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Epoxy resin (EP) is one of the most widely-used insulating support materials in electrical power systems, with its insulating performance playing an important role in high-voltage engineering. In this study, a nanosecond pulse-driven Ar/Octamethylcyclotetrasiloxane (OMCTS) plasma jet is developed for fabricating nanocomposite dielectric materials to enhance their EP properties. It is demonstrated that the plasma-enabled polymerization effectively modifies the physical morphology and chemical composition of EP surfaces, where the surface roughness greatly increases with the deposition of less-polar silicon-containing films. Moreover, with an increased OMCTS carrier gas flow rate, the surface conductivity of the EP increases by two orders of magnitude, which is directly related to the appearance of shallow traps in the dielectric surface after Ar/OMCTS plasma treatment. Results show that the trap depth of the electron decreases from 1.21 to 0.99 eV post-treatment, with the OMCTS fragments becoming shallow trap points for charge detrapping and transportation processes. Moreover, the addition of a controlled amount of OMCTS increases the plasma discharge intensity, promotes silicon film deposition, and thus significantly improves the insulation and wettability performance, with higher flashover voltages and water contact angles (WCA). By contrast, excessive addition of OMCTS inhibits the plasma discharge due to the absorption and consumption of energetic electrons by OMCTS molecules. Quantum chemistry calculations are further developed to explore the mechanisms of plasma-induced surface modifications. Overall, the proposed plasma polymerization strategy offers a promising fabrication technique and provides guiding insights into the fabrication of nanocomposite dielectric materials in electrical engineering.

Minimizing the breakdown voltage and discharge current required to initiate direct in-liquid discharges, thus lowering power-source requirements and avoiding electrode ablation, is crucial for industrial applications of in-liquid plasmas. Here we demonstrate such considerable reductions by employing movable electrodes, without changing the electrode configuration or increasing the system complexity. The new mechanism is based on electrostatic electrode attraction resulting in a reduction in the discharge spacing by up to 6 times and facilitating a plasma initiation at lower breakdown voltages. The accumulated charges consumed by the discharge revert the electrodes to the initial positions, forming a gliding arc between the enlarged gaps and thus inhibiting current increases and electrode ablation.

Hybrid catalytic systems are poised to maximize the efficiency of energy conversion. When coupling heat with visible light or plasma sources, known thermally active catalysts are commonly used. The question becomes whether adapting thermally activated catalysts to hybrid energy systems is the ideal strategy. Differences in reaction pathways, including how the energy is exchanged within hybrid systems, mean new catalyst design approaches are needed. To enable a leap forward in designing hybrid systems and accelerate effective plasma/light catalyst development, there is a need to take two steps back to (i) revise the current strategies used to design appropriate catalysts and (ii) identify the criteria critical to regulating system behavior. Spotlighting carbon dioxide valorization, current routes to catalyst design for hybrid systems are evaluated. As these systems are playing an ever-increasing role in a clean energy future, catalyst design strategies involving ongoing retrospection and realignment toward prevailing energy coupling/conversion mechanisms are discussed to facilitate the leap forward.

Antibiotics have been extensively used as pharmaceuticals for diverse applications. However, their overuse and indiscriminate discharge to water systems have led to increased antibiotic levels in our aquatic environments, which poses risks to human and livestock health. Non-thermal plasma water. However, the issues of process scalability and the mechanisms towards understanding the plasma-induced degradation remain. This study addresses these issues by coupling a non-thermal plasma jet with a continuous flow reactor to reveal the effective mechanisms of amoxicillin degradation. Four industry-relevant feeding gases (nitrogen, air, argon, and oxygen), discharge voltages, and frequencies were assessed. Amoxicillin degradation efficiencies achieved using nitrogen and air were much higher compared to argon and oxygen and further improved by increasing the applied voltage and frequency. The efficiency of plasma-induced degradation depended on the interplay of hydrogen peroxide (H2O2) and nitrite (NO2−), validated by mimicked chemical solutions tests. Insights into prevailing degradation pathways were elucidated through the detection of intermediate products by advanced liquid chromatography-mass spectrometry.

Background New and sustainable food processing platforms are urgently needed to address global food safety and preservation challenges. Nonthermal plasma discharges generated within the food packaging, referred to as the in-package plasma, is a highly promising approach. The in-package plasma technique is very effective for bacterial and sporal sterilization with limited thermal and adverse effects on food quality while requiring low energy inputs and no added potentially hazardous food preservatives. Scope and approach This review provides insights into the fundamental mechanisms of food preservation based on the in-package plasma in diverse processing configurations and packaging gas chemistries. The current and emerging state-of-the-art in-package plasma-based food applications and the prevailing microbiological inactivation mechanisms are critically examined. The potential effects on various nutritional, quality attributes and chemical safety of different food products during shelf life are discussed. Key findings and conclusions In-package plasma technology can be utilized to ensure microbial safety, maintain nutritional quality, and prevent cross-contamination of food products. Studies have shown that the in-package plasma effectively inactivates pathogenic microorganisms and inhibits their growth while preserving the quality of fresh and minimally processed foods during shelf life. To overcome the common limitations of current in-package plasma methods arising due to oxidation of lipids and potential packaging material modification by the reactive species, using oxygen-reduced atmospheres in combination with advanced biopolymer materials for plasma packaging are envisaged. Finally, recommendations and directions for future studies and applications are outlined to address the scientific and engineering challenges of this promising food preservation technology.

Cellulose is the most abundant biopolymer on Earth, which is synthesized by plants, bacteria, and animals, with source-dependent properties. Cellulose containing beta-1,4-linked D-glucoses further assembles into hierarchical structures in microfibrils, which can be processed to nanocellulose with length or width in the nanoscale after a variety of pretreatments including enzymatic hydrolysis, TEMPO-oxidation, and carboxymethylation. Nanocellulose can be mainly categorized into cellulose nanocrystal (CNC) produced by acid hydrolysis, cellulose nanofibrils (CNF) prepared by refining, homogenization, microfluidization, sonification, ball milling, and the aqueous counter collision (ACC) method, and bacterial cellulose (BC) biosynthesized by the Acetobacter species. Due to nontoxicity, good biodegradability and biocompatibility, high aspect ratio, low thermal expansion coefficient, excellent mechanical strength, and unique optical properties, nanocellulose is utilized to develop various cellulose nanocomposites through solution casting, Layer-by-Layer (LBL) assembly, extrusion, coating, gel-forming, spray drying, electrostatic spinning, adsorption, nanoemulsion, and other techniques, and has been widely used as food packaging material with excellent barrier and mechanical properties, antibacterial activity, and stimuli-responsive performance to improve the food quality and shelf life. Under the driving force of the increasing green food packaging market, nanocellulose production has gradually developed from lab-scale to pilot- or even industrial-scale, mainly in Europe, Africa, and Asia, though developing cost-effective preparation techniques and precisely tuning the physicochemical properties are key to the commercialization. We expect this review to summarise the recent literature in the nanocellulose-based food packaging field and provide the readers with the state-of-the-art of this research area., QC 20221101