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Cold plasma treatment is an innovative technology in the food processing and preservation sectors. It is primarily employed to deactivate microorganisms and enzymes without heat and chemical additives; hence, it is often termed a "clean and green" technology. However, food quality and safety challenges may arise during cold plasma processing due to potential chemical interactions between the plasma reactive species and food components. This review aims to consolidate and discuss data on the impact of cold plasma on the chemical constituents and physical and functional properties of major food products, including dairy, meat, nuts, fruits, vegetables, and grains. We emphasize how cold plasma induces chemical modification of key food components, such as water, proteins, lipids, carbohydrates, vitamins, polyphenols, and volatile organic compounds. Additionally, we discuss changes in color, pH, and organoleptic properties induced by cold plasma treatment and their correlation with chemical modification. Current studies demonstrate that reactive oxygen and nitrogen species in cold plasma oxidize proteins, lipids, and bioactive compounds upon direct contact with the food matrix. Reductions in nutrients and bioactive compounds, including polyunsaturated fatty acids, sugars, polyphenols, and vitamins, have been observed in dairy products, vegetables, fruits, and beverages following cold plasma treatment. Furthermore, structural alterations and the generation of volatile and non‐volatile oxidation products were observed, impacting the color, flavor, and texture of food products. However, the effects on dry foods, such as seeds and nuts, are comparatively less pronounced. Overall, this review highlights the drawbacks, challenges, and opportunities associated with cold plasma treatment in food processing. [ABSTRACT FROM AUTHOR]

There are a number of cutting-edge techniques implemented in the germination process, including high pressure processing, ultrasonic, ultraviolet, light, non-thermal plasma, magnetic feld, microwave radiation, electrolyzed oxidizing water, and plasma activated water. The infuence of these technological advances on seed germination procedure is addressed in this review. The use of these technologies has several benefts, including the enhancement of plant growth rate and the modulation of bioactive chemicals like ABA, protein, and peroxidase concentrations, as well as the suppression of microbial development. Microgreens’ positive health efects, such as their antioxidant, anticancer, antiproliferative/pro-oxidant, anti-obesity, and anti-infammatory properties are extensively reviewed. The phytochemical and bioactive components of microgreens were investigated, including the concentrations of vitamin K, vitamin C, vitamin E, micro and macro nutrients, pro-vitamin A, polyphenols, and glucosinolates. Furthermore, the potential commercial uses of microgreens, as well as the current market transformation and prospects for the future are explored. [ABSTRACT FROM AUTHOR]

The hydrogenation of metal nanoparticles provides a pathway toward tuning their combustion characteristics. Metal hydrides have been employed as solid-fuel additives for rocket propellants, pyrotechnics, and explosives. Gas generation during combustion is beneficial to prevent aggregation and sintering of particles, enabling a more complete fuel utilization. Here, we discuss a novel approach for the synthesis of magnesium hydride nanoparticles based on a two-step aerosol process. Mg particles are first nucleated and grown via thermal evaporation, followed immediately by in-flight exposure to a hydrogen-rich low-temperature plasma. During the second step, atomic hydrogen generated by the plasma rapidly diffuses into the Mg lattice, forming particles with a significant fraction of MgH2. We find that hydrogenated Mg nanoparticles have an ignition temperature that is reduced by ∼200 °C when combusted with potassium perchlorate as an oxidizer, compared to the non-hydrogenated Mg material. This is due to the release of hydrogen from the fuel, jumpstarting its combustion. In addition, characterization of the plasma processes suggests that a careful balance between the dissociation of molecular hydrogen and heating of the nanoparticles must be achieved to avoid hydrogen desorption during production and achieve a significant degree of hydrogenation.

[Display omitted] • The dip-coated GO on NF was in situ reduced and N -doped by N 2 plasma method. • PNrGO as the conductive substrate endowed NiCo-LDH growth. • NiCo-LDH@PNrGO/NF was employed as the redox mediator for decoupled water electrolysis. • Redox mediator exhibited high electrochemical capacitance and buffering capacity. Although the recent emergence of decoupled water electrolysis prevents typical H 2 /O 2 mixing, the further development of decoupled water electrolysis has been confined by the lack of reliable redox mediator (RM) electrodes to support sustainable H 2 production. As energy storage electrodes, layered double hydroxides (LDHs) possess inherently poor conductivity/stability, which can be improved by growing LDHs on graphene substrates in situ. The proper modification of the graphene surface structure can improve the electron transport and energy storage capacity of composite electrodes, while current methods are usually cumbersome and require high temperatures/chemical reagents. Therefore, in this study, dip coating was adopted to grow graphene oxide (GO) on nickel foam (NF). Then, the GO was reduced using nonthermal plasma (NTP) to reduced GO (rGO) in situ while simultaneously implementing N doping to obtain plasma-assisted N -doped rGO on NF (PNrGO/NF). The uniform conductive substrate ensured the subsequent growth of less-aggregated NiCo-LDH nanowires, which improved the conductivity and energy storage capacity (5.93 C/cm2 at 5 mA/cm2) of the NiCo-LDH@PNrGO/NF. For the decoupled system, the composite RM electrode exhibited a high buffering capacity for 1300 s during the decoupled H 2 /O 2 evolution, and in the conventional coupled system, the necessary input voltage of 1.67 V was separated into two lower ones, 1.42/0.33 V for H 2 /O 2 evolutions, respectively. Simultaneously, the RM possessed outstanding redox reversibility and structural stability during long-term cycling. This work could offer a feasible strategy for using NTP to synthesize excellent RM electrodes for application to decoupled water electrolysis. [ABSTRACT FROM AUTHOR]

Aim The main objective of the study was to develop and validate a model for the growth of Aspergillus brasiliensis on surfaces, specifically on agar culture medium. An additional aim was to determine conditions for complete growth inhibition of this micromycete using two different nonthermal plasma (NTP) sources. Methods and results The developed model uses two key parameters, namely the growth rate and growth delay, which depend on the cultivation temperature and the amount of inoculum. These parameters well describe the growth of A. brasiliensis and the effect of NTP on it. For complete fungus inactivation, a single 10-minute exposure to a diffuse coplanar surface barrier discharge was sufficient, while a point-to-ring corona discharge required several repeated 10-minute exposures at 24-h intervals. Conclusions The article presents a model for simulating the surface growth of A. brasiliensis and evaluates the effectiveness of two NTP sources in deactivating fungi on agar media. [ABSTRACT FROM AUTHOR]

Cold‐chain transport is a crucial cross‐regional transmission pathway for severe acute respiratory syndrome coronavirus 2 and other microorganisms. In this study, the mode‐combination method is adopted for sterilization in a 1.138 m3 freezer by mixing effluent gases of NOx and O3 mode air discharges. The mixed gas can effectively inactivate Staphylococcus aureus in 10 mm ice within 3 h, which significantly surpasses O3 gas. Moreover, the inactivation effect of the mixed gas can penetrate deep into ice, contrasting with the surface effect of O3 gas. This disparity is linked to the difference in penetration depth of strong oxidizing long‐lived reactive species. This study validates the sterilization efficacy of cold atmospheric plasma in practical cold‐chain environment, critical for curbing infectious disease transmission. [ABSTRACT FROM AUTHOR]

A nonthermal, pulsed spark discharge is applied to three polymer powders in Ar and Ar–H2 ${{\rm{H}}}_{2}$ gas mixtures. Hydrogen is introduced to assess plasma‐driven decomposition. Gaseous decomposition products, including methane, acetylene, and ethylene, are observed with Fourier‐transform infrared (FTIR). Surface modifications are observed on the residual polymer via attenuated total internal reflection‐FTIR. Time‐averaged rotational, vibrational, and excitation temperatures are characterized in the discharge. The plasma density is found to be around 3×1022 m−3 $3\times 1{0}^{22}\unicode{x0200A}{{\rm{m}}}^{-3}$, with rotational and vibrational temperatures ranging from 1500 to 2200 K and an excitation temperature of 1–2 eV. While spark properties did not change with either gas composition or polymer composition, it was determined that the addition of hydrogen promoted higher concentrations of gaseous phase products (promoting hydrogenolysis). [ABSTRACT FROM AUTHOR]

Viruses can spread through contaminated aerosols and contaminated surface materials, and effective disinfection techniques are essential for virus inactivation. Nonthermal plasma‐generated reactive oxygen and nitrogen species can effectively inactivate the coronavirus. We aim to interpret the coronavirus inactivation level and mechanism of surface interaction with materials with and without dielectric barrier discharge (DBD) plasma treatment. Nonthermal plasma, particularly surface‐type DBD plasma, can inactivate human coronavirus 229E (HCoV‐229E) on porous (paper, wood, mask) and nonporous (plastic, stainless steel, glass, Cu) materials. Virus inactivation was analyzed using a 50% tissue culture infectivity dose (TCID50) using cell line, flow cytometry, and immunofluorescence. Surfaces contaminated with HCoV‐229E were treated at different time intervals (0–5 h) with and without plasma exposure (natural decay in ambient air conditions). HCoV‐229E persistence conformed to the following order: plastic > cover glass > stainless steel > mask > wood > paper > Cu with and without plasma exposure. HCoV‐229E was more stable in plastic, cover glass, and stainless steel in 5 h, and the viable virus titer gradually decreased from its initial log10 order of 6.892 to 1.72, 1.53, and 1.32 TCID50/mL, respectively, under plasma exposure. No virus was observed in Cu after treatment for 5 h. The use of airflow, ambient nitrogen, and argon did not promote virus inactivation. Flow cytometry and immunofluorescence analysis demonstrated a low expression level of spike protein (fluorescence intensity) during plasma treatment and in E and M genes expression compared with the virus control. [ABSTRACT FROM AUTHOR]

The energy state of endosteal implants is dependent on the material, manufacturing technique, cleaning procedure, sterilization method, and surgical manipulation. An implant surface carrying a positive charge renders hydrophilic properties, thereby facilitating the absorption of vital plasma proteins crucial for osteogenic interactions. Techniques to control the surface charge involve processes like oxidation, chemical and topographical adjustments as well as the application of nonthermal plasma (NTP) treatment. NTP at atmospheric pressure and at room temperature can induce chemical and/or physical reactions that enhance wettability through surface energy changes. NTP has thus been used to modify the oxide layer of endosteal implants that interface with adjacent tissue cells and proteins. Results have indicated that if applied prior to implantation, NTP strengthens the interaction with surrounding hard tissue structures during the critical phases of early healing, thereby promoting rapid bone formation. Also, during this time period, NTP has been found to result in enhanced biomechanical fixation. As such, the application of NTP may serve as a practical and reliable method to improve healing outcomes. This review aims to provide an in-depth exploration of the parameters to be considered in the application of NTP on endosteal implants. In addition, the short- and long-term effects of NTP on osseointegration are addressed, as well as recent advances in the utilization of NTP in the treatment of periodontal disease. [ABSTRACT FROM AUTHOR]

In this study, a system of nonthermal plasma that was operated under atmospheric pressure and was powered by argon gas was employed. The particular plasma properties are affected by changes in the Ar gas flow ranges from 0.5 to 2.5 l/min, product by stream of the plasma jet that is utilized. By using the aforementioned method generated from AC and DC. After placing Ar gas as the cathode, which represents the negative pole, flows toward the anode, which is represented by a tiny metal plate of Zn measuring 6 × 1 cm2 in size, with a submerged part of 4 cm2 long, with both types of current employed having a high voltage of 13.5 kV and the frequency of AC was 30 kHz, we measured these variable parameters. It has been shown that when argon flow rises, ionization and plasma glow increase in AC and DC. Thus, when alternating current was utilized, an increase in the plasma properties increased with rose a gas flow ratio of 0.5–2.5 l/min. So the value of electron temperature (Te) increased from 1.49 to 1.84 eV, electron density (ne) also increased from 0.53 × 1018 to 5.40 × 1018 cm−3, fp increased from 0.649 × 1013 to 2.087 × 1013 Hz, while λD reduced from 0.116 × 10^−5 to 0.040 × 10^−5 cm. As for when utilizing DC, the plasma parameters rose with an increase in flow ratio of Ar gas of 0.5–2.5 l/min, thus the value of (Te) elevation of 1.40–1.82 eV, the value of (ne) also elevation of 0.34 × 1018–5.15 × 1018 cm−3, (fp) increased of 0.527 × 1013–2.037 × 1013 Hz, while (λD) reduced of 0.139 × 10^−5–0.041 × 10^−5 cm. The results showed that the AC had a bigger impact on the plasma properties than the DC, as seen by the spectrum peaks identified by a spectrometer. [ABSTRACT FROM AUTHOR]

Nonthermal atmospheric or low-pressure plasma (NTP) can improve the surface characteristics of dental materials without affecting their bulk properties. This study aimed to systematically review the available scientific evidence on the effectiveness of using NTP for the surface treatment of etchable, silica-based dental ceramics before cementation, and elucidate its potential to replace the hazardous and technically demanding protocol of hydrofluoric acid (HF) etching. A valid search query was developed with the help of PubMed's Medical Subject Headings (MeSH) vocabulary thesaurus and translated to three electronic databases: PubMed, Web of Science, and Scopus. The methodological quality of the studies was assessed according to an adapted version of the Methodological Index for Non-Randomized Studies (MINORS). Thirteen in vitro study reports published between 2008 and 2023 were selected for the qualitative and quantitative data synthesis. The implemented methodologies were diverse, comprising 19 different plasma treatment protocols with various device settings. Argon, helium, oxygen, or atmospheric air plasma may significantly increase the wettability and roughness of silicate ceramics by plasma cleaning, etching, and activation, but the treatment generally results in inferior bond strength values after cementation compared to those achieved with HF etching. The technically demanding protocol of plasma-enhanced chemical vapor deposition was employed more commonly, in which the surface deposition of hexamethyl disiloxane with subsequent oxygen plasma activation proved the most promising, yielding bond strengths comparable to those of the positive control. Lack of power analysis, missing adequate control, absence of examiner blinding, and non-performance of specimen aging were common methodological frailties that contributed most to the increase in bias risk (mean MINORS score 15.3 ± 1.1). NTP can potentially improve the adhesive surface characteristics of dental silicate ceramics in laboratory conditions, but the conventional protocol of HF etching still performs better in terms of the resin-ceramic bond strength and longevity. More preclinical research is needed to determine the optimal NTP treatment settings and assess the aging of plasma-treated ceramic surfaces in atmospheric conditions. [ABSTRACT FROM AUTHOR]

ABSTRACT: High CO2 in packages significantly extends microbiological shelf life of poultry meat. Cold plasma is an emerging antimicrobial treatment, which generates various reactive gas species and inactivates microbials effectively. The objective of this study was to explore the potential effects of combining high CO2 package and in-package cold plasma (IPCP) treatments on the quality and safety of raw chicken breast meat. Noninoculated samples and samples inoculated with Campylobacter jejuni and Salmonella Typhimurium were packaged in 0, 30, 70, or 100% CO2 (with make-up gas N2) and treated with IPCP at 70 kV for 3 min. Ozone formation, microbial counts, drip loss, pH, and color were measured. There was no interaction effect between high CO2 package and IPCP on microbial counts, drip loss, and color measurements. IPCP reduced spoilage microbial growth by 0.43 log (from 7.00 log to 6.57 log, P = 0.033) and C. jejuni populations by 0.67 log (from 4.82 log to 4.15 log, P < 0.001) on meat surface but did not affect S. Typhimurium (P = 0.206). Increased CO2 in packages had more effect on spoilage microbial growth (more than 1.5 log from 8.08 log to 6.35 log, P < 0.001) and S. Typhimurium populations (more than 0.5 log from 4.94 log to 4.39 log, P = 0.004) than IPCP but did not affect C. jejuni (P = 0.163). IPCP resulted in increases in changes in L* by 1.67 units (0.70 vs. 2.37, P = 0.016) and a* values by 0.56 units (0.73 vs. 1.29, P < 0.001) and decreases in b* values by 0.91 units (0.46 versus −0.45, P = 0.015). High CO2 levels caused increases in changes in L* values by 4.35 units (−0.82 versus 3.53, P < 0.001) with no effects on a* and b* values (P > 0.05). Data demonstrate that there are no combined effects by high CO2 package and IPCP on meat quality and safety of raw chicken breast meat under our experimental conditions. Either high CO2 package or IPCP can retain microbial quality and safety, even though they may cause changes in appearance of stored chicken breast meat.

The coronavirus disease 2019 (COVID-19) pandemic has greatly stressed the global community, exposing vulnerabilities in the supply chains for disinfection materials, personal protective equipment, and medical resources worldwide. Disinfection methods based on cold atmospheric plasma (CAP) technologies offer an intriguing solution to many of these challenges because they are easily deployable and do not require resource-constrained consumables or reagents needed for conventional decontamination practices. CAP technologies have shown great promise for a wide range of medical applications from wound healing and cancer treatment to sterilization methods to mitigate airborne and fomite transfer of viruses. This review engages the broader community of scientists and engineers that wish to help the medical community with the ongoing COVID-19 pandemic by establishing methods to utilize broadly applicable CAP technologies.

Hydrogen (H 2) is recognized as a viable and environmentally friendly energy source, utilized across various domains, from large-scale chemical energy exports to small-scale power generation in remote areas. However, the storage and distribution costs of H 2 present significant challenges. Ammonia (NH 3) emerges as a carbon-free hydrogen carrier, backed by a robust international transport and storage infrastructure. On-site hydrogen production can be efficiently achieved through NH 3 decomposition, predominantly via thermal catalysis. One innovative approach involves plasma technology, which utilizes NH 3 , alcohols, or hydrocarbons to produce pure hydrogen in plasma reactors. Nonthermal plasma (NTP) in particular, for NH 3 decomposition and H 2 production, has garnered considerable interest owing to its higher energy efficiency than thermal plasma systems. Furthermore, integrating NTP with catalysis, termed plasma-assisted catalysis, creates a synergistic effect, enhancing NH 3 decomposition efficiency for H 2 production through improved plasma-catalyst interactions. Consequently, NTP-catalysis holds the potential to revolutionize NH 3 conversion and utilisation in the future. To date, there have been limited studies on NTP-assisted catalytic NH 3 decomposition. This review article compiles the latest NTP-assisted catalytic NH 3 decomposition methodologies for H 2 production. It delves into the basics of plasma-assisted NH 3 decomposition, including adsorption, desorption, and the synergistic processes during plasma catalysis. Additionally, it examines the impact of NTP on the chemical states and properties of various catalysts and provides a comprehensive analysis of the factors influencing NH 3 -plasma decomposition. • Nonthermal plasma-assisted catalysis NH3 decomposition for COx-free H2 production. • Full NH 3 decomposition achieved at ambient temperature and pressure by applied NTP. • Combining plasma with catalysis has improved the NH3 efficiency decomposition. • NTP catalysis can potentially revolutionize NH3 conversion and utilisation in the future. [ABSTRACT FROM AUTHOR]

Nanoscale metallic titanium (Ti) offers unique energetic and biocompatible characteristics for the aerospace and biomedical industries. A rapid and sustainable method to form purified Ti nanocrystals is still in demand due to their high oxygen affinity. Herein, we report the production of highly purified Ti nanoparticles with a nonequilibrium face center cubic (FCC) structure from titanium tetrachloride (TiCl4) via a capacitively coupled plasma (CCP) route. Furthermore, we demonstrate a secondary H2 treatment plasma as an effective strategy to improve the air stability of a thin layer of nanoparticles by further removal of chlorine from the particle surface. Hexagonal and cubic-shaped Ti nanocrystals of high purity were maintained in the air after the secondary H2 plasma treatment. The FCC phase potentially originates from small-sized grains in the initial stage of nucleation inside the plasma environment, which is revealed by a size evolution study with variations of plasma power input. [ABSTRACT FROM AUTHOR]

When N2/O2 mixture is used for nitrogen fixation (NF), researchers believe that the Zeldovich mechanism is the main pathway for NO formation. However, there is still debate on whether N2 participates in the Zeldovich mechanism through vibrational excitation or electronic excitation of the N2(A) state. This ambiguity has led to uncertainty regarding which type of plasma can achieve higher efficiency. Furthermore, the most significant obstacle to plasma‐assisted NF is the high energy consumption. Gaining a deeper understanding of the energy flow in the discharge process is crucial for improving NF energy efficiency in the future. Therefore, this paper provides an overview of the research on these topics. Finally, various new plasma NF devices reported in recent years will also be discussed. [ABSTRACT FROM AUTHOR]

The interest in nonthermal discharge plasma has recently increased over the last few decades due to the ability to generate new radicals at atmospheric pressure. This paper presents a comprehensive analysis of the dissociation processes and reaction rates of various water vapour samples by dielectric barrier discharge plasma (DBD). The influence of water contamination and the presence of ammonia (NH 3) on hydrogen production from water vapour was investigated. A novel reaction rate expression was proposed to fit the plasma-water vapour experiment results. The hydrogen production and conversion rate of pure reverse osmosis (RO) water samples showed greater results than the contaminated water samples in all experiments at different tested bubbling temperatures. The higher conversion rate was obtained from RO water combined with 1%NH 3 at a bubbling temperature of 50 °C and was 1.17%. The water contamination influenced the generated DBD plasma micro discharges, consequently decreasing the electron collisions, leading to lower water vapour conversion into constituent elements H 2 and O 2. It was also found that the influence of ammonia on the water vapour decomposition was related to the NH 3 concentration. Moreover, the reaction rate showed good agreement with the experimental results. It was observed that the energy efficiencies were obtained at an operating temperature of 50 °C for pure RO, GTW, and CTW water samples enhanced by adding 1%NH 3 , for example, the RO energy efficiency value at a bubbling temperature of 50 °C increased from 0.133% to 1.15% because of more hydrogen was generated. It implies that the water vapour decomposition processes are influenced by the following parameters: input gas temperature, reaction time, plasma power, oven or reactor heating temperature, the separation method, sampling method, and sampling collection time. [Display omitted] • The hydrogen production from various water types by DBD plasma is investigated. • The presence of ammonia enhanced the hydrogen production of water vapour. • The water contamination has a negative effect on the plasma water decomposition. • The new rate equation showed a good agreement with experimental results. [ABSTRACT FROM AUTHOR]

The environmental performance of nonthermal plasma assisted dry reforming of methane (NTP-DRM) for hydrogen production from methane rich natural gas is investigated and compared with the current state of the art steam reforming technology through a cradle-to-gate life cycle assessment (LCA). The NTP-DRM technologies studied in this analysis include dielectric barrier, microwave, and pulsed plasma discharges. Due to the level of technology the study is considered as the prospective LCA of selected types of NTP-DRMs for hydrogen production. Of these, the NTP-DRM using microwave and pulsed plasma presented better environmental performance. The impact categories include midpoints levels applying TRACI 2.1 and AWARE for the water scarcity, using ecoinvent 3.8 and US NETL databases. The scenario analysis regarding carbon dioxide, electricity, and natural gas sources, revealed the highly dependency of NTP-DRMs technologies environmental performance to the energy efficiency of the processes. In terms of steam reforming of methane (SRM) despite the main contribution of steam use in the technology environmental performance, the uncertainty analysis showed higher sensitivity to natural gas input. Investigation showed that using renewable energy sources can have significant improvement regarding NTP-DRMs environmental performance and specifically global warming potential. Accordingly, at their current reactant conversion and product selectivity reaching the energy use of eV per molecule of reactant equal or less than 2, can be a proper target for the studied best case NTP-DRM to make their environmental behavior competitive with the state-of-the-art SRM technologies. • Prospective cradle-to-gate life cycle assessment (LCA) of selected nonthermal plasmas (NTP) for dry reforming of methane (DRM). • Comparative LCA between the NTP-DRM and the current state-of-the-art steam reforming of methane (SRM). • Uncertainty and scenario analysis, with a particular emphasis on critical hotspots. • Assessing NTP-DRM's energy efficiency requirement to make it environmentally acceptable compared to current SRM technologies. [ABSTRACT FROM AUTHOR]

A low‐cost plasma‐chemical hybrid process (PCHP) is proposed for simultaneous NOx and SOx treatment. PCHP can be integrated into existing desulfurization reactors by combining plasma oxidation and chemical reduction. PCHP is applied to glass melting furnace emissions with limited denitration technology, achieving higher removal efficiencies of NO, NOx, and SO2 (43%, 38%, and 28%, respectively) by optimizing reductant spray and installation angles. PCHP also improves fuel consumption, with a 0.04 increase in air ratio reducing energy consumption by 3.6 kL/day (equivalent to 6.6 t(CO2)/day reduction). In addition, PCHP allows for the collection and reuse of treated SO2 as sodium sulfate particles, making it a suitable aftertreatment technology for glass manufacturing exhaust. [ABSTRACT FROM AUTHOR]

Nonthermal plasma (NTP), for the first time, was integrated in glycerol dehydration reaction catalyzed by silicotungstic acid supported on mesoporous silica with argon as the carrier and discharge gas. A range of reaction temperatures (220–320°C) and NTP discharge field strengths (2.06–6.87 kV/cm) were studied for the individual and interactive effects regarding the glycerol conversion and product selectivity. Results showed that the presence of NTP always improved the glycerol conversion, and NTP increased acrolein selectivity if properly conditioned. An optimal condition of 275°C and 4.58 kV/cm NTP field strength achieved a glycerol conversion of 94.4 mol%, acrolein selectivity of 88.0 mol%, with an acrolein yield of 83.1 mol%, representing a 10% improvement in acrolein production over that conducted at the same temperature but without NTP. Results of this study will also have significant implication for other heterogeneously catalyzed dehydration reactions. Simulation of the high‐voltage electric field distribution as function of NTP electrical conductivity and relative permittivity of catalyst materials also offers insight for the future design of reactors and catalysts. [ABSTRACT FROM AUTHOR]

Several regulations on exhaust gases have been introduced to curb hazardous exhaust of volatile organic compounds (VOCs) and particulate matter (PM) from the paint and printing industries. VOCs produce photochemical oxidants and suspended PM such as PM2.5, which is now recognized as a global environmental problem. We assess a nonthermal plasma technique for controlling VOC emissions, especially, propose a wet-type packed-bed plasma reactor to extend the treatment of water-non-soluble VOCs. This paper proposes a wet-type packed-bed plasma reactor to extend the treatment of water-non-soluble VOCs. The proposed technique is evaluated through the simultaneous removal of nanoparticles and toluene at a relatively high flow rate. Simultaneous treatment of the VOCs and nanoparticles using the reactor indicates that the average particle collection efficiency is 94%, and the removal efficiency of 60 ppm toluene is 73% with a gas flow rate of 10 L/min. The resultant byproducts are benzaldehyde (C6H5CHO), benzyl alcohol (C6H5CH2OH), phenol (C6H5OH), ozone, formic acid, and acetic acid, and some are easily dissolved and removed by the sodium hydroxide solution film. A smaller pellet diameter leads to more efficient toluene removal at lower specific energy values, while the ozone concentration does not change. However, the ozone concentration can be greatly suppressed by dissolving the ozone in the alkali solution film. [ABSTRACT FROM AUTHOR]

Plasma pyrolysis of 1,1,2,2-tetrachloroethane was carried out in a liquid phase at a dc source voltage of 100–300 V and a process time of 1–5 h. An increase in the dc voltage from 100 to 300 V led to an increase in the conversion of 1,1,2,2-tetrachloroethane from 21.6 to 71.7 wt % for 1 h with an increase in energy consumption for the transformation of 1,1,2,2-tetrachloroethane from 0.20 to 0.28 kW h/mol. As the process time was increased from 1 to 5 h, the conversion of 1,1,2,2-tetrachloroethane increased from 21.6 to 68.9 wt %, and energy consumption increased from 0.20 to 0.33 kW h/mol. Regardless of the conditions of pyrolysis, an increase in the conversion of tetrachloroethane led to a decrease in the yield of tetrachloroethylene and trichloroethylene by a factor of 2–3 due to their conversion into perchlorinated hydrocarbons. [ABSTRACT FROM AUTHOR]

Antibacterial properties and chemical changes of two culture media, Dulbecco's Modified Eagle Medium (DMEM) and Roswell Park Memorial Institute (RPMI), treated by RF‐driven He/O2 plasma jet, were studied using various chemical diagnostics and assessing Escherichia coli inactivation. The antibacterial effect increased with the plasma treatment time and was stronger in RPMI than in DMEM. Formation of organic mono‐ and dichloramines of amino acids in DMEM/RPMI by hypochlorite produced by the reaction of plasma‐generated O atoms with Cl− ions present in culture media were the major causes of the biocidal activity. This behavior was attributed to the action of tertiary chemical products formed by the decay of organic dichloramines. The thiobarbituric acid assay revealed malondialdehyde formation from glucose oxidation as the major component of the media. [ABSTRACT FROM AUTHOR]

Forward feed multilayered perception and central composite rotatable design were used to model the nonthermal plasma (NTP) experimental data in artificial neural network (ANN) and response surface methodology, respectively. The ANN was found to be more accurate in modeling the experimental dataset. The NTP process parameters (voltage and time) were optimized for pineapple juice within the range of 25–45 kV and 120–900 s using an ANN coupled with the genetic algorithm (ANN‐GA). After 176 generations of GA, the ANN‐GA approach produced the optimal condition, 38 kV and 631 s, and caused the inactivation of peroxidase (POD) and bromelain by 87.24% and 51.04%, respectively. However, 100.32% of the overall antioxidant capacity and 89.96% of the ascorbic acid were maintained in the optimized sample with a total color change (ΔE) of less than 1.97 at all plasma treatment conditions. Based on optimal conditions, NTP provides a sufficient level of POD inactivation combined with excellent phenolic component extractability and high antioxidant retention. Furthermore, plasma treatment had an insignificant effect (p > 0.05) on the physicochemical attributes (pH, total soluble solid, and titratable acidity) of juice samples. From the intensity peak of the Fourier‑transform infrared spectroscopy analysis, it was found that the sugar components and phenolic compounds of plasma‐treated juice were effectively preserved compared to the thermal‐treated juice. [ABSTRACT FROM AUTHOR]

This study investigates the effects of nonthermal plasma characteristics on surface treatments of polyvinyl alcohol with various diagnostics such as Raman spectroscopy, work of adhesion, optical emission spectroscopy, and current–voltage measurements. Our findings demonstrate the importance of controlling the plasma's electron temperature and density to achieve the desired surface treatment outcomes. We show that plasma jets with varying electron temperatures are more appropriate for different surface treatments, with high electron temperatures than 1.1 eV suitable for functional group (C═O) insertion abiding macro‐scale surface roughness and low electron temperatures for plasma etching, which increased surface roughness significantly. Plasma electron temperatures between 1.1 and 1.3 eV are best for treatment as higher ones cause bond breaking while lower ones would etch the surface. [ABSTRACT FROM AUTHOR]

Few investigations have tested the practical use of cold plasma as a novel technology to meet the requirements in the plant cell and tissue culture field. To fill the knowledge gap, we intend to respond to the question of whether plasma priming influenced DNA ultrastructure and the production of atropine (a tropane alkaloid) in Datura inoxia. Calluses were treated with the corona discharge plasma at time durations ranging from 0 to 300 s. Significant increases (about 60%) in biomass were observed in the plasma-primed calluses. The plasma priming of calluses enhanced the accumulation of atropine about 2-fold. The plasma treatments increased proline concentrations and soluble phenols. The drastic increases in the activity of the phenylalanine ammonia-lyase (PAL) enzyme resulted from the applied treatments. Likewise, the plasma treatment of 180 s upregulated the expression of the PAL gene by 8-fold. Also, the expression of the ornithine decarboxylase (ODC) and tropinone reductase I (TR I) genes were stimulated by 4.3-fold and 3.2-fold, respectively, in response to the plasma treatment. The putrescine N-methyltransferase gene displayed a similar trend to that of TR I and ODC genes following the plasma priming. Methylation sensitive amplification polymorphism method was employed to explore the plasma-associated epigenetic changes in DNA ultrastructure. The molecular assessment referred to DNA hypomethylation, validating an epigenetic response. This biological assessment study validates the hypothesis that plasma priming of callus is an efficient, cost-effective, and eco-friendly tool to enhance callogenesis efficiency, elicit metabolism, affect gene regulation, and modify chromatin ultrastructure in D. inoxia. [ABSTRACT FROM AUTHOR]

An evaluation of the gaseous species production by the discharge, i.e., discharge chemical activity, is very important for determining its potential for practical applications. In this work, production of gaseous species by the multi-hollow surface dielectric barrier discharge generated in a perforated ceramic substrate with the air-exposed electrode is investigated under conditions of various discharge powers (1–5 W), air flow rates (0.25–2.4 L/min) and air relative humidities (0–80%). Production of ozone O3, nitrous oxide N2O, nitric oxide NO, nitrogen dioxide NO2, dinitrogen pentoxide N2O5 and nitric acid HNO3 is evaluated in terms of concentration (ppm), production yield (g/kWh) and production rate (mg/h). The work demonstrates a critical impact of both air flow rate and relative humidity on prevailing discharge mode ("O3 mode" vs. "NOx mode") and, thus, on overall composition and concentration of produced gaseous species. For low discharge power, the discharge operates in the "O3 mode", when O3, N2O, N2O5 and HNO3 are dominant gaseous products. With the increasing power, the discharge transfers into the "NOx mode", when N2O and HNO3 along with NO and NO2 are mostly produced. In dry air, transition from "O3 mode" to "NOx mode" is found for the specific input energy of 1000–1100 J/L. With an increase of air relative humidity from 20 to 80%, the transition gradually decreases from approximately 600 to 450 J/L, respectively. [ABSTRACT FROM AUTHOR]

An update to the article "Dielectric-barrier Discharges: Their History, Discharge Physics, and Industrial Applications" by Ulrich Kogelschatz from 2003 is given. The research and applications of barrier discharges of the last decades are summarized. In particular, the latest developments in ozone generation, radiation sources, environmental applications and surface treatment are discussed. Topics, which appeared with growing attention after 2003, such as plasma medicine, carbon dioxide chemistry, liquid treatment and airflow control, are also summarized to provide an outlook into the coming years. It can be stated, that this type of gas discharge is still of high scientific and technological relevance. Its wide range of applications made the research more inter- and cross-disciplinary while modern diagnostic and modeling enabled deeper insights in the complex physical and chemical processes. In this sense, the contribution of Ulrich Kogelschatz, who introduced and inspired several generations of researchers in the field, cannot be overstated. [ABSTRACT FROM AUTHOR]

To investigate the effects of different structural parameters in the degradation of o -Dichlorobenzene (o -DCB) by dielectric barrier discharge nonthermal plasma (DBD-NTP) and to explore the optimal reactor structural parameters, experimental investigations were carried out using plasma reactors of different structures. The effects of single and double dielectric, different high-voltage electrode positions, different dielectric thicknesses, different discharge gaps and different discharge lengths on the degradation efficiency, carbon monoxide and carbon dioxide selectivity, carbon balance, and ozone of o -DCB were investigated in the reactor. The results show that single dielectric, external high-voltage electrode and lower dielectric thickness, discharge gap, and longer discharge length favor ozone control and improve o -DCB degradation and carbon monoxide CO2 selectivity as well as carbon balance. [ABSTRACT FROM AUTHOR]

Plasma‐enhanced chemical vapor deposition is a highly promising tool for coating deposition due to its versatility, tunability, low chemical consumption, and cost‐effectiveness, with an increasing scope of deposition methods at both low and atmospheric pressure. Adhering to green chemistry principles, biobased precursors have recently shifted into the focus of research interests. This review gives an overview of the main biogenic substance classes that have been used for the deposition of plasma polymer coatings, including natural oils, terpenes, enzymes, and lactic acid‐based precursors. The common feature of these precursors is not only their biogenic origin, but additionally the manifold properties of the resulting plasma‐deposited thin films, ranging from antimicrobial properties to tunable surface‐wetting characteristics, electrical conductivity, or biodegradability. This combination of unique features makes plasma‐derived polymers based on natural precursors immensely attractive for manifold applications. [ABSTRACT FROM AUTHOR]

Adaptable technologies capable of reducing contaminants in enclosed spaces are needed. The SARS‐CoV‐2 pandemic has highlighted the vulnerability of current systems forcing the adoption of extreme measures, causing a significant socioeconomic impact. Electrohydrodynamic devices are proposed as a competitive solution that allows obtaining a high degree of viral inactivation with a very low generation of chemical compounds and low power consumption, together with the production of an airflow, which makes its implementation in real environments easy. In this study, airborne positive‐strand RNA viruses are treated with nonthermal atmospheric plasma, achieving >3.4‐logR for HCoV‐229E and Bacteriophage‐MS2 and >2.4‐log SARS‐CoV‐2 at 4W, in a single pass, at O3 and NO2 concentrations ≤0.70 ppm. Electrical, fluid‐dynamic, and chemical characterization provides the design rules. [ABSTRACT FROM AUTHOR]

Non-thermal plasma (NTP) has been demonstrated as one of the promising technologies that can degrade volatile organic compounds (VOCs) under ambient condition. However, one of the key challenges of VOCs degradation in NTP is its relatively low mineralization rate, which needs to be addressed by introducing catalysts. Therefore, the design and optimization of catalysts have become the focus of NTP coupling catalysis research. In this work, a series of two-dimensional nanosheet Co-Ni metal oxides were synthesized by microwave method and investigated for the catalytic oxidation of benzene in an NTP-catalysis coupling system. Among them, Co 2 Ni 1 O x achieves 60% carbon dioxide (CO 2) selectivity (S CO2) when the benzene removal efficiency (RE benzene) reaches more than 99%, which is a significant enhancement compared with the CO 2 selectivity obtained without any catalysts (38%) under the same input power. More intriguingly, this S CO2 is also significantly higher than that of single metal oxides, NiO or Co 3 O 4 , which is only around 40%. Such improved performance of this binary metal oxide catalyst is uniquely attributed to the synergistic effects of Co and Ni in Co 2 Ni 1 O x catalyst. The introduction of Co 2 Ni 1 O x was found to promote the generation of acrolein significantly, one of the key intermediates found in NTP alone system reported previously, suggest the benzene ring open reaction is promoted. Compared with monometallic oxides NiO and Co 3 O 4 , Co 2 Ni 1 O x also shows higher active oxygen proportion, better oxygen mobility, and stronger low-temperature redox capability. The above factors result in the improved catalytic performance of Co 2 Ni 1 O x in the NTP coupling removal of benzene. [Display omitted] [ABSTRACT FROM AUTHOR]

Nonthermal plasma (NTP) is an interesting technique regarding improvements of surface properties of polymeric materials. Three polymers are considered in this study, namely polypropylene (PP), polycarbonate (PC) and polyurethane (PU) chosen for their diversity of use in technical applications. An atmospheric pressure plasma jet (APPJ) using air as working gas is constructed for the treatment of polymer specimens with moderate thermal load for different treatment time intervals and at different nozzle-specimen inter distances. PC specimen is found to suffer most from temperature increase, followed by PU then PP which withstand better the heat generated by plasma. After plasma treatment, surface properties of the considered polymers are investigated using water drop analysis, attenuated total reflectance Fourier transform infrared spectroscopy, surface tester profilometer, and reflectance spectrophotometer. Plasma improves surface properties as wettability, work of energy, surface energy, roughness, and dyeability of treated polymer surfaces. Those properties are found to increase with plasma exposure time; showing more pronounced effects on PU followed by PC and PP. This study can guide the decision of using a certain polymer type treated by plasma for achieving specific applications demanding higher performance of the polymeric material to face challenging practical conditions on wettability and dyeability. [ABSTRACT FROM AUTHOR]

The synergetic effect of nonthermal plasma and ZnO nanoparticles (NPs) on the degradation efficiency of methylene blue was investigated. First, the ZnO nanoparticles were synthesized via the hydrothermal route; the spherical nanoparticles had diameters of 30–50 nm, as observed with a scanning electron microscope (SEM), and had hexagonal ZnO lattice structures, which was confirmed by both X-ray diffraction (XRD) and Raman spectroscopy. The X-ray-photoemission spectroscopy confirmed the ZnO composition and the presence of oxygen vacancies; meanwhile, the optical band gap energy was 3.17 eV. The optical emission of plasma radiation confirmed the presence of various active plasma species. Second, it was found that the maximum degradation efficiency of MB after 60 min was 85% in plasma alone and increased to 95% when combined with 0.2 gL−1 ZnO; but this decreased to 75% when ZnO loading increased to 0.4 gL−1. These results clearly show that combining plasma with the right amount of ZnO is a promising advanced oxidation technique as it provides an additional source of hydroxyl radicals and, at the same time, a source of photons that can excite the ZnO catalyst. The degradation mechanism for plasma alone and the plasma in combination with ZnO was presented. [ABSTRACT FROM AUTHOR]

This multi-disciplinary paper aims to provide a roadmap for the development of an integrated, process-intensified technology for the production of H2, NH3 and NH3-based symbiotic/smart fertilizers (referred to as target products) from renewable feedstock with CO2 sequestration and utilization while addressing environmental issues relating to the emerging Food, Energy and Water shortages as a result of global warming. The paper also discloses several novel processes, reactors and catalysts. In addition to the process intensification character of the processes used and reactors designed in this study, they also deliver novel or superior products so as to lower both capital and processing costs. The critical elements of the proposed technology in the sustainable production of the target products are examined under three-sections: (1) Materials: They include natural or synthetic porous water absorbents for NH3 sequestration and symbiotic and smart fertilizers (S-fertilizers), synthesis of plasma interactive supported catalysts including supported piezoelectric catalysts, supported high-entropy catalysts, plasma generating-chemical looping and natural catalysts and catalysts based on quantum effects in plasma. Their performance in NH3 synthesis and CO2 conversion to CO as well as the direct conversion of syngas to NH3 and NH3—fertilizers are evaluated, and their mechanisms investigated. The plasma-generating chemical-looping catalysts (Catalysts, 2020, 10, 152; and 2016, 6, 80) were further modified to obtain a highly active piezoelectric catalyst with high levels of chemical and morphological heterogeneity. In particular, the mechanism of structure formation in the catalysts BaTi1−rMrO3−x−y{#}xNz and M3O4−x−y{#}xNz/Si = X was studied. Here, z = 2y/3, {#} represents an oxygen vacancy and M is a transition metal catalyst. (2) Intensified processes: They include, multi-oxidant (air, oxygen, CO2 and water) fueled catalytic biomass/waste gasification for the generation of hydrogen-enriched syngas (H2, CO, CO2, CH4, N2); plasma enhanced syngas cleaning with ca. 99% tar removal; direct syngas-to-NH3 based fertilizer conversion using catalytic plasma with CO2 sequestration and microwave energized packed bed flow reactors with in situ reactive separation; CO2 conversion to CO with BaTiO3−x{#}x or biochar to achieve in situ O2 sequestration leading to higher CO2 conversion, biochar upgrading for agricultural applications; NH3 sequestration with CO2 and urea synthesis. (3) Reactors: Several patented process-intensified novel reactors were described and utilized. They are all based on the Multi-Reaction Zone Reactor (M-RZR) concept and include, a multi-oxidant gasifier, syngas cleaning reactor, NH3 and fertilizer production reactors with in situ NH3 sequestration with mineral acids or CO2. The approach adopted for the design of the critical reactors is to use the critical materials (including natural catalysts and soil additives) in order to enhance intensified H2 and NH3 production. Ultimately, they become an essential part of the S-fertilizer system, providing efficient fertilizer use and enhanced crop yield, especially under water and nutrient stress. These critical processes and reactors are based on a process intensification philosophy where critical materials are utilized in the acceleration of the reactions including NH3 production and carbon dioxide reduction. When compared with the current NH3 production technology (Haber–Bosch process), the proposed technology achieves higher ammonia conversion at much lower temperatures and atmospheric pressure while eliminating the costly NH3 separation process through in situ reactive separation, which results in the production of S-fertilizers or H2 or urea precursor (ammonium carbamate). As such, the cost of NH3-based S-fertilizers can become competitive with small-scale distributed production platforms compared with the Haber–Bosch fertilizers. [ABSTRACT FROM AUTHOR]

The nonthermal plasma (NTP) technology is a promising nonthermal technology that can be employed for pasteurization of fruit juice. The effect of NTP on the natural microbiota, namely, aerobic mesophiles (AM), and yeasts and molds (YM) in pineapple juice were examined in the experimental range of 25–45 kV up to 10 min treatment time. At an applied voltage of 45 kV, the AM and YM count reductions of 4.7 and 4.1 log cfu/mL were obtained at the end of the 14‐min treatment. The inactivation kinetics of microbes were attempted to be explained using nonlinear models, including Weibull + tail, Geeraerd, log‐logistic, Coroller, and Cerf. The residual population (Nres) model parameter in the Geeraerd model explained the tailing behavior of microbes. Furthermore, the estimated values for the scale parameter and destruction rate constants were used to describe the sensitive and resistant percentages of the microbial population. According to statistical parameters (R2: 0.978–0.999, RMSE: 0.034–0.277) and validation indicators (accuracy factor: 1.013–1.152, bias factor: 0.985–1.12), all models performed well. Akaike's theory was used to select the best‐fit model, and the Coroller model was shown to be the most accurate one for AM and YM, exhibiting the lowest Akaike increment (Δi = 0). Practical Application: Nonthermal plasma may be used as an alternate nonthermal process for this product in order to meet customer appeal for safe and nutritious juice with minimal processing. The goal of this work was to produce a nutritious and safe pineapple juice by using nonthermal processing. [ABSTRACT FROM AUTHOR]

Nowadays, the majority of the processes used to sterilize disposable medical devices have several drawbacks in terms of safety, energy consumption, and costs. In this work, a sterilization method based on an indirect nonthermal plasma treatment is presented. The main advantages of this method are low environmental impact, absence of harmful chemical compounds' storage, and backward compatibility relative to production, sterilization, and shipping chain. The sterilization of disposable devices, enclosed inside their protective packaging, is achieved by exploiting reactive species produced by a Dielectric Barrier Discharge plasma reactor. Various devices have been subjected to a 2‐h treatment, achieving complete sterilization based on USP and EU‐PHARMA protocols. Pretreatment of carton packaging has been necessary to guarantee a complete sterilization process. [ABSTRACT FROM AUTHOR]

A nonthermal plasma reactor with flowing liquid water and argon gas and a nanosecond pulsed power supply were used to degrade perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) as functions of the pulse repetition frequency and feed concentration. PFOA and PFOS had maximum degradation percentages of 90% and 96%, respectively, at an optimal 2 kHz frequency and feed concentrations of 8.7 ppb and 14.3 ppb, respectively. PFOA and PFOS show the same degradation trends with pulse repetition frequency, although PFOS had a larger amount of de-fluorination. The plasma's efficiency assessed by the degradation of PFOA and PFOS gave the best-case energy yield and EE/O values of 6.6 × 10-10 mol J-1 and 13 kWh m-3 order) for PFOA and 6.7 × 10-1 mol J-1 and 10 kWh m-3 (order) for PFOS, respectively. [ABSTRACT FROM AUTHOR]

Research on nonthermal plasma (NTP) devices first began almost five decades ago. NTP devices discharge electrons, positive ions, ultraviolet light, reactive oxygen species (ROS) and reactive nitrogen species (RNS) at near-physiological temperatures. Advances in plasma science have enabled the manipulation of ROS/RNS irradiation for medical applications. During preclinical stages and in human clinical trials, NTP promotes blood coagulation, eradication of bacterial, viral, and biofilm-related infections, wound healing, and cancer therapy. Previously, tetrachloroaurate (III) increased NTP-induced oxidative stress that was attenuated by reduced and oxidized glutathione, indicating that the presence of interactions between metal ions and biomolecules may modulate biological effects. In this study, using 3,3,5,5-tetramethyl-1-pyrroline-N-oxide (M4PO) as a spin probe in electron paramagnetic resonance (EPR), we observed that the tetrachloroaurate-induced M4PO-X spin adduct was significantly suppressed by ascorbate and α-tocopherol, while dehydroascorbate (DHA) and Trolox were ineffective. Tetrachloroaurate-induced lipid peroxidation, which was measured by 2-thiobarbituric acid-reactive substances (TBARS) in combination with NTP exposure, was suppressed by ascorbate, α-tocopherol and Trolox, while DHA was ineffective. Furthermore, N-acetyl-l-cysteine and dithiothreitol efficiently suppressed tetrachloroaurate-induced M4PO-X spin adduct and lipid peroxidation. LC‒MS/MS analyzes identified hexanal that was significantly elevated by NTP exposure and/or tetrachloroaurate. However, 25 and 250 μM ascorbate did not significantly suppress the formation of aldehydes, such as acetaldehyde, hexanal, nonanal, nonenal, and 4‑hydroxy-2-nonenal. Further studies are warranted to elucidate the redox reactions between metal ions, including gold (III), and biomolecules to expand the possibility of NTP application in medicine and agriculture.

The energy state of endosteal implants is dependent on the material, manufacturing technique, cleaning procedure, sterilization method, and surgical manipulation. An implant surface carrying a positive charge renders hydrophilic properties, thereby facilitating the absorption of vital plasma proteins crucial for osteogenic interactions. Techniques to control the surface charge involve processes like oxidation, chemical and topographical adjustments as well as the application of nonthermal plasma (NTP) treatment. NTP at atmospheric pressure and at room temperature can induce chemical and/or physical reactions that enhance wettability through surface energy changes. NTP has thus been used to modify the oxide layer of endosteal implants that interface with adjacent tissue cells and proteins. Results have indicated that if applied prior to implantation, NTP strengthens the interaction with surrounding hard tissue structures during the critical phases of early healing, thereby promoting rapid bone formation. Also, during this time period, NTP has been found to result in enhanced biomechanical fixation. As such, the application of NTP may serve as a practical and reliable method to improve healing outcomes. This review aims to provide an in-depth exploration of the parameters to be considered in the application of NTP on endosteal implants. In addition, the short- and long-term effects of NTP on osseointegration are addressed, as well as recent advances in the utilization of NTP in the treatment of periodontal disease.

A review is presented to integrate fluid engineering, heat transfer engineering, and plasma engineering treated in the fields of mechanical engineering, chemical engineering, and electrical engineering. A basic equation system for plasma heat transfer fluids is introduced, and its characteristics are explained. In such reviews, generally, the gap between fundamentals and application is large. Therefore, the author attempts to explain the contents from the standpoint of application. The derivation of formulas and basic equations are presented with examples of application to plasmas. Furthermore, the heat transfer mechanisms of equilibrium and nonequilibrium plasmas are explained with reference to the basic equation system and concrete examples of analyses.

Although melanoma accounts for only 5.3% of skin cancer, it results in >75% of skin-cancer-related deaths. To avoid disfiguring surgeries on the head and neck associated with surgical excision, there is a clear unmet need for other strategies to selectively remove cutaneous melanoma lesions. Mohs surgery is the current treatment for cutaneous melanoma lesions and squamous and basal cell carcinoma. While Mohs surgery is an effective way to remove melanomas in situ, normal tissue is also excised to achieve histologically negative margins. This paper describes a novel combination therapy of nonthermal plasma (NTP) which emits a multitude of reactive oxygen species (ROS) and the injection of a pharmaceutical agent. We have shown that the effects of NTP are augmented by the DNA-damaging prodrug, tirapazamine (TPZ), which becomes a free radical only in conditions of hypoxemia, which is often enhanced in the tumor microenvironment. In this study, we demonstrate the efficacy of the combination therapy through experiments with B16-F10 and 1205 Lu metastatic melanoma cells both in vitro and in vivo. We also show the safety parameters of the therapy with no significant effects of the therapy when applied to porcine skin. We show the need for the intratumor delivery of TPZ in combination with the surface treatment of NTP and present a model of a medical device to deliver this combination therapy. The importance of functional gap junctions is indicated as a mechanism to promote the therapeutic effect. Collectively, the data support a novel therapeutic combination to treat melanoma and the development of a medical device to deliver the treatment in situ. [ABSTRACT FROM AUTHOR]

The influence of cold plasma of atmospheric-pressure glow discharge on the surface properties of rice grains has been studied. It has been established that as a result of the impact of nonthermal atmospheric-pressure glow-discharge plasma on the seed surface, the surface becomes hydrophilic and is characterized by a decrease in the contact angle, an increase in surface energy, and enhancement of surface roughness, indicating the effective formation of polar groups on the surface of rice grains. [ABSTRACT FROM AUTHOR]

Objective: The treatment of recalcitrant emerging pollutants is a major concern in wastewater treatment. The purpose of this study was the optimization of emerging recalcitrant pollutant degradation using carbamazepine as a representative pollutant. Investigations of the carbamazepine degradation in wastewater was carried out by manipulating discharge current, air flow rate, and initial concentration to maximize removal efficiency and minimize energy consumption. Method: The study utilized a three‐factor at two levels factorial design with randomized central runs. Discharge current, air flow rate, and initial concentration were the independent variables while to maximize removal efficiency and minimize energy consumption were the response variables. Analysis of variance (ANOVA) was performed on the data. Results: Discharge current, air flow rate, and initial concentration significantly impacted the removal efficiency to different degrees. However, for energy consumption, only current and air flow rate were the significant variables. The highest removal efficiency obtained was 93% ± 4% for 10 and 40 mg/L initial carbamazepine concentration after 10 min of plasma treatment at a current of 0.45 A and no air flow rate. Conclusion: The plasma reactor demonstrated the capability to treat high cyclic organic chemical contaminant concentration in wastewater with possible applications in preconcentrated wastewater remediation. However, there is still room for reactor design optimization. One key area of focus is reducing treatment cost, which may be achieved theoretically, pending further experimental investigation, by introducing an alternating current power supply, which can reduce energy consumption by 50%–60%. Practitioner Points: Discharge current, air flow rate, and initial concentration all influenced the removal efficiency of carbamazepine.For energy consumption, only current and air flow rate were significant variables.Higher currents result in an improved highly reactive species and UV generation.Treatment cost per m3 for the plasma reactor is higher than established technologies.The plasma reactor in the study still requires significant optimization. [ABSTRACT FROM AUTHOR]

Compared to diesel, liquefied natural gas (LNG), often used as an alternative fuel for marine engines, comes with significant advantages in reducing emissions of particulate matter (PM), SOx, CO2, and other pollutants. Promoting the use of LNG is of great significance for achieving carbon peaking and neutrality worldwide, as well as improving the energy structure. However, compared to diesel engines, medium- and high-speed marine LNG engines may produce higher methane (CH4) emissions and also have nitrogen oxide (NOx) emission issues. For the removal of CH4 and NOx from the exhaust of marine LNG engines, the traditional technical route of combining a methane oxidation catalyst (MOC) and an HN3 selective catalytic reduction system (NH3-SCR) will face problems, such as low conversion efficiency and high operation cost. In view of this, the technology of non-thermal plasma (NTP) combined with CH4-SCR is proposed. However, the synergistic mechanism between NTP and catalysts is still unclear, which limits the optimization of an NTP-CH4-SCR system. This article summarizes the synergistic mechanism of NTP and catalysts in the integrated treatment process of CH4 and NOx, including experimental analysis and numerical simulation. And the relevant impact parameters (such as electrode diameter, electrode shape, electrode material, and barrier material, etc.) of NTP reactor energy optimization are discussed. The work of this paper is of great significance for guiding the high-efficiency removal of CH4 and NOx for an NTP-CH4-SCR system. [ABSTRACT FROM AUTHOR]

Transformation of CO2 into value‐added chemicals remains a key challenge. Herein, nonthermal plasma (NTP)‐activated CO2‐H2O conversion over BaTiO3‐mixed NiO/CeO2 (Ni/Ce+) and Co3O4/CeO2 (Co/Ce+) catalysts is demonstrated. In a continuous‐flow dielectric barrier discharge reactor and under ambient conditions, optimum Co/Ce+ showed formation rates of CO and O2 of (43.6 ± 3.1) and (20.8 ± 0.7) μmol g−1h−1, respectively. CO2 conversion was found to be dependent on a combination of the basicity of the catalyst surface, CO2 flow rate, plasma input power, and relative humidity. Subsequently, kinetic analysis suggested that the activation energies over Ni/Ce+, Co/Ce+, and NiCo/Ce+ are 35.68, 15.61, and 25.88 kJ mol−1, respectively. By combining these findings, a plausible reaction mechanism that can facilitate understanding the trend of product formation is also provided. [ABSTRACT FROM AUTHOR]

Significance: The significance of ferroptosis in cancer therapeutics has now been unveiled. Specific ferroptosis inducers are expected as a promising strategy for cancer treatment, especially in cancers with epithelial mesenchymal transition and possibly in cancers with activated Hippo signaling pathways, both of which cause resistance to traditional chemotherapy but tend to show ferroptosis susceptibility. Recent Advances: Ferroptosis is a new form of regulated non-apoptotic cell death, which is characterized by iron-dependent lipid peroxidation, leading eventually to plasma membrane rupture. Its core mechanisms have been elucidated, consisting of a driving force as catalytic Fe(II)-dependent Fenton reaction and an incorporation of polyunsaturated fatty acids to membrane phospholipids via peroxisome-dependent and -independent pathways, and suppressing factors as prevention of lipid peroxidation with glutathione peroxidase 4 and direct membrane repair via coenzyme Q10 and ESCRT-III pathways. Critical Issues: Developments of ferroptosis inducers are in progress by nanotechnology-based drugs or by innovative engineering devices. Especially, low-temperature (non-thermal) plasma is a novel technology at the preclinical stage. The exposure can induce ferroptosis selectively in cancer cells rich in catalytic Fe(II). Future Directions: We also summarize and discuss the recently uncovered responsible molecular mechanisms in association with iron metabolism, ferroptosis and cancer therapeutics. Targeting ferroptosis in addition to the current therapeutic modalities would be important to cure advanced-stage cancer. Antioxid. Redox Signal. 39, 206–223. [ABSTRACT FROM AUTHOR]

Lower flow rates of precursor molecules are favorable for the synthesis of thin‐film materials using nonthermal plasma at a higher degree of dissociation and sufficiently high deposition rate. These deposition conditions can be used for both continuous wave (CW) and pulsed plasmas and result in higher consumption of precursor molecules, which is beneficial for industrial applications due to cost reduction. A wider range of power can be used to control the chemical and physical properties of thin‐film materials based on power‐dependent plasma chemistry. Hydrogenated amorphous silicon carbide films deposited in CW and pulsed plasma are used as an example. The different kinetics of film growth and the role of self‐bias voltage in both types of plasma are discussed. [ABSTRACT FROM AUTHOR]

This study investigated the effects of nonthermal Ar/O2 plasma on the osseointegration of titanium implants. Through 8 weeks' in vivo evaluation of implants inserted into femoral bones of male Sprague-Dawley rats, the new bone mineralization apposition rate (MAR) is increased by 1.87 and 2.14 times for implants of smooth machined (SM) and sand-blasted and acid-etched (SLA) after plasma treatment. The bone volume fraction (bone volume/total volume, BV/TV) and bone-implant contact (BIC) ratios are improved by 1.31, 1.26 times and 1.35, 1.15 times after 90 s plasma treatment. The improved hydrophilicity rather than implant surface morphology is believed to play a critical role for the osseointegration improvement. [ABSTRACT FROM AUTHOR]

Transformation of CO2 into value‐added chemicals remains a key challenge. Herein, nonthermal plasma (NTP)‐activated CO2‐H2O conversion over BaTiO3‐mixed NiO/CeO2 (Ni/Ce+) and Co3O4/CeO2 (Co/Ce+) catalysts is demonstrated. In a continuous‐flow dielectric barrier discharge reactor and under ambient conditions, optimum Co/Ce+ showed formation rates of CO and O2 of (43.6 ± 3.1) and (20.8 ± 0.7) μmol g−1h−1, respectively. CO2 conversion was found to be dependent on a combination of the basicity of the catalyst surface, CO2 flow rate, plasma input power, and relative humidity. Subsequently, kinetic analysis suggested that the activation energies over Ni/Ce+, Co/Ce+, and NiCo/Ce+ are 35.68, 15.61, and 25.88 kJ mol−1, respectively. By combining these findings, a plausible reaction mechanism that can facilitate understanding the trend of product formation is also provided. [ABSTRACT FROM AUTHOR]