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Coal gangue (CG), a silicon-rich solid waste, contains silicon in a crystalline form unavailable to plants. This study developed an energy-efficient (NH4)2SO4-NaOH co-activation process to convert CG into an efficient silicon fertilizer. Thermodynamic analysis confirmed the feasibility of (NH4)2SO4 as an activator above 400°C. Optimal activation was achieved at a (NH4)2SO4/CG mass ratio of 0.2, 450°C for 30 min (AS), yielding citric acid-leachable Si and Al concentrations of 429.15 and 729.44 mg/L, respectively. The addition of 5% NaOH further enhanced Si leaching to 446.50 mg/L by promoting siloxane network depolymerization. Characterization (XRD, XPS, FTIR) confirmed the transformation of silicon to more bioavailable forms. The co-activated sample (AS-CS) exhibited a superior biphasic release pattern with high initial release and sustained cumulative release (494.53 mg/L). While (NH4)2SO4 activation increased leachable ammonia nitrogen and sulfate, NaOH addition effectively reduced the NH3-N (sum of the nitrogen content in both free ammonia and ammonium ions in aqueous solution). levels via volatilization. Soil incubation revealed that AS-CS moderated the shifts in microbial community structure induced by (NH4)2SO4 alone. This work provides a sustainable strategy for CG valorization into silicon fertilizer, balancing activation performance with environmental safety, supporting circular economy goals.

Oxidized mesoporous silicon, composed of a silicon skeletal core surrounded by a silicon oxide shell, reacts with aqueous calcium ions to generate a modified shell comprised of a mixed silicon oxide-calcium silicate phase. The performance of the metal silicate phase as a condenser for the xanthene dye calcein and as a modulator for the dissolution of the porous silicon host and the release of calcein into aqueous media is studied using a chip-based format. The reaction conditions for oxide shell formation (thermal, ozone, or hydrogen peroxide oxidation) and for its conversion to calcium silicate (reaction time and pH) are compared. The optimal conditions are determined, and dissolution of the composite material is studied as a function of pH and buffer composition. The composite shell is stable under neutral aqueous conditions, but it dissolves 30 times faster at pH 4. In phosphate-buffered saline (PBS), incorporation of phosphorus into the shell is observed, which suppresses the rate of dissolution through secondary mineralization. Loading experiments using a nanoparticle formulation of the material show efficient encapsulation of calcein (21% by mass). The dye is released more rapidly at pH 4 than at pH 7, and the presence of phosphate in the pH 7 buffer further slows release.

Silicon-based anodes are considered promising alternatives to graphite anodes owing to their high theoretical lithium-storage capacity and abundant reserves. However, silicon nanoparticle anodes are severely limited by large volume expansion, unstable interfacial chemistry, and poor electrical connectivity during repeated lithiation/delithiation. Herein, we develop a yolk-shell N-doped carbon network (NCN) strategy to construct Si@void@NCN composites. The optimized Si@void@NCN-1 achieves a balanced architecture between void buffering and carbon network integrity, delivering a high initial discharge capacity of 1245.5 mAh g-1 and an initial charge capacity of 735.8 mAh g-1. It also demonstrates stable long-term cycling performance, retaining a reversible capacity of 402.5 mAh g-1 after 500 cycles at 0.5 A g-1 with a capacity retention of 68.66%, and shows improved rate reversibility and electrode structural stability, with an electrode thickness increase of only 80.4% after rate cycling, much lower than that of densely carbon-coated Si@C. Kinetic analysis, post-cycling structural characterization, and in situ EIS further reveal that the yolk-shell void-buffering structure and the N-doped three-dimensional conductive network act synergistically to mitigate Si volume expansion, enhance structural stability, and facilitate electron/ion transport. This study emphasizes the importance of integrating buffering structures with Si/C composites, providing guidance for the rational design of advanced silicon-based electrode materials.

Perfluorooctanoic acid (PFOA), a persistent and bioaccumulative contaminant of emerging concern, poses substantial ecological risks to marine primary producers and can disrupt critical biogeochemical cycles. Marine diatoms are pivotal in coupling carbon (C) and silicon (Si) cycling and contribute substantially to oceanic C sequestration via the biological C pump. However, the mechanisms underlying PFOA-induced effects on diatom physiology and associated biogeochemical processes remain poorly understood. This study investigated the impacts of environmentally relevant (5 ng·L-1) and elevated (500 ng·L-1) PFOA concentrations on the model marine diatom Phaeodactylum tricornutum. PFOA exposure significantly altered dissolved silicon (DSi) dynamics, with DSi concentrations increasing by 5.95% and 21.96% at 5 and 500 ng·L-1, respectively. Biogenic silica (BSi) content increased by 9.66% at low PFOA but decreased by 1.01% at high PFOA. Dissolved organic carbon (DOC) decreased by 2.15% and 8.02%, while dissolved inorganic carbon (DIC) increased by 11.30% and 32.45% under low and high PFOA treatments, respectively. Transcriptomic analysis indicated that 500 ng·L-1 PFOA downregulated genes associated with C fixation while upregulating genes involved in the tricarboxylic acid (TCA) cycle. Additionally, expression of PHATRDRAFT_48708 was suppressed, whereas Si transporter 4 (SIT4) was upregulated, indicating dysregulation of Si homeostasis. These findings demonstrate that PFOA disrupts C-Si coupling at the cellular level in P. tricornutum, highlighting a potential mechanism by which PFOA may disrupt diatom-mediated C sequestration. Future validation using ecologically representative, heavily silicified diatom taxa is required to extrapolate these effects to natural oceanic C fluxes.

The conformal coating of perovskites on textured silicon for tandem solar cells requires scalable deposition methods, for which hybrid vacuum-solution processing, using an evaporated inorganic scaffold (Pb/Cs halides) followed by solution conversion, is promising. Yet multisource coevaporation of the scaffold, as commonly used for lab-scale devices, is complex and costly to implement at an industrial scale. Here, we investigate sequential single-source evaporation of the inorganic scaffold as an industrially viable alternative. Five sequentially evaporated scaffold stacks were compared to a coevaporated reference. Despite differences in PbI2 conversion, halide distribution, and morphology, all showed similar single-junction device power conversion efficiencies (∼19%). The best scaffold (a PbI2/CsBr/PbI2/CsBr/PbI2 stack) achieved 28.4% in perovskite/silicon tandems without molecular additives, matching the coevaporated reference (28.3%). This work demonstrates that sequential deposition of the inorganic scaffold offers a scalable route to high-efficiency tandems.

With the miniaturization of electronic devices, the demand for high-efficiency thermal management materials has become increasingly urgent. Although traditional high-filler random blending composites can enhance thermal conductivity, they often do so at the expense of mechanical properties and lightweight advantages. Therefore, constructing oriented thermal conduction networks at low filler loadings has become a core challenge in current research. This study proposes an interface engineering strategy based on a tannic acid (TA) molecular bridging layer to modify silicon carbide (SiC). By leveraging the self-polymerization and strong adhesion properties of TA, a dense fish scale SiC coating was formed on the surface of highly oriented woven cellulose acetate (WF) through a simple impregnation process. After compositing with a polyurethane (PU) matrix, the obtained WF/TA/SiC/PU exhibits anisotropic thermal conductivity. It has an axial thermal conductivity of 0.44 W/mK, an increase of 411% over PU, and the decomposition temperature has increased by 18.2 °C. Additionally, the composite axial thermal response rate significantly outperforms both the radial direction and PU. This research demonstrates a new approach for achieving high-efficiency thermal management at low filler loadings, providing a scalable pathway for the development of sustainable, lightweight, and high-performance anisotropic heat dissipation devices.

Silicon (Si) has been recognized as a beneficial element in plant disease resistance; however, its role under field conditions in barley remains insufficiently explored. This study evaluated the effects of soil-applied Si and its interaction with cultivars and fungicide programs on foliar disease control and yield components in barley over four growing seasons. Two field experiments were conducted: Study I assessed the interaction between Si supply, cultivars, and fungicide application, while Study II evaluated different fungicide programs under Si supply. Silicon application consistently reduced disease severity and the area under the disease progress curve for powdery mildew and leaf spots across cultivars and seasons. The combined use of Si and fungicides resulted in the greatest disease reduction. Cultivar BRS Cauê, showing higher partial resistance than BRS Brau, showed greater responsiveness to Si, which was associated with higher foliar Si concentration. Fungicide programs P2 [sprays at growth stage (GS) 12, GS26, GS37, and GS61] and P3 (sprays at GS12, GS31, and GS 61) were the most effective for disease control and under Si supply. Fungicide program P3, despite one fewer application, achieved disease control comparable to P2, suggesting the potential for optimizing fungicide use under Si supply. Grain yield increases closely followed reductions in disease intensity, with the highest yields observed under combined Si supply and optimized fungicide programs. These findings demonstrate that Si contributes to disease reduction and yield improvement and may serve as a key component of integrated and sustainable disease management in barley.

Silicon (Si) is an essential trace element involved in multiple physiological processes of animals. This study aimed to investigate the dose-dependent effects of dietary silica (SiO2) supplementation on production performance and key blood parameters in laying hens. A total of 360 hens were randomly assigned to five groups (6 replicates/group, 12 hens/replicate) and fed basal diets supplemented with 0% (control), 0.1%, 0.2%, 0.4%, or 0.8% SiO2 for 8 weeks. Laying performance, egg quality, serum immune indices, reproductive hormone levels, antioxidant status, and serum trace element concentrations were determined. The results showed that dietary SiO2 supplementation significantly affected egg production rate (p < 0.05), with the 0.2% group achieving the highest rate compared to the control. For egg quality, yolk weight and yolk thickness were significantly reduced only in the 0.8% group (p < 0.05), while other parameters were unaffected (p > 0.05). Dietary supplementation with 0.2%, 0.4%, and 0.8% silica significantly increased serum levels of IL-2 and IL-4 (p < 0.05), whereas the 0.8% supplementation decreased IL-1 levels (p < 0.05). Compared with the control group, serum IgA and IgG levels were elevated in the 0.2%, 0.4%, 0.8% silica-supplemented groups (p < 0.05), and serum IgM levels were higher in the 0.4% and 0.8% groups (p < 0.05). Regarding reproductive hormones, dietary SiO2 significantly increased serum concentrations of &#x3b2;-endorphin, estradiol, growth hormone, luteinizing hormone, and progesterone (p < 0.05), with follicle-stimulating hormone elevated in the 0.4% and 0.8% groups (p < 0.05). Dietary silica supplementation did not affect serum activities of SOD, GSH-Px, CAT, or T-AOC. Serum POD activity decreased gradually and was significantly lower in the 0.2%, 0.4%, and 0.8% groups than in the control group (p < 0.05). Furthermore, SiO2 supplementation significantly altered serum Cu and Zn levels (p < 0.05), with the 0.8% group having the highest Ca concentration and the 0.1-0.8% groups showing increased Zn levels compared to the control; no effects on Fe and Mn were observed (p > 0.05). In conclusion, dietary supplementation with 0.2-0.4% SiO2 effectively improves egg production rate, along with enhancing immune function, modulating reproductive hormone secretion, and regulating serum Cu/Zn homeostasis in late-phase laying hens.

This manuscript introduces a novel biosystem consisting of filamentous fungi and luminescent silicon nanoparticles (Si-NPs). The microorganisms were cultivated in a nutrient solution containing Si-NPs, acquiring a dense layer of abiotic material. The biohybrid entities were characterized using a combination of microscopy and spectroscopy techniques. Intriguingly, in addition to incorporating Si-NPs into the fungal cell wall, we observed the internalization of these nanoparticles within fungal organelles. Moreover, the apparent crystallite size of the Si-NPs within the fungal biohybrids was notably smaller than that of the synthesized Si-NPs, indicating that, under the cultivation and preparation conditions, microorganisms assimilate smaller Si-NPs more readily than larger ones. Consequently, nanoparticles smaller than 10 nm may permeate the cell wall and be concentrated in vacuoles, as observed by fluorescence microscopy.

Most quantum key distribution (QKD) silicon photonic chips rely on carrier depletion modulators (CDM), which typically require driving voltages beyond 5 V due to their limited modulation efficiency. In this work, we employ a carrier injection modulator (CIM) for quantum bit encoding, which offers a fundamentally higher modulation efficiency and thus a path to significantly lower operating voltages. Through structural optimization, the CIM achieves a half-wave voltage of 1.1 V (DC) and 1.28 V (at 100 MHz), with a modulation depth exceeding 24 dB under both conditions. Successful demonstrations of intensity state preparation as well as polarization state modulation were also conducted. These results confirm the suitability of the CIM for compact and energy-efficient QKD transmitters operating at CMOS-compatible voltages.

This paper presents the results of the preparation and electrical characterization of Ru-Si-O thin-film nanocomposites deposited by magnetron sputtering (pDC) with varying oxygen content ranging from 0% to 50%. Measurements were conducted over a wide frequency range of 50 Hz-5 MHz and temperatures of 20-373 K. Conductivity analysis revealed that DC conduction occurs at low frequencies (&#x2264;103 Hz), while an increase in conductivity associated with electron tunneling mechanisms is observed at higher frequencies. The determined charge transport activation energies range from 3 &#xd7; 10-4 eV for the oxygen-free sample to 6 &#xd7; 10-2 eV for the high-oxygen samples, indicating a significant effect of composition on the conduction mechanisms. In samples containing 30% and 50% oxygen, two characteristic frequency ranges for the activation of transport processes were observed (e.g., ~102-103 Hz and 104-106 Hz), suggesting the coexistence of multiple tunneling mechanisms. Phase angle analysis revealed a transition from values near -90&#xb0; at 151 K to values near 0&#xb0; at 333 K, characteristic of parallel RC systems. The minimum dielectric loss tangent occurs in the range of 103-105 Hz, corresponding to Maxwell-Wagner relaxation. The dispersion coefficient &#x3b1; reaches maximums in two frequency ranges, decreasing with increasing oxygen content. EDS analysis showed a decrease in Ru content from ~24.9 at.% (0% O2) to ~0.7 at.% (50% O2) and an increase in oxygen content to ~78 at.% at 10% O2. The results confirm the transition from metallic conduction to tunneling and hopping mechanisms with increasing oxidation state of the structure.

A method for synthesizing theranostic nanoparticles (NPs) based on a silica core, a mercapto spacer, a cardioprotector, and a fluorescent dye has been developed. The total amount of grafted mercapto groups was 0.079 mmol/g. The amount of accessible mercapto groups on the surface of the synthesized particles, calculated using the Kunkel, Buckley, and Gorin method, was 0.025 mmol/g. A total of 0.031 mmol/g of adenosine and 0.0087 mmol/g of indocyanine green are grafted onto the mercapto spacer. Both substances are presumably attached via hydrogen bonding to the modified silica nanoparticle in a ratio of 60/40% for adenosine and indocyanine green, respectively. The resulting nanoparticles exhibit no hemolytic activity. Intensive adenosine release occurs within 90 min and continues for up to 24 h. Based on biodistribution, significant accumulation of the nanoparticles occurs in the liver.