containing additives and their function mechanism on recycling SCW to synthesize high-purity SiC were studied. The results show that Fe- containing additives, including Fe, Fe2O3, and Fe(NO3)3, have obvious effect on recycling SCW to synthesize SiC. And Fe(NO3)3 additive achieves the best effect. Fe(NO3)3 can effectively destroy the SiO2 film wrapped on the Si particles, so that expose the inner Si to C at lower temperatures than that of the reaction between C and SiO2. Besides, Fe(NO3)3 additive can effectively reduce the activation energy both for Si and C reactions and SiO2 and C reactions, and contribute to the transport of the raw materials as well as the dissolution and precipitation of Si and C due to the formation of the FeSi melt at low temperatures. The optimal processing conditions are determined as Fe(NO3)3 addition of 1-3 wt.% and smelting temperature of 1200-1300°C. [ABSTRACT FROM AUTHOR]

The pathway for improving lithium‐ion batteries′ energy density strongly depends on finding materials with enhanced performance. Although great efforts have been done, on the anode‐side, graphite is still the best choice. In the last decade, silicon elements are attracting growing attention as anode since their use can theoretically increase specific capacity of the negative electrode side. However, as the electrochemical mechanism involves the alligation of a large amount of Li, the silicon electrode experiences huge volume changes (more than 300 % of its initial volume), leading to fractures and pulverizations of the electrode. Herein, we propose for the first time using Molybdenum and Chromium Carbides as additive to stabilize graphite/silicon composites. Spark plasma sintering technology is used to sinter the electrode powders. We demonstrated that the presence of molybdenum or chromium carbides promotes the performance of C/Si electrodes, improving the cycling stability compared to pristine graphite/silicon electrodes. [ABSTRACT FROM AUTHOR]

A key consideration for the successful operation of hybrid energy systems will be the environmental stability of materials used for their construction, particularly when experiencing service environments containing water vapor at high temperatures. Here, we report results from the characterization of siliconized silicon carbide (Si‐SiC) prepared via binder jet additive manufacturing and reactive silicon melt infiltration after being exposed to environments representative of those in solid oxide fuel cell (SOFC) anodes, and to exhaust gases inside a microturbine operating on natural gas. In both cases, it was found that oxide scales formed on the surface and that these scales were dense, continuous, and well‐bonded to the substrates, although there was evidence of transverse and longitudinal cracking most likely as a result of mismatches in the thermal expansion of the scale and the substrate. Measured values of the thickness of the oxide scale were compared to those predicted by parabolic oxidation kinetics of silicon, but the potential effects of silica volatilization induced by water vapor, and silica reduction when exposed to hydrogen are discussed. The overall results showed that the oxide scale is expected to be protective under the conditions of hybrid power generation systems. [ABSTRACT FROM AUTHOR]

Silicon powder kerf loss from diamond wire sawing in the photovoltaic wafering industry is a highly appealing source material for use in lithium‐ion battery negative electrodes. Here, it is demonstrated for the first time that the kerf particles from three independent sources contain ~50 % amorphous silicon. The crystalline phase is in the shape of nano‐scale crystalline inclusions in an amorphous matrix. From literature on wafering technology looking at wafer quality, the origin and mechanisms responsible for the amorphous content in the kerf loss powder are explained. In order to better understand for which applications the material could be a valuable raw material, the amorphicity and other relevant features are thoroughly investigated by a large amount of experimental methods. Furthermore, the kerf powder was crystallized and compared to the partly amorphous sample by operando X‐ray powder diffraction experiments during battery cycling, demonstrating that the powders are relevant for further investigation and development for battery applications. [ABSTRACT FROM AUTHOR]

Two‐dimensional dopant layers (δ‐layers) in semiconductors provide the high‐mobility electron liquids (2DELs) needed for nanoscale quantum‐electronic devices. Key parameters such as carrier densities, effective masses, and confinement thicknesses for 2DELs have traditionally been extracted from quantum magnetotransport. In principle, the parameters are immediately readable from the one‐electron spectral function that can be measured by angle‐resolved photoemission spectroscopy (ARPES). Here, buried 2DEL δ‐layers in silicon are measured with soft X‐ray (SX) ARPES to obtain detailed information about their filled conduction bands and extract device‐relevant properties. This study takes advantage of the larger probing depth and photon energy range of SX‐ARPES relative to vacuum ultraviolet (VUV) ARPES to accurately measure the δ‐layer electronic confinement. The measurements are made on ambient‐exposed samples and yield extremely thin (< 1 nm) and dense (≈1014 cm−2) 2DELs. Critically, this method is used to show that δ‐layers of arsenic exhibit better electronic confinement than δ‐layers of phosphorus fabricated under identical conditions. [ABSTRACT FROM AUTHOR]

Summary: Some plant species tolerate and accumulate high levels of metals or metalloids in their tissues. The elemental defence hypothesis posits that metal(loid) hyperaccumulation by these plants can serve as protection against antagonists. Numerous studies support this hypothesis. In addition, as other plant species, hyperaccumulators synthesise specialised metabolites that can act as organic defences. In principle, the composition and concentration of plant‐specialised metabolites vary pronouncedly not only among species, but also within species and within individuals. This variation is called chemodiversity. Surprisingly, the role of chemodiversity has received little attention in elemental defence. Thus, we advocate that the concept of the elemental defence hypothesis should be extended and linked to the multifunctionality of plant chemodiversity to better understand the eco‐evolutionary dynamics and maintenance of metal(loid) hyperaccumulation. Comprehensive literature studies revealed that both metal(loid)s and specialised metabolites acting as defences are highly diverse in some hyperaccumulators and the biosynthetic pathways of these two types of defences are partly intertwined. Several edaphic‐, population‐, temporal‐ and spatial‐related factors were found to influence metal(loid) diversity, which should be considered in the elemental defence hypothesis. We thus present a novel synthesis and outlook to extend the elemental defence hypothesis in the light of chemodiversity. [ABSTRACT FROM AUTHOR]

Many temperate grasses are both hyper‐accumulators of silicon (Si) and hosts of Epichloë fungal endophytes, functional traits which may alleviate environmental stresses such as herbivore attack. Si accumulation and endophyte infection may operate synergistically, but this has not been tested in a field setting, nor in the context of changing environmental conditions. Predicted increases in atmospheric CO2 concentrations can affect both Si accumulation and endophyte function, but these have not been studied in combination.We investigated how elevated atmospheric CO2 (eCO2), Si supplementation, endophyte‐presence and insect herbivory impacted plant growth, stoichiometry (C, N, P and Si), leaf gas exchange (rates of photosynthesis, stomatal conductance, transpiration rates) and endophyte production of anti‐herbivore defences (alkaloids) of an important pasture grass (tall fescue; Lolium arundinaceum) in the field.eCO2 and Si supplementation increased shoot biomass (+52% and +31%, respectively), whereas herbivory reduced shoot biomass by at least 35% and induced Si accumulation by 24%. Shoot Si concentrations, in contrast, decreased by 17%–21% under eCO2. Si supplementation and herbivory reduced shoot C concentrations. eCO2 reduced shoot N concentrations which led to increased shoot C:N ratios. Overall, shoot P concentrations were 26% lower in endophytic plants compared to non‐endophytic plants, potentially due to decreased mass flow (i.e. observed reductions in stomatal conductance and transpiration). Alkaloid production was not discernibly affected by any experimental treatment. The negative impacts of endophytes on P uptake were particularly strong under eCO2.We show that eCO2 and insect herbivory reduce and promote Si accumulation, respectively, incorporating some field conditions for the first time. This indicates that these drivers operate in a more realistic ecological context than previously demonstrated. Reduced uptake of P in endophytic plants may adversely affect plant productivity in the future, particularly if increased demand for P due to improved plant growth under eCO2 cannot be met. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

The combination of graphene and silicon in hybrid electronic devices has attracted increasing attention over the last decade. Here, a unique technology of graphene‐on‐silicon heterostructures as solution‐gated transistors for bioelectronics applications is presented. The proposed graphene‐on‐silicon field‐effect transistors (GoSFETs) are fabricated by exploiting various conformations of channel doping and dimensions. The fabricated devices demonstrate hybrid behavior with features specific to both graphene and silicon, which are rationalized via a comprehensive physics‐based compact model which is purposely implemented and validated against measured data. The developed theory corroborates that the device hybrid behavior can be explained in terms of two independent silicon and graphene carrier transport channels, which are, however, strongly electrostatically coupled. Although GoSFET transconductance and carrier mobility are found to be lower than in conventional silicon or graphene field‐effect transistors, it is observed that the combination of both materials within the hybrid channel contributes uniquely to the electrical response. Specifically, it is found that the graphene sheet acts as a shield for the silicon channel, giving rise to a nonuniform potential distribution along it, which impacts the transport, especially at the subthreshold region, due to non‐negligible diffusion current. [ABSTRACT FROM AUTHOR]

Si2N2O, which shows high radiative cooling ability, was mixed and hardened with ordinary Portland cement to prepare cement specimens having radiative cooling abilities. The bulk cement specimens were prepared with diameters of 50 mm and two different thicknesses of 3 and 10 mm, and Si2N2O powder were mixed with 2 and 10 wt%. The temperatures of the blank specimen (without radiative cooling Si2N2O powder) and the cement composite specimens were measured in a thermostatic chamber maintained at ambient temperature, and the radiative cooling abilities of the specimens were evaluated. The obtained specimens showed a radiative cooling ability in the range 0.077–0.92 W/m2; thus, the results of this study suggested the possibility of a cement composite with passive cooling property. [ABSTRACT FROM AUTHOR]

Silica‐aluminium composite powders are important precursors for the preparation of sealant coatings by supersonic flame spraying. Micron‐scale silica‐aluminium composite powders can be prepared using a planetary ball mill, but powder agglomeration often leads to composite failure. Using relevant modelling software to build the 3D modelling of the ball mill jar, which based on the discrete element method, using the Hertz–Mindlin contact model and after specifying the simulation boundary conditions, the ball mill process was simulated and analysed. Visualise the influence of important process parameters such as frequency, size and diameter of milling balls and ball‐to‐powder weight ratio, and systematically analyse the microscopic morphology and composite condition of the agglomerated and dispersed powders. The results show that the ball motion during the ball milling process is mainly divided into three representative types: ball–ball impact, ball crushing motion against the jar wall and ball–wall impact. The energy transfer efficiency of the milling balls to the powder system is highest when the ratio of the three types of motion is uniform. SEM images and EDS spectra showed that the aluminium powder was sufficiently crushed, with an average particle size below 1 μm. The aluminium powder was uniformly distributed on the surface of the silicon powder, and the particle size of the composite silicon aggregates was sufficiently reduced. [ABSTRACT FROM AUTHOR]

The volume change of the silicon anode seriously affects the electrode integrity and cycle stability. Herein, a binder, GCA13, with energy dissipation function and surface stability effect is proposed to enhance the cycle life and specific capacity. Unlike traditional binders that protect silicon electrodes through long‐chain networks, GCA13 introduces citric acid molecules with short‐range functions on the long‐chain guar gum through weak interconnection. This short‐range action is similar to the function of a spring, which can effectively buffer the silicon particle pulverization caused by the volume change. Therefore, the electrode can effectively maintain structural integration with ignorable cracks and alleviated thickness swelling. Thus, the Si@GCA13 anode exhibits a high reversible capacity of 1184 mAh g−1 under 2 A g−1 after 740 cycles with a latter coulombic efficiency of 99.9%. Extraordinarily, benefiting from the superior properties of the GCA13 binder, the electrode shows remarkable cycling stability under low (−15 and 0 °C) and high temperatures (60 °C). The work demonstrates the great potential of this binder design strategy to achieve the overall property promotion of Si anodes for practical application even under harsh service conditions. [ABSTRACT FROM AUTHOR]

Metal‐semiconductor heterostructures providing geometrically reproducible and abrupt Schottky nanojunctions are highly anticipated for the realization of emerging electronic technologies. This specifically holds for reconfigurable field‐effect transistors, capable of dynamically altering the operation mode between n‐ or p‐type even during run‐time. Targeting the enhancement of fabrication reproducibility and electrical balancing between operation modes, here a nanoscale Al‐Si‐Al nanowire heterostructure with single elementary, monocrystalline Al leads and sharp Schottky junctions is implemented. Utilizing a three top‐gate architecture, reconfiguration on transistor level is enabled. Having devised symmetric on‐currents as well as threshold voltages for n‐ and p‐type operation as a necessary requirement to exploit complementary reconfigurable circuits, selected implementations of logic gates such as inverters and combinational wired‐AND gates are reported. In this respect, exploiting the advantages of the proposed multi‐gate transistor architecture and offering additional logical inputs, the device functionality can be expanded by transforming a single transistor into a logic gate. Importantly, the demonstrated Al‐Si material system and thereof shown logic gates show high compatibility with state‐of‐the‐art complementary metal‐oxide semiconductor technology. Additionally, exploiting reconfiguration at the device level, this platform may pave the way for future adaptive computing systems with low‐power consumption and reduced footprint, enabling novel circuit paradigms. [ABSTRACT FROM AUTHOR]

Background: To investigate the intrinsic mechanism that causes the darkening of liquid foundations. Materials and method: A total of 36 commercial liquid foundations were firstly studied for preliminary screening of influencing factors. A basic liquid foundation was developed for controlling variables to study the influence of each single factor. These samples were evenly spread on the standard opacity charts with the thickness of 100 μm and applied onto human inner forearm skin with the dosage of 2 mg/cm2. The discoloration of each sample was continuously recorded using spectrophotometers and reported in the CIE 1976 L*a*b* color space for at least 120 min, and ΔE was calculated to describe the severity of darkening. Results: One hundred twenty‐minute ΔE of all commercial foundations was highly negatively correlated with their 120‐min ΔITA° (R2 = 0.88, p < 0.01). A strong positive correlation was found between the severity of darkening and the volatilization of the basic foundations (R2 = 0.83, p < 0.01). And the darkening of silicone‐based basic foundations using pigment coating with silicon is weaker than those without silicon (p < 0.05). Conclusion: The process of the discoloration of liquid foundation is accompanied by the decrease of ITA° and manifested as darkening. The volatilization rate of the product and the coating method of the pigments used in the formula can noticeably affect the darkening of the liquid foundation. [ABSTRACT FROM AUTHOR]

The melt of silicon, hindering nitridation for its agglomeration, should be avoided in the direct nitridation of silicon to synthesize silicon nitride powders, although liquid phase facilitates nitridation. Therefore, we proposed a method to nitride molten silicon without agglomeration. Thermogravimetric and in situ Raman studies on the nitridation process of molten silicon were performed. The as‐prepared silicon nitride samples were found to be micron clusters composed of submicron grains with high α‐Si3N4 content. The nitridation of molten silicon at 1500°C was completed after 500 s and 109 times faster than the nitridation of solid silicon at 1350°C. β‐Si3N4 is produced dominantly by α–β‐phase transition. Less nitridation time and low temperature can decrease the β‐Si3N4 content. The rapid nitridation was owning to core–shell structure Si@Si3N4, which was formed after the initial nitridation of silicon particles and hindered the agglomeration of molten silicon. [ABSTRACT FROM AUTHOR]

An HfO2‐doped Si bond layer is expected to work at higher temperature with better oxidation resistance of environmental barrier coatings for SiC‐based ceramic matrix composites. Establishing the relationship between process parameters and powder feeders with the property of coatings could help to further optimizing their performance. Three sets of plasma spray processes and two kinds of HfO2 powders were used to fabricate Si–HfO2 bond coats with a different Si/HfO2 ratio. The particle size of HfO2 greatly affects the composition of coat, where smaller one induced an uncontrollable Si/HfO2 ratio inside coatings. Larger HfO2 powder greatly improved the composition uniformity with an Si/HfO2 ratio similar to the starting feeder. However, phase segregation occurred for both cases, indicating the limit of mechanical mixing method to make composite feedstock. More strategies should be explored for precise control of the phase and composition of composite coatings from spray technique. [ABSTRACT FROM AUTHOR]

All‐optical likelihood calculation has the potential to improve the performance of operating speed and power consumption in future communication systems. The author previously proposed a novel scheme of likelihood calculation, which is capable of applying multi‐value modulation. However, these studies have a limitation that requires higher integration into an actual system. In this study, an optical device of likelihood calculation for a 4‐bit quadrature phase‐shift keying (QPSK) modulated signal (i.e. two sequential QPSK symbols) is demonstrated. The integrated device consists of two delayed interferometers with silicon waveguide. The device is designed according to the types of 4‐bit code string as follows (00 00), (00 11), (11 00), and (11 11), and the output light waveform from the device is observed by an oscilloscope for a plurality of 4‐bit QPSK signals. The light intensity obtained from the device accurately corresponds to the Hamming distance between the code string and the input signal. The results indicate that the proposed scheme correctly calculates a likelihood for a 4‐bit QPSK signal at 10 Gbaud. [ABSTRACT FROM AUTHOR]

A simple and accurate analytical model for the estimation of switching losses on power MOSFETs is proposed. It consists of simplifying the non‐linear behaviour of Miller capacitance as a function of voltage. Experimental results are used to validate the model in the 5–500 kHz range. The proposed analytical model is compared to other frequently used methods. Results confirm the accuracy of the proposed model in different voltage levels, using four different MOSFET part numbers, spanning three technologies: SiC, superjunction, and conventional silicon. Because of its simplicity of implementation, it is especially recommended for applications that design converters by evaluating a large database of transistor part numbers. [ABSTRACT FROM AUTHOR]

Silicon anodes are vital for the next generation ultra‐high capacity rechargeable lithium‐ion batteries. This study investigates ultrasmall silicon nanopowder (30–40 nm) as an anode material. Its high capacity > 3700 mAh/g makes it attractive, given the current theoretical capacity of graphite is ten times lower (370 mAh/g). However, it has severe instability due to volume expansion of silicon particles during charging. Hence, BaTiO3 nanomaterial was used to stabilise the cycling ability and improve the capacity. This study showed that silicon anode with BaTiO3 retained 40% of its original capacity after the 100th cycle where the silicon anode without BaTiO3 lost almost all of its capacity. The silicon anode with BaTiO3 also managed to regain and sustain ∼800 mAh/g of its capacity at slow charging rate compared to the silicon anode without BaTiO3. Water was used as a solvent and the basic changes in oxidation states of the silicon anode were investigated using X‐ray photoemission spectroscopy and proved the creation of COx at different rates of repeated cycling. The work also provides detailed mapping of the different stages as the silicon nanopowder undergoes cycling. It provides a simple and effective way of synthesising and testing nearly pure silicon anodes. [ABSTRACT FROM AUTHOR]

Silicon (Si) uptake and deposition (silicification) in tissues is known to alleviate stresses and generally improve plant health. This is mostly studied in Si-high accumulators, such as grasses, with comparatively less known about its effects on other plant functional groups, such as legumes. There is speculation that Si may positively impact the symbiosis between legumes and the nitrogen-fixing bacteria (rhizobia) they associate with, but this is poorly understood. This study examined the effects of Si enrichment on legume species associated with rhizobia and the potential underlying mechanism of Si impacts. 2. We conducted a glasshouse experiment with lucerne Medicago sativa and barrel medic M. truncatula associated with a model rhizobial strain. Six genotypes (three per species) were either supplemented with Si (+Si) or untreated (-Si). We quantified 16 functional traits which could be classified as plant growth, physiology, elemental chemistry, nodule activity and nitrogen fixation. 3. The two legume species responded to Si distinctively. For example, Si supplementation increased shoot biomass by more than 10% in lucerne but growth was unaffected in barrel medic. Conversely, nitrogen-fixing enzyme (nitrogenase) activity was promoted by more than 85% in +Si barrel medic plants but not in lucerne. Moreover, Si supplementation of lucerne increased the concentrations of Si in leaves by more than 36% but not in root nodules. Increased foliar concentrations of Si in lucerne were positively associated with increased shoot and root biomass in Sequel and Trifecta genotypes, respectively. Conversely, Si supplementation of barrel medic increased the concentration of Si in root nodules by 29% but not that in foliar tissues. Nitrogenase activity and where silicification occurred, differed between genotypes in barrel medic; nitrogenase activity was correlated with concentrations of Si in root nodules rather than that in foliar tissues in one genotype (Sephi) but the reverse was true in another (Hannaford). 4. This study demonstrates that two closely related legume species can respond to Si in distinct ways, depending on plant genotype and symbiosis. These results present the overlooked function of Si in legume-rhizobia interactions, which could potentially enhance productivity of this important group of plants. [ABSTRACT FROM AUTHOR]

The authors report experimental investigations on Hall sensors based on AlGaN/GaN heterojunctions grown on silicon 111 (Si 111) substrates. Realisation of two‐dimensional electron gas‐based Hall sensors on Si substrates can have the advantages of low cost and integrability with complementary metal‐oxide semiconductor circuits. Design and fabrication of such Hall sensors and their characterisation over a wide temperature range of 75 to 500 K are reported. The authors experimentally investigate the temperature dependence of the transresistances, sheet resistance and current‐related sensitivity (or gain) of such Hall sensors. The current‐related sensitivity is shown to be reasonably constant over the complete temperature range and certain inevitable variations in current‐related sensitivity can easily be compensated. The temperature dependence of the transresistance can be used for such compensation. The variation of the geometrical correction factor of the Hall sensor with the applied magnetic field strength and the operating temperature is also studied. The authors also demonstrate the possibility of realising Hall sensors with a high geometrical correction factor (≈0.97), which is practically insensitive to variations in temperature (≃2% from 75 to 500 K) and applied magnetic field, for applications such as in electromechanical devices. [ABSTRACT FROM AUTHOR]