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In advancing aqueous zinc‐ion batteries (AZIBs) toward commercial viability, vanadium (V)‐based cathodes are pivotal, offering broad redox ranges, and compatibility with water's electrochemical limits. Despite their great potentials, V‐based cathodes face challenges in transitioning from lab to commercialization. Defect engineering is exploited as a pivotal technique that endows the cathodes with unexpected physical and chemical properties to break the intrinsic bottleneck and, in turn, enhance their electrochemical performances. This review delves into the role of defect engineering on V‐based materials, underscoring its potential in mitigating the critical challenges. It starts by encapsulating the current characteristics of V‐based cathodes in AZIBs. Research efforts related to various defects, such as oxygen vacancies, cation vacancies, cationic doping, anionic doping, water intercalation, and lattice disorders/amorphization, are then rationalized and discussed. The fabrication and characterization techniques of defect engineering are also summarized. By integrating the conclusions from existing works and tailoring defect engineering strategies, a few perspectives are provided for systematically employing defect engineering to pave the way for a more efficient transition of these promising materials from laboratory breakthroughs to commercially viable energy storage solutions. [ABSTRACT FROM AUTHOR]

Ever‐increasing emissions of anthropogenic carbon dioxide (CO2) cause global environmental and climate challenges. Inspired by biological photosynthesis, developing effective strategies NeuNlto up‐cycle CO2 into high‐value organics is crucial. Electrochemical CO2 reduction reaction (CO2RR) is highly promising to convert CO2 into economically viable carbon‐based chemicals or fuels under mild process conditions. Herein, mesoporous indium supported on multi‐walled carbon nanotubes (mp‐In@MWCNTs) is synthesized via a facile wet chemical method. The mp‐In@MWCNTs electrocatalysts exhibit high CO2RR performance in reducing CO2 into formate. An outstanding activity (current density −78.5 mA cm−2), high conversion efficiency (Faradaic efficiency of formate over 90%), and persistent stability (~30 h) for selective CO2‐to‐formate conversion are observed. The outstanding CO2RR process performance is attributed to the unique structures with mesoporous surfaces and a conductive network, which promote the adsorption and desorption of reactants and intermediates while improving electron transfer. These findings provide guiding principles for synthesizing conductive metal‐based electrocatalysts for high‐performance CO2 conversion. [ABSTRACT FROM AUTHOR]

The combined application of ultrasound (US) and plasma microbubble (PMB) is a promising technology against glioblastoma (GBM). Here, we determined the effects of US and PMB (alone and combined) on U‐251 MG GBM and A431 epidermoid carcinoma spheroids under different conditions. The synergistic treatment of US‐ and PMB‐induced tumor sphere cell death in a time‐, dose‐, treatment frequency‐, and reactive oxygen species dependent manner, while multiple treatments augmented this effect. Synergistic treatments significantly reduced three‐dimensional GBM spheroid regrowth and cell proliferation while inducing cytotoxicity, spheroid shrinkage, and damage to the tumor microenvironment. PMB‐induced cytotoxicity throughout the tumor sphere, likely via long‐lived reactive oxygen and nitrogen species (H2O2, NO2−, and NO3−) and other reactive species. [ABSTRACT FROM AUTHOR]

Sustainable ammonia synthesis at ambient conditions that relies on renewable sources of energy and feedstocks is globally sought to replace the Haber–Bosch process. Here, using nitrogen and water as raw materials, a nonthermal plasma catalysis approach is demonstrated as an effective power‐to‐chemicals conversion strategy for ammonia production. By sustaining a highly reactive environment, successful plasma‐catalytic production of NH3 was achieved from the dissociation of N2 and H2O under mild conditions. Plasma‐induced vibrational excitation is found to decrease the N2 and H2O dissociation barriers, with the presence of matched catalysts in the nonthermal plasma discharge reactor contributing significantly to molecular dissociation on the catalyst surface. Density functional theory calculations for the activation energy barrier for the dissociation suggest that ruthenium catalysts supported on magnesium oxide exhibit superior performance over other catalysts in NH3 production by lowering the activation energy for the dissociative adsorption of N2 down to 1.07 eV. The highest production rate, 2.67 mmol gcat.−1 h−1, was obtained using ruthenium catalyst supported on magnesium oxide. This work highlights the potential of nonthermal plasma catalysis for the activation of renewable sources to serve as a new platform for sustainable ammonia production. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate whether sonoporation of cancer cells using ultrasound (US) technology could enhance the anticancer effects of cold atmospheric plasma. US‐induced transient sonoporation of cancer cells with little to no cytotoxicity observed on the cell lines tested. Synergistic effects of US were observed when combined with both direct and indirect cold atmospheric plasma. These cytotoxic effects were dependent on reactive species production. To the best of our knowledge that is the first time that the effects of those two nonthermal technologies were evaluated in cancer cells, demonstrating a promising combined strategy for cancer therapies, particularly for those with penetration limitations, such as glioblastoma. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effects of a pin‐to‐plate cold atmospheric plasma (CAP) on U‐251 MG three‐dimensional (3D) glioblastoma spheroids under different conditions. 3D tumorspheres showed higher resistance to the CAP treatment compared to 2D monolayer cells. A single CAP treatment was able to induce cytotoxicity, while multiple CAP treatments augmented this effect. CAP was also able to induce cytotoxicity throughout the tumoursphere, and we identified that reactive oxygen species (ROS) plays a major role, while H2O2 plays a partial role in CAP‐induced cytotoxicity in tumourspheres. We conclude that ROS‐dependent cytotoxicity is induced uniformly throughout glioblastoma and epidermoid tumourspheres by direct CAP treatment. [ABSTRACT FROM AUTHOR]

A large gap pin‐to‐plate, atmospheric‐pressure plasma reactor is demonstrated as means of in vitro study of plasma species interactions with cell cultures. By employing optical emission and optical absorption spectroscopy, we report that the pin‐to‐pate plasma array had an optimal discharge frequency for cell death of 1000 Hz in ambient air for the target cancer cell line, human glioblastoma multiform (U‐251MG). The detected plasma chemistry contained reactive oxygen and nitrogen species including OH, N2, N2+ and O3. We show that by varying the plasma discharge frequency, the plasma chemistry can be tailored to contain up to 8.85 times higher levels of reactive oxygen species (ROS) as well as a factor increase of up to 2.86 for levels of reactive nitrogen species (RNS). At higher frequencies, ROS are more dominant than RNS, which allows for a more dynamic and controlled environment for sample study without modifying the inducer gas conditions. When used for treatment of culture media and cell cultures, variation of the plasma discharge frequency over the range 1000–2500 Hz demonstrated a clear dependence of the responses, with the highest cytotoxic responses observed for 1000 Hz. We propose that the reactor offers a means of studying plasma–cell interactions and possible cofactors such as pro‐drugs and nanoparticles for a large volume of samples and conditions due to the use of well plates. [ABSTRACT FROM AUTHOR]

A plasma's working gas is a significant factor affecting their discharge characteristics and the induced chemistries during plasma–water interactions. However, the effects on the discharge mode and discharge stability have not been fully investigated. This study focuses on the discharge mode transition and stability with nitrogen and oxygen gases. Compared with the oxygen discharge, the nitrogen discharge remained stable over a larger voltage range and long duration time. A diffuse mode discharge had better stability and lower plasma activity for both nitrogen and oxygen gases, whereas a transient spark mode in nitrogen and filament mode in oxygen had lower stability but a higher plasma activity. This study improves the understanding of the physicochemical processes of plasma–water interactions. [ABSTRACT FROM AUTHOR]

In this study, we demonstrate that atmospheric air plasma bubbles are an effective, energy‐efficient, residue‐free alternative to current decontamination techniques. Five to fifteen minutes of plasma‐bubble treatments of inoculated chicken skin led to a significant reduction in colony‐forming units (CFUs). We show that the activation efficiency is dependent on the plasma discharge frequency, with a higher one (2,000 Hz) leading to a higher CFU reduction (1.4 log) as compared with a lower (0.3 log) reduction at 1,000 Hz. Scanning electron microscopy pictures of treated bacteria reveal damage to the cells. An evaluation of the physicochemical properties of the generated plasma‐activated water revealed an increase in conductivity and in ozone, nitrite, nitrate, hydroxyl, and peroxide concentrations with higher frequencies, all contributing to the observed antimicrobial effect. [ABSTRACT FROM AUTHOR]

Crystallization control can be improved through real‐time monitoring technologies. Here, a workflow is demonstrated on rapid batch cooling crystallization of L‐glutamic acid. First, in situ images were generated using video microscopy sensors and analyzed, by employing a single, rapid macro code to extract particle data descriptors. A binning procedure (over time) was performed, where every data point represented the counts of particles within a specific size or shape range per 100 images. This binning method was found more informative in tracking of the populations compared to whole image averages or individual particle datapoints. This study provides a step‐by‐step guide towards improving mechanistic modeling, control via feedback, automation, and continuous manufacturing for Industry 4.0. [ABSTRACT FROM AUTHOR]

Conversion of renewable biomass by time‐ and energy‐efficient techniques remains an important challenge. Herein, plasma catalytic liquefaction (PCL) is employed to achieve rapid liquefaction of microalgae under mild conditions. The choice of the catalyst affects both the liquefaction efficiency and the yield of products. The acid catalyst is more effective and gave a liquid yield of 73.95 wt % in 3 min, as opposed to 69.80 wt % obtained with the basic catalyst in 7 min. Analyses of the thus‐formed products and the processing environment reveal that the enhanced PCL performance is linked to the rapid increase in temperature under the effect of plasma‐induced electric fields and the generation of large quantities of reactive species. Moreover, the obtained solid residue can be simply upgraded to a carbon product suitable for supercapacitor applications. Therefore, the proposed strategy may provide a new avenue for fast and comprehensive utilization of biomass under benign conditions. [ABSTRACT FROM AUTHOR]

BACKGROUND Inactivation of Escherichia coli, suspended in McIlvaine buffer, was investigated by the application of radio frequency electric field (RFEF) under single‐stage, multi‐stage and recirculation flow configurations using a parallel‐plate treatment chamber. Changes in the survival fraction were correlated, through predictive microbiology, as a function of key process parameters: electric field strength, temperature, time and flow rate, as well as the intrinsic media properties: pH and electrical conductivity. Various empirical models, including Hülsheger, Peleg, Geeraerd and Weibull were compared with mechanistic models, such as the first‐order exponential decay and the two‐term exponential models. Mechanistic models were employed to formulate reactor models by performing differential mass balances over the inactivation chambers, with plug‐flow‐reactor (PFR) assumption for single‐ and multi‐stage configurations, and differential PFR for recirculation configuration. RESULTS: The single‐stage configuration with variable flow rate was proven unsuitable for kinetic studies. Nonlinear logarithmic inactivation profiles were observed with multi‐stage and recirculation. The two‐term exponential mechanistic model effectively explained the kinetics of inactivation. Treatment chambers were successfully modelled mechanistically with reaction engineering principles. Common kinetic constants fitted the experimental data for all flow configurations. The intrinsic properties of media also influenced process kinetics. CONCLUSIONS: The presence of variable resistances amongst microbial population adds nonlinearity in RFEF processing with the extension of the treatment time. The research showed that unlike empirical models, the mechanistic approach can explain the complex inactivation behaviour for all flow configurations. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

This work provides an insight into the generation of excited nitrogen species by allowing noble gases to interact both with one another and ambient air. He and Ar were utilized to generate the optimum selectivity process to create reactive nitrogen species. An optimum setting for the generation of excited molecular nitrogen species, based on their excited energy levels, was obtained when using a mixture of Ar‐He at a ratio of 10:1. At that point, when a voltage of 27 kV is applied to the system, it reached the maximum efficiency for selectivity processes to occur which allowed for a greater non‐radiative transfer of energy through the mixture of noble gas atoms and into the molecular nitrogen present in ambient air. [ABSTRACT FROM AUTHOR]

Atmospheric air plasma has previously been shown to be a novel and effective method for biofilm eradication. Here we study the effects of plasma on both microbial inactivation and induced structural modification for forming biofilms. New structures are created from aggregates of extracellular polysaccharides and dead bacterial cells, forming a protective and resilient matrix in which the remaining living cells grow and reproduce under proper growth conditions. The new colonies are found to be more resilient in this state, reducing the efficacy of subsequent plasma treatment. We verify that the observed effect is not caused by chemicals produced by plasma reactive species, but instead by the physical processes of drying and convection caused by the plasma discharge. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the impact of nonthermal plasma (NTP) technology on key nutritional and functional food components is of paramount importance for the successful adoption of the technology by industry. NTP technology (NTPT) has demonstrated marked antimicrobial efficacies with good retention of important physical, chemical, sensory, and nutritional parameters for an array of food products. This paper presents the influence of NTPT on selected functional food components with a focus on low‐molecular‐weight bioactive compounds and vitamins. We discuss the mechanisms of bioactive compound alteration by plasma‐reactive species and classify their influence on vitamins and their antioxidant capacities. The impact of NTP on specific bioactive compounds depends both on plasma properties and the food matrix. Induced changes are mainly associated with oxidative degradation and cleavage of double bonds in organic compounds. The effects reported to date are mainly time‐dependent increases in the concentrations of polyphenols, vitamin C, or increases in antioxidant activity. Also, improvement in the extraction efficiency of polyphenols is observed. The review highlights future research needs regarding the complex mechanisms of interaction with plasma species. NTP is a novel technology that can both negatively and positively affect the functional components in food. [ABSTRACT FROM AUTHOR]

The potential of cold plasma as a food processing aid has been demonstrated for a range of processes and products. The potential applications of plasma technology are extensive and include microbial decontamination, pest control, toxin elimination, food and package functionalisation and many others. However, studies reported to date have principally been at laboratory scale. This paper discusses the status and challenges of transferring the technology to the industry. The major challenges discussed for adoption of atmospheric plasma as a food processing tool by industry are (1) demonstration of product/process specific efficacies; (2) development of process compatible technology designs and scale‐up; (3) effective process control and validation; (4) regulatory approval; and (5) consumer acceptance. [ABSTRACT FROM AUTHOR]

Plasma-activated liquids (PAL) attract increasing interest with demonstrated biological effects. Plasma exposure in air produces stable aqueous reactive species which can serve as chemical diagnostics of PAL systems. Here, we tailor aqueous reactive species inside plasma-activated water (PAW) through treating water with AC air spark and glow discharges in contact with water. Chemical probing demonstrated species specificity between two types of PAW. Spark discharge PAW contains [ABSTRACT FROM AUTHOR]

Fructooligosaccharides ( FOS) are among the main carbohydrates with prebiotic activity, and they are the most applied functional carbohydrate ingredient in the food industry. FOS are known to hydrolyse when subjected to thermal processing, thus partially losing its functional properties. In this study, we evaluate whether three nonthermal technologies are suitable for processing FOS regarding its stability after processing. FOS were subjected to ultrasound, high-pressure processing ( HPP) and atmospheric cold plasma ( ACP). The FOS solution, 70 g L−1, was set at a concentration recommended for human intake. The treatments were carried out at operating conditions usually used for microbial inactivation in foods ( HPP at 450 MPa for 5 min; US at 600-1200 W L−1 for 5 min; ACP at 70 kV for 15-60 s). NMR and HPLC analysis of the FOS components showed that ACP, ultrasound and HPP have not induced any significant change on FOS concentration (<2.0%) nor on the degree of polymerisation of the FOS (<3.3%). Contrarily to what is reported for thermal treatments, these nonthermal technologies were considered suitable for FOS processing. [ABSTRACT FROM AUTHOR]

Tomato juice samples were ozonated with control variables of ozone concentration (1.6–7.8 %w/w) and treatment time (0–10 min). Effects of ozone processing variables on quality parameters of pH, oBrix, titratable acidity (TA), cloud value, non-enzymatic browning, colour values ( L*, a*, and b*) and ascorbic acid (AA) content were determined. No significant changes ( P > 0.05) in pH, oBrix, TA, cloud value and Non enzymatic browning (NEB) ( P ≤ 0.05) were found with ozonation. L*, a* and b* colour values were significantly affected by ozone concentration and treatment time. A significant reduction of AA (96 %) was observed at an ozone concentration of 7.8%w/w and a treatment time of 10 min. Results presented in this study indicate that visual colour and nutritional quality is significantly affected during ozone processing. Thus, the effects of ozonation on the nutritional properties of tomato juice should be considered by processors prior to its adoption as a preservation technique. [ABSTRACT FROM AUTHOR]

Freshly squeezed orange juice was sonicated at various amplitude levels (40%, 70%, 100%), treatment times (2, 6 and 10 min) at a constant frequency of 20 kHz. Samples were stored for periods of up to 30 days at 10 °C. The combined effect of amplitude level, treatment time and storage period on pH, oBrix, titratable acidity, colour values ( L*, a*, b*), non-enzymatic browning (NEB), cloud value and ascorbic acid content were investigated. Second order polynomial models were employed to investigate the effect of independent variables. No significant differences ( P < 0.05) in oBrix and titratable acidity were observed. Significant changes were observed in juice pH and colour values. During storage NEB increased while both cloud value and ascorbic acid content decreased. Predictive models developed for colour values, cloud value, NEB and ascorbic acid content were highly significant and were closely correlated to experimental data. Degradation mechanisms are proposed for the key quality parameters. [ABSTRACT FROM AUTHOR]

Recent reports indicate that atmospheric cold plasma (ACP) treatment of seeds can enhance their germination, however, the mechanisms of action are not yet entirely clear. In the present work, we report on the effects of plasma treatment on wheat seed germination and seedling growth. Additionally, changes in the surface chemistry and characteristics of the wheat seeds exposed to plasma were investigated. Treatments of 30–60 s significantly enhanced the germination rate and showed positive effects on seedling growth. ACP resulted in changes of seed surface and chemical characteristics including water uptake and contact angle values. Changes in seed pH and total titratable acidity, as well as nitrites, nitrates, and malondialdehyde concentrations were also recorded. [ABSTRACT FROM AUTHOR]

Front Cover: The cold plasma‐based inner‐surface decontamination is of particular relevance to biofouling of pipelines, both industrial and clinical. A helium porous plasma jet based on gas diffuser was designed, with the aim of decontaminating inner surfaces of relevant contaminated structures. The porous plasma jet operates with discharge modes in ambient air and inside vessels. Its decontamination capacity is demonstrated by inactivation efficacy of Pseudomonas aeruginosa biofilm as a well characterised biofilm model. Further details can be found in the article by Peng Lu, Dana Ziuzina, Patrick J. Cullen, and Paula Bourke (e1800055). [ABSTRACT FROM AUTHOR]

We present a helium porous plasma jet based on gas diffuser, designed with the aim of decontaminating inner surfaces of contaminated structures, e.g., pipes. The porous plasma jet operates with three discharge modes in ambient air and inside a vessel. Its decontamination capacity is demonstrated by evaluating the inactivation efficacy of biofilm form of Pseudomonas aeruginosa, adherent to inner surface of a glass vial. Plasma treatments for 5 min with filament mode and double region helium discharge mode reduced bacterial numbers by 2.4 and 2.5 Log10 CFU/ml. Plasma treatment with double region air‐like discharge mode was the most effective, reducing bacterial cells by 4.5 Log10 CFU/ml, which demonstrates porous plasma jet could provide an efficient approach for inner surface decontamination. A helium porous plasma jet has been presented. With the proper discharge mode, it significantly inactivates Pseudomonas aeruginosa biofilm adherent to the inner surface of a glass vial by greater than 4 Log10 CFU/ml. The porous plasma jet presented can provide an efficient alternative for the inner surface sterilization in relevant sectors, such as medical device, food and pharmacy industries. [ABSTRACT FROM AUTHOR]