Nickel oxide (NiO) is a versatile material with immense potential for next-generation optoelectronic and energy devices due to its stability, wide band gap, and tunable properties. NiO thin films were deposited under different Ar/O2 atmospheres using RF magnetron sputtering to investigate the influence of oxygen incorporation on their structural, morphological, and optical properties. XRD analysis revealed that the crystallite size decreases from 12 nm for NiO-A85 to 4 nm for oxygen-assisted films, accompanied by an increase in lattice strain and dislocation density. FESEM and AFM studies showed a transition from smooth and compact morphology (Rq ≈6.7 nm) to rougher surfaces with increased grain size and surface roughness (Rq ≈16.0 nm) for oxygen-rich films. Optical measurements indicated high transparency in the visible region (70–100
B4C–TiB2–SiC–graphite composites with high relative densities were fabricated by reactive hot pressing at 2000 °C using B4C–TiC–SiC powder mixtures with various compositions. TiB2 and graphite were in-situ synthesized during the reactive hot pressing of B4C–TiC–SiC powder mixtures. Lamellar graphite phases were synthesized at the B4C grain boundaries and B4C/TiB2 interface. The grain size of B4C gradually decreased with increasing TiB2/graphite and SiC contents. With the increases in the TiB2/graphite and SiC contents in the B4C composites, the flexural strength was increased from 484.8 ± 14 to 597 ± 9 MPa, while the fracture toughness was increased from 4.77 ± 0.24 to 6.82 ± 0.51 MPa·m1/2. The Vickers hardness was preserved to some extent above 30 GPa regardless of the amounts of reinforced TiB2, SiC, and graphite in the B4C composites.
Plastic waste accumulation poses mounting environmental threats globally. Upcycling these materials into valuable nanomaterials, like graphene nanosheets (GNs), provides a promising sustainability solution. This study synthesized GNs from plastic waste and evaluated their efficacy as drilling fluid additives. Various analytical techniques characterized the produced GNs. Experiments examined the impact of 0.05–0.44 wt
Animal-derived foods are major contributors to dietary exposure to per- and polyfluoroalkyl substances (PFAS). To support exposure assessment in the Total Diet Study (TDS), a simultaneous liquid chromatography-tandem mass spectrometry (LC–MS/MS) method for twelve PFAS in protein-rich foods was validated using boiled chicken breast as a representative matrix. The method showed high linearity (R2 > 0.997), with limits of quantification below 0.1 µg/kg for eleven PFAS and 0.121 µg/kg for PFNA. Recoveries ranged from 81.1 to 110
Anthropogenic carbon dioxide (CO2) emissions drive global climate change, motivating the development of bioprocesses that improve carbon utilization and enable CO2 recycling. In this study, we developed a CO2-fixing Saccharomyces cerevisiae chassis for single-cell protein (SCP) production using xylose derived from cellulosic biomass as a carbon source. A RuBisCO- based CO2-fixation pathway was previously integrated into a xylose-utilizing strain, enabling the routing of CO2 into central metabolism. Flux balance analysis combined with 13C-based intracellular metabolite analysis verified the assimilation of externally supplied CO2 into central metabolism, suggesting the potential for assimilation of fermentation-derived CO₂ and improved carbon utilization during SCP production. To enhance SCP production, the PAN2 gene encoding a component of the poly(A)-ribonuclease complex, previously associated with increased global protein production in S. cerevisiae, was truncated in the CO2-fixing strain. Under anaerobic conditions, the engineered strain exhibited a significant increase in cellular protein content, accompanied by an overall upward trend in amino acid levels relative to the parental strain. Collectively, these results metabolically verify RuBisCO-mediated CO2-fixation in yeast strain and demonstrate the feasibility of coupling CO2-fixation to SCP production. This work also provides insights into the potential of integrating CO₂-fixation with renewable carbon metabolism and establishing a proof-of-concept platform for the development of low-carbon yeast bioprocess.
