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The aggressiveness and limited treatment options make triple‐negative breast cancer (TNBC) a challenging condition to treat. Immune checkpoint blockade therapy, explicitly targeting the programmed death‐ligand 1 (PD‐L1) pathway, is a promising therapeutic approach. However, the effectiveness of PD‐L1 inhibitors like atezolizumab depends on adequate PD‐L1 expression within cancer cells. To this end, this study used nonthermal plasma (NTP) to modulate PD‐L1 in TNBC cells. The current investigation revealed that NTP treatment leads to an upregulation of PD‐L1; this might increase the availability of PD‐L1 to PD‐L1 inhibitors. These findings suggest that shortly NTP could be used as an adjunctive treatment to immunotherapy in TNBC cells. [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]

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]

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]

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]

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]

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]

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]

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]

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]

Plasma‐treated liquid media containing amino acids have been shown to be effective as disinfectants and antitumor agents. The current study presents chemical analyses and bactericidal properties of mixtures formed by the treatment of phenylalanine and tyrosine in phosphate‐buffered saline in He/O2 plasma. A major process observed was the formation of amino acid mono‐ and di‐chloramines accompanied by the oxidation of the amino acid aromatic ring. The chemical activity of treated solutions lasted up to 90 min after plasma treatment. After being acidified to ~pH 3, the treated solutions exhibited a bactericidal effect against Escherichia coli. This effect was associated with the post‐discharge reactions of amino acid dichloramines and the formation of C‐1 nitrile as the final product. [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 power dependence of the plasma species in nonthermal tetravinylsilane plasmas used for thin‐film deposition is investigated by mass spectrometry. Mass spectra analysis reveals the dominant carbon‐ and silicon‐containing species responsible for film growth. The deposition rate determined by in situ spectroscopic ellipsometry correlates with the flux of these species chemisorbed on the film surface if distinct sticking coefficients are taken into account. Then, the carbon to silicon ratio in the deposited film strongly correlates with the C/Si flux ratio for the various power‐controlled plasmas. Similarly, the concentration of vinyl groups incorporated into the deposited film and the proportion of sp2 hybridization of the carbon network correlate with the fluxes of the respective plasma species. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) nanoparticles have excellent properties and varied possible applications. However, the synthesis of this material usually requires high temperatures due to its high melting point (2730°C). In this study, we report on a synthesis of highly spherical SiC nanocrystals (50–150 nm) using nonthermal plasma, a method not yet widely employed for the synthesis of SiC, but generally very suitable for high‐melting‐point materials. We perform the synthesis in a two‐stage reactor, where Si nanocrystals are synthesized in the first stage and these are used as growth seeds for SiC in the second stage. The Si nanocrystals remain inside the SiC nanoparticles after the synthesis. The produced SiC nanocrystals exhibit yellow‐orange naked‐eye‐visible photoluminescence. [ABSTRACT FROM AUTHOR]

Nonthermal plasma (NTP) can oxidize and decompose particulate matter (PM) of diesel engines at low temperatures (≤200°C), exhibiting good application prospects. PM samples were collected under different diesel engine loads and were oxidized using an NTP method. The volatile fraction (VF) mass fraction of the PM samples decreases under low engine loads (<70%) and increases under high engine loads (≥70%) after the NTP treatment. NTP can remove aldehyde groups in PM and weaken the volatilization of PM. A higher temperature is needed for the VF to reach its maximum volatilization rate after the NTP treatment. The relative content of the small molecules is significantly higher after the NTP treatment. [ABSTRACT FROM AUTHOR]

Compared with many chemotherapy and radiotherapy modalities, selective killing of cancer cells is a pivotal feature of cold atmospheric plasma (CAP). Understanding its underlying mechanism will build the foundation of CAP‐based cancer treatment. Additionally, we provided forward‐looking thinking to extend the definition of selectivity from conventional cases involving a single‐cell line to a coculture case. Finally, the newly established physically based treatment strategy provides unprecedented visions to realize selectivity beyond the previously established concepts based on reactive species and direct killing effect. [ABSTRACT FROM AUTHOR]

Ion mobility spectrometry was used to monitor the degradation of phthalate vapors by corona discharge. Three different phthalates (dimethyl [DMP], diethyl [DEP], and dipropyl [DPP]) were examined in a corona discharge reactor (wire‐to‐cylinder geometry) at direct current positive polarity in ambient air. The relative removal efficiencies up to 96% and energetical degradation efficiencies of 229.27, 216.12, and 198.84 kJ mg−1 were achieved for DMP, DEP, and DPP, respectively. Byproducts such as methanol, ethanol, and 1‐ and 2‐propanol at extremely low densities were also detected. The identified degradation processes involved two steps: (i) An electron‐impact dissociation of phthalates into alkoxyl radicals and (ii) reactions of alkoxy radicals with water molecules to form alcohols. [ABSTRACT FROM AUTHOR]

A rotating gliding arc is proposed as a promising alternative to enable direct nitrogen fixation from ubiquitous air under mild conditions. The effect of different process parameters on NOx generation and energy consumption has been investigated through a combination of experiments and artificial neural network (ANN) modeling. The optical emission spectroscopic diagnostics together with electrical diagnostics and high‐speed photography has been used to understand the variation of the discharge characteristics. The lowest energy consumption of NOx production (4.2 MJ/mol) is achieved at a gas flow rate of 12 L/min and an O2 concentration of 20 vol%. The simulation results from the ANN model show a good agreement with the experimental data and the model enables us to evaluate the relative importance of the process parameters to the reaction performance. [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]

This proof‐of‐principle study explored the possibility to form nitrogen‐containing organic products via exposure of liquid toluene to a flow of molecular nitrogen, at room temperature and atmospheric pressure, activated by dielectric barrier discharges. N‐containing organic compounds indeed formed under these conditions, including benzonitrile, a high‐value chemical that is industrially synthesized from toluene under demanding conditions. Toluene‐derived higher hydrocarbons, as well as oxygen‐containing derivatives, were also detected, the latter due to efficient reactions of residual oxygen in the system. A mechanistic description of the observed chemistry is provided, together with guidelines for increasing the selectivity for C–N forming reactions and the development of this approach into a novel synthetic approach for high‐value organic N‐containing chemicals. [ABSTRACT FROM AUTHOR]

The present study combines nonthermal plasma (NTP) and thermal catalysis to exploit the synergism for direct conversion of CO2 to CH3OH using H2. Series of catalyst, that is, CuO/QW, NiO/QW, Fe2O3/QW, NiO/Fe2O3/QW, CuO/Fe2O3/QW have been tested for CO2 conversion and CH3OH selectivity. And it was observed that 5 wt% CuO/Fe2O3/QW exhibited better CO2 conversion and CH3OH selectivity as compared to other catalysts. With 5 wt% CuO/Fe2O3/QW, at 200°C and 2‐W NTP input power (100 ml/min feed flow and 1:3 ratio of CO2 and H2) about 16.7% CO2 conversion and 32.7% CH3OH selectivity have been reached. Indeed, the highest of 9.32 mmol h−1 gcat−1 of CH3OH space‐time yield is obtained over CuO/Fe2O3/QW, which is about two times higher than the reported value in the literature (4.41 mmol h−1 gcat−1 of CH3OH using Cu/ZnO/Al2O3, 30°C, feed flow 40 ml/min, and 30‐W input power). [ABSTRACT FROM AUTHOR]

Charge particles can increase the biocidal efficacy of nonthermal plasmas in indirect treatments. The aim of this study is to increase the amount of free charges produced and delivered by a surface dielectric barrier discharge fluid‐dynamics actuator. Different linear actuators and supplying conditions have been considered. Actuators were utilized to produce an ionic wind impinging an insulating target surface. Charged particles' distribution over the target was measured with and without a metallic mesh between the actuator and target itself. Linear actuators have proven to be more effective in charge delivery with respect to an annular one previously studied by our research team. A two‐dimensional electrostatic finite‐element analysis has been carried out to get a better insight into this physical behavior. [ABSTRACT FROM AUTHOR]

In this study, a thin film composed of inorganic SiOx is deposited on the copper surface by atmospheric pressure plasma‐enhanced chemical vapor deposition. A pool boiling experiment is performed and the influence of the coating on pool boiling performance is examined. Morphology, composition, and wettability of the thin films are assessed using a scanning electron microscope, energy‐dispersive X‐ray spectrometer, and contact angle measurements. In addition to the enhancement of pool boiling thermal characteristics, especially a 103% increase in heat transfer coefficient, it is observed that the plasma‐deposited thin film on the copper surface is stable after the four boiling/cooling cycles. Finally, the underlying mechanism behind the improvements achieved by use of coated surface is studied. [ABSTRACT FROM AUTHOR]

Plasma agriculture details the role of nonthermal plasma in the development of plants from seeds to crops. Several publications reported enhanced plant growth, improved stress tolerance, and antimicrobial effects of plasma treatment and plasma‐treated water. In this review, we present an overview of the recent plasma agriculture literature and put it in the context of the plant needs and the effects on the plant ecosystem. We will discuss key developmental stages of plants and their needs, the different growth environments from hydroponics to soilless and soil substrates, and the plant microbiome. This review provides the context to design plasma‐based fertilization strategies to address the needs of plants and their ecosystem. [ABSTRACT FROM AUTHOR]

The effects of post‐plasma exposure to deionized water treated by argon–water plasma and to direct plasma treatment of bacteria in a liquid solution of a strain of Escherichia coli, which was independently evolved to resist the bactericidal effects of hydrogen peroxide, were determined. The hydrogen peroxide resistant phenotype of the evolved strain was proportional to the initial cell density. The catalase activity was significantly elevated in the evolved strain as compared with the wild‐type strain, and the evolved strain resisted the bactericidal effects of plasma‐treated water (post‐plasma exposure) as compared with the wild‐type strain. The evolved strain remained viable after flowing through the plasma reactor and lysed less when exposed to (nonplasma control) hydrogen peroxide solutions as compared with the wild‐type cells. [ABSTRACT FROM AUTHOR]

This study solves the problem of the invasivity of laser‐induced fluorescence (LIF) measurements caused by photodissociation. It is shown with the example of OH LIF that the excess signal caused by laser‐induced photodissociation can be distinguished from the true LIF signal of the naturally presented species by its different dependence on the energy of laser pulses. This fact can be further used for the detection of photodissociable species not accessible by the standard LIF. This method is applied to OH radicals in atmospheric‐pressure multihollow dielectric barrier discharge plasma ignited in a number of holes. OH radicals are concentrated at the effluents of these holes, but they are able to spread to a distance of 5 mm, meaning that the discharge is suitable for the treatment of distant and rough surfaces. [ABSTRACT FROM AUTHOR]

Most studies regarding plasma biomedicine applications mainly focus on the oxidative and/or nitrative stress on bacteria, cancer cells, and other treatment objects. In this study, we evaluate the protective effect of appropriate atmospheric pressure plasma jet (APPJ) treatments on oxygen and glucose deprivation (OGD)‐induced neural cell apoptosis, which is a major pathological process during ischemic stroke, based on the physiological functions of NO. Results show that APPJ treatment reduces the OGD‐induced apoptosis by weakening typical OGD injury consequences including loss of mitochondrial membrane potential, the release of cytochrome c from the mitochondria into the cytoplasm, lower antiapoptotic Bcl‐2 expression, and upregulating the proapoptotic protein Bax. Furthermore, APPJ increased intracellular NO production, which is closely related to the cytoprotective effect of APPJ. [ABSTRACT FROM AUTHOR]

Plasma‐activated water mist (PAWM) is obtained by the ignition of plasma within an air–vapor mixture. PAWM demonstrates significant antibacterial properties, decreasing loads of foodborne pathogens by a factor of 35.5 for Listeria monocytogenes, 166 for Salmonella Typhimurium, and 266 for Escherichia coli O157:H7 within 15 s. Bacterial biofilms have a similar species‐dependant susceptibility. Biofilms of L. monocytogenes, Salmonella Typhimurium, and E. coli O157:H7 are destroyed by 44%, 77%, and 71%, respectively, after being treated for 2 min. Obtained results suggest importance of short‐lived radicals, because PAWM condensate is not bactericidal. A new model of PAW generation as a cyclic process of oxidation reactive nitrogen species by reactive oxygen species, which occurs during effective bidirectional mass transfer between heavily humid air and water mist in plasma discharge, is presented. [ABSTRACT FROM AUTHOR]

Vaccination has been one of the most effective health intervention mechanisms to reduce morbidity and mortality associated with infectious diseases. Vaccines stimulate the body's protective immune responses through controlled exposure to modified versions of pathogens that establish immunological memory. However, only a few diseases have effective vaccines. The biological effects of nonthermal plasma on cells suggest that plasma could play an important role in improving efficacy of existing vaccines and overcoming some of the limitations and challenges with current vaccination strategies. This review summarizes the opportunities for nonthermal plasma for immunization and therapeutic purposes. [ABSTRACT FROM AUTHOR]

The penetration of reactive oxygen and nitrogen species (RONS) across the stratum corneum (SC) is a necessary and crucial process in many skin‐related plasma medical applications. To gain more insights into this penetration behavior, we combined experimental measurements of the permeability of dry and moist SC layers with computer simulations of model lipid membranes. We measured the permeation of relatively stable molecules, which are typically generated by plasma, namely H2O2, NO3−, and NO2−. Furthermore, we calculated the permeation free energy profiles of the major plasma‐generated RONS and their derivatives (i.e., H2O2, OH, HO2, O2, O3, NO, NO2, N2O4, HNO2, HNO3, NO2−, and NO3−) across native and oxidized SC lipid bilayers, to understand the mechanisms of RONS permeation across the SC. Our results indicate that hydrophobic RONS (i.e., NO, NO2, O2, O3, and N2O4) can translocate more easily across the SC lipid bilayer than hydrophilic RONS (i.e., H2O2, OH, HO2, HNO2, and HNO3) and ions (i.e., NO2− and NO3−) that experience much higher permeation barriers. The permeability of RONS through the SC skin lipids is enhanced when the skin is moist and the lipids are oxidized. These findings may help to understand the underlying mechanisms of plasma interaction with a biomaterial and to optimize the environmental parameters in practice in plasma medical applications. [ABSTRACT FROM AUTHOR]

To disclose water roles in plasma reforming of methanol for hydrogen production, gliding arc discharge characteristics, optical emission spectra, and reaction behavior are investigated over a water concentration range of 0–95 mol%. It can be concluded that the varied reaction behavior with water concentration derives from three water roles as a homogeneous catalyst, CO oxidant, and side‐product. The former two roles of water are beneficial for hydrogen production. The side‐product role of water, accompanied by hydrocarbons formation, which is disadvantageous to hydrogen production and can be almost fully inhibited by the homogeneous catalysis of water at above 33 mol% H2O. As an oxidant, water conversion is controlled by the thermodynamic equilibrium at the gas temperature of arc. [ABSTRACT FROM AUTHOR]

Solid structures of different shapes, hydrogen chloride, and a small number of liquid products are formed from chloromethanes (CH2Cl2 and CHCl3) and binary systems with triphenylphosphine (CH2Cl2 + PPh3, CHCl3 + PPh3, and CCl4 + PPh3) under the action of a liquid‐phase low‐voltage discharge (60‐V DC). It is observed that triphenylphosphine additives sharply increase the reactivity of CCl4. Besides, a quantum chemical simulation of chloromethane transformation mechanism in the binary systems with triphenylphosphine is conducted, together with the likely mechanism of chloromethane conversion into active particles under the action of a liquid‐phase low‐voltage pulsed discharge. [ABSTRACT FROM AUTHOR]

Integrating oxide coatings with narrow‐gap hybrid discharge (HD) can modulate ozone (O3) synthesis. O3 concentration (CO3) and energy yield (η) for HD can be enhanced by single‐valent oxides, whereas they are reduced by multivalent oxides. The discharge and oxide characterizations suggest that surface catalytic reactions play a crucial role in the synthesis of O3: single‐valent oxide coatings facilitate O3 production by offering abundant catalytic sites for surface catalytic reactions; surface catalytic reactions on multivalent oxide coatings suppress O3 production because of the dominating O3 decomposition over highly active sites of oxygen vacancies. This study is inspirational for designing and fabricating high‐efficiency O3 generators. [ABSTRACT FROM AUTHOR]

III–V semiconductor nanocrystals are an important class of optoelectronic materials. However, the gas‐phase synthesis of these materials, especially of the stibnides, has been left relatively unexplored. In this study, we demonstrate the synthesis of free‐standing GaSb nanocrystals for the first time, using a novel gas‐phase process. We show that when elemental aerosols are used as precursors for Ga and Sb, the elements mix at the nanometer length scale as the aerosols pass through a nonequilibrium plasma reactor. At sufficiently high plasma power, the mixing produces free‐standing GaSb nanocrystals, with a small amount of excess Ga segregated at the periphery of the particles. The reaction is initiated by vaporization of elemental aerosols in the plasma despite the low‐background temperature. Ion bombardment determines the extent of vaporization of Ga and Sb and thereby controls the ensemble stoichiometry and reaction rates. [ABSTRACT FROM AUTHOR]

We propose a pretreatment method for monosilane (SiH4) gas by high‐density plasma toward the relatively low‐temperature formation (≤600°C) of a crystalline Si film by thermal chemical vapor deposition (TCVD). SiH4 reaction behaviors with the plasma are investigated by using gas‐phase Fourier‐transform infrared spectroscopy. The dependence of the Si2H6 formation characteristics on total gas flow rate and input microwave power is examined. Si2H6 gas yields with the plasma treatment for SiH4 gas increased with decreasing input microwave power and increased with increasing total gas flow rate. Si films are prepared by TCVD using the plasma‐treated SiH4 gas. As a result, the pretreatment for SiH4 gas by high‐density plasma affects not only the deposition rate but also the crystallinity of the obtained Si film. The mechanism by which Si film formation is improved by plasma treatment is discussed. [ABSTRACT FROM AUTHOR]

Fungal infections induced by Candida albicans have increased worldwide due to emerging resistance to antifungal agents, which is largely caused by biofilm formation. Thus, a new and effective antimicrobial strategy is urgently required in treatment of C. albicans biofilm‐associated infections. In this study, the inactivation effects of cold plasma treatment for C. albicans biofilm are assessed in vitro and in vivo. In vitro studies indicate that C. albicans in suspension and the C. albicans biofilm are inactivated significantly by plasma treatment. In vivo studies indicate that plasma treatment achieves the best antifungal effect with an optimal dose (4 min in this case), as excessive plasma treatment damages the normal tissues and thus induces aggravation of infection compared to the 4‐min group. [ABSTRACT FROM AUTHOR]

Collagen coating of polystyrene (PS) labware involves a multistep process with high costs and complexity. Nonthermal plasma processes have recently been found to deposit coagulated and biologically functional protein layers in a single process step. A series of investigations were, therefore, conducted to compare plasma‐deposited collagen to an equivalent commercially coated product. Chemical and microscopic analysis suggests that the plasma‐deposited collagen retains the surface morphology and functional chemistry of the traditional collagen coating. Cell‐culture studies using two separate cell lines confirmed that the plasma‐deposited materials replicated the cell viability, proliferation and activity of the traditional collagen surfaces and outperformed uncoated PS plates. The implications of this for the protein coating of plastic labware surfaces are discussed. [ABSTRACT FROM AUTHOR]

The objective of this study is to determine whether there is a pathway different from the natural blood coagulation process involved in the plasma-induced activation of platelets and coagulation factors. Plasma treatment of bleeding wounds generated glomerular structures, which could be detected in high-magnification scanning electron microscopy images, and plasma flares produced aggregation on the surface of solutions containing bovine serum albumin, ovalbumin (OVA), or similar protein material. Ultramicroscopic analysis of the plasma-generated aggregation of OVA indicated a possiblemechanism to explain the particle formation and fusion as a monotonous solid appearance. This study suggests that plasma coagulation involves aggregations of materials in blood in addition to the activation of platelets and coagulation factors by plasma treatment. [ABSTRACT FROM AUTHOR]

Cold Atmospheric plasma has been studied extensively over the last decade with applications ranging from bacterial decontamination to wound healing. Although numerous designs of plasma applicators have been developed for direct exposure, prolonged exposure required for decontamination of tissues and skin may be detrimental to mammalian cells. In this study, we evaluate the effect of plasma generated by surface dielectric barrier discharge (SDBD) on mammalian cells, including HUVEC, Neuroblastoma, and HepG2. SDBD actuator induces flow and can transport plasma-generated species to the surface being treated. Cell morphology, viability, and functionality are evaluated by incubating cells after exposure to SDBD for 1, 4 and 8 min. All cell types demonstrate retention of viability without any necrotic response, although, with an increase in the number of injured cells, with increase in exposure time. Cell-specific responses are observed with HUVEC demonstrating highest resilience as compared to neuroblastoma and HepG2 (lowest). Migration assay using HUVEC shows no effect on viability and functionality with 4 min exposure. The 8 min tests demonstrated no additional change in morphology, so we conclude that SDBD does not affect the cell morphology at longer exposure durations as compared to other plasma sources and can be applied safely in medical applications. [ABSTRACT FROM AUTHOR]

By applying dielectric-barrier discharge nonthermal plasma technique, we have treated fluids and generated antimicrobial solutions, tested for properties such as changes in pH, temperature, delay time, holding time, fluid-aging, and detection and comparison of acid and hydrogen peroxide. All plasma-treated solutions showed strong biocidal activity, and among them, NAC solution was the most powerful, inactivated biofilms of tested microorganisms in 15 min of holding time. During accelerated aging experiments, plasma-treated NAC solution exhibited the equivalent of two years of shelf. These results indicate that it retained its antimicrobial properties for an extended period against a wide range of multidrug-resistant pathogens, making it an excellent candidate for further testing in vivo. [ABSTRACT FROM AUTHOR]

Poly(3,4‐ethylenedioxythiophene) or PEDOT is a promising conductive polymer, which generally uses anionic polystyrene sulfonate (PSS) as the template to become water soluble. Besides the chemical and enzymatic approaches, we are presenting a novel method by employing nonthermal plasma‐activated hydrogen peroxide (PAH) to promote the synthesis of water‐soluble PEDOT(PSS), which is a more environment‐friendly technology. The reaction did not utilize any other chemical solvents, except for a monomer, template as well as hydrogen peroxide, and was initiated in a neutral aqueous solution. We have found that a heating procedure under 60°C was necessary for the effective synthesis of PEDOT(PSS). The final product was further characterized by UV–Vis spectrum, Fourier‐transform infrared spectroscopy, and conductivity measurements. [ABSTRACT FROM AUTHOR]

In this paper, extensive studies are conducted as key to overcoming several challenging limitations in applying fluorine‐based reactive plasma jet machining (PJM) to surface machining of N‐BK7®, particularly regarding the manufacture of freeform optical elements. The chemical composition and lateral distributions of the residual layer are evaluated by X‐ray photoelectron spectroscopy and scanning electron microscopy/energy‐dispersive X‐ray spectroscopy analysis aiming at clarifying the exact chemical kinetics between plasma generated active particles and the N‐BK7 surface atoms. Subsequently, a model is developed by performing static etchings to consider the time‐varying nonlinearity of the material removal rate and estimate the local etching rate function. Finally, the derived model is extended into the dynamic machining process, and the outcomes are compared with the experimental results. [ABSTRACT FROM AUTHOR]

A nonthermal plasma produced at atmospheric pressure in the gas resulted from the surrounding liquid is named solution plasma (SP). A quantitative and comparative spectrochemical analysis of the plasma gas and solution in benzene, pyridine, and aniline is performed. The number densities of dicarbon and cyano radicals and hydrogen molecule from the plasma gas are measured using a cheap, straightforward, and home‐made optical set‐up. By simply modifying the optical set‐up, the molar concentration of newly formed chemical compounds is in situ obtained in the solution. The thermodynamic properties of aromatic molecules determine the electrical breakdown and the species number densities in the plasma gas. The production rate and atomic composition of carbon material are correlated with the radicals from plasma gas. [ABSTRACT FROM AUTHOR]

Climate change, environmental pollution control, and resource utilization efficiency, as well as food security, sustainable agriculture, and water supply are among the main challenges facing society today. Expertise across different academic fields, technologies, and disciplines is needed to generate new ideas to meet these challenges. This "white paper" aims to provide a written summary by describing the main aspects and possibilities of the technology. It shows that plasma science and technology can make significant contributions to address the mentioned issues. The paper also addresses to people in the scientific community (inside and outside plasma science) to give inspiration for further work in these fields. Climate change, environmental pollution control, and resource utilization efficiency, as well as food security, sustainable agriculture, and water supply are among the main challenges facing society today. Expertise across different academic fields, technologies, and disciplines is needed to generate new ideas to meet these challenges. This "white paper" aims to provide a written summary by describing the main aspects and possibilities of the technology. It shows that plasma science and technology can make significant contributions to address the mentioned issues. The paper also addresses to people in the scientific community (inside and outside plasma science) to give inspiration for further work in these fields. [ABSTRACT FROM AUTHOR]