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The interaction of an ambient air plasma with a water surface in a pin-water electrode configuration is presented in a polydiagnostic study. A discharge was generated by applying different high-voltage (HV) waveforms to a metallic pin electrode, positioned 2 mm above the water surface of a Petri dish filled with demineralized water. For pulsed discharge operation, a clear distinction is observed between a dielectric barrier discharge regime featuring a transient discharge at the rising as well as at the falling slope of the HV pulse, while a steady discharge is present in the gap during the complete HV pulse for the electrolysis regime. The occurrence of those two regimes is coupled to the increasing conductivity of the water over time, which additionally results in a quick rise of the dissipated discharge power and an increase of the gas temperature. The AC driven discharges exhibit only the electrolysis regime and do not significantly evolve over the treatment time. The resulting water conductivity was found to be a function of the total dissipated energy, irrespective of the discharge driving mode. Additionally, the resulting water conductivity shows a strong correlation with the total transferred charge in the gas phase. The total dissipated energy can potentially be used as a global measure to compare different experiments involving plasma-water interaction across different setups in different research groups.

A 25L working volume non-thermal plasma-based treatment reactor was trialled to destroy Per- and polyfluoroalkyl substances (PFAS) utilising argon bubbles to transport PFAS to the surface to be destroyed with plasma interaction at the argon-liquid interface. The breakdown rate of PFAS and the system's overall energy efficiency could be improved while minimising gas usage by utilising small bubbles (0.6–0.7 mm d32) to maximise the transport of PFAS to the plasma discharge for destruction. Vertically scaling the treatment reactor dimensions increases the overall liquid height and dwell time for bubbles to contact and transport PFAS molecules to the surface. The removal rate of perfluorooctane sulfonate (PFOS) correlated with the total surface area of the gas. Significant concentration gradients of PFOS could be observed when sampling from different liquid heights within the 25 L reactor. A one-dimensional model of mass transfer to the surface of rising bubbles was developed and gave good predictions of the overall rates of PFOS breakdown with modelled time constants of 0.14–0.18 min−1 versus 0.16+/−0.01 min−1 for the fine bubble diffuser, and 0.048–0.053 min−1 versus 0.06 min−1 for the medium bubble diffuser. The time constant compared favourably with similar experiments at the 2 L scale of 0.11 min−1.

The objective of this research is to describe the impact of different advanced oxidation processes used for the removal of sulfamethoxazole on wastewater quality. Ozone, UV, a combination of ozone and UV, and plasma discharge were employed. Concentrations of sulfamethoxazole were analysed by LC-MS/MS. Chemical and microbiological analyses and ecotoxicological tests were conducted to investigate the quality of treated wastewater. The results of this study show that the most effective technique for the removal of sulfamethoxazole is O3, followed by plasma discharge, O3 + UV and, finally, UV. A significant effect of tested advanced oxidation processes on the chemical composition of wastewater was not observed; however, the number of microorganisms was reduced. In the case of ecotoxicological tests with Lemna minor and crustacean Daphnia magna, a significant negative effect was only observed when plasma was applied.

The objective of this research is to describe the impact of different advanced oxidation processes used for the removal of sulfamethoxazole on wastewater quality. Ozone, UV, a combination of ozone and UV, and plasma discharge were employed. Concentrations of sulfamethoxazole were analysed by LC-MS/MS. Chemical and microbiological analyses and ecotoxicological tests were conducted to investigate the quality of treated wastewater. The results of this study show that the most effective technique for the removal of sulfamethoxazole is O3, followed by plasma discharge, O3 + UV and, finally, UV. A significant effect of tested advanced oxidation processes on the chemical composition of wastewater was not observed; however, the number of microorganisms was reduced. In the case of ecotoxicological tests with Lemna minor and crustacean Daphnia magna, a significant negative effect was only observed when plasma was applied.

The objective of this research is to describe the impact of different advanced oxidation processes used for the removal of sulfamethoxazole on wastewater quality. Ozone, UV, a combination of ozone and UV, and plasma discharge were employed. Concentrations of sulfamethoxazole were analysed by LC-MS/MS. Chemical and microbiological analyses and ecotoxicological tests were conducted to investigate the quality of treated wastewater. The results of this study show that the most effective technique for the removal of sulfamethoxazole is O3, followed by plasma discharge, O3 + UV and, finally, UV. A significant effect of tested advanced oxidation processes on the chemical composition of wastewater was not observed; however, the number of microorganisms was reduced. In the case of ecotoxicological tests with Lemna minor and crustacean Daphnia magna, a significant negative effect was only observed when plasma was applied.

The depletion of fossil fuel reserves and severe environmental damage, resulting in climate change and global warming lead to a necessary shift to alternative renewable resources. Lignocellulose is a valuable feedstock for biorefineries, but its conversion is hindered by the limitations of conventional pretreatments lacking selectivity. This step should also be cost-effective and sustainable. In this paper, combined advanced oxidation techniques were applied for the treatment of corn stalks as a pretreatment for enzymatic hydrolysis. Their effect on delignification and cellulose digestibility was monitored. The combined non-thermal plasma/Fenton treatment appears to be suitable for breaking the complex lignocellulose structure, with a lignin content decrease of 39%. This treatment enhanced carbohydrate hydrolysis, resulting in 2.25 times increase in hexose yield, compared to the untreated sample. Long-term plasma treatment positively affected the textural properties, total porosity, and pore size diameter, of lignocellulose biomass. It enables the creation of materials with a stable system of pores and channels, for the unhindered diffusion of large organic molecules such as enzymes. Additionally, a combination of plasma treatment with Fenton reaction increased selectivity towards lignin degradation in comparison to independently applied Fenton treatment. This could be a significant advantage for a bottleneck in the current valorization of biomass.

The objective of this research is to describe the impact of different advanced oxidation processes used for the removal of sulfamethoxazole on wastewater quality. Ozone, UV, a combination of ozone and UV, and plasma discharge were employed. Concentrations of sulfamethoxazole were analysed by LC-MS/MS. Chemical and microbiological analyses and ecotoxicological tests were conducted to investigate the quality of treated wastewater. The results of this study show that the most effective technique for the removal of sulfamethoxazole is O3, followed by plasma discharge, O3 + UV and, finally, UV. A significant effect of tested advanced oxidation processes on the chemical composition of wastewater was not observed; however, the number of microorganisms was reduced. In the case of ecotoxicological tests with Lemna minor and crustacean Daphnia magna, a significant negative effect was only observed when plasma was applied.

The objective of this research is to describe the impact of different advanced oxidation processes used for the removal of sulfamethoxazole on wastewater quality. Ozone, UV, a combination of ozone and UV, and plasma discharge were employed. Concentrations of sulfamethoxazole were analysed by LC-MS/MS. Chemical and microbiological analyses and ecotoxicological tests were conducted to investigate the quality of treated wastewater. The results of this study show that the most effective technique for the removal of sulfamethoxazole is O3, followed by plasma discharge, O3 + UV and, finally, UV. A significant effect of tested advanced oxidation processes on the chemical composition of wastewater was not observed; however, the number of microorganisms was reduced. In the case of ecotoxicological tests with Lemna minor and crustacean Daphnia magna, a significant negative effect was only observed when plasma was applied.

The objective of this research is to describe the impact of different advanced oxidation processes used for the removal of sulfamethoxazole on wastewater quality. Ozone, UV, a combination of ozone and UV, and plasma discharge were employed. Concentrations of sulfamethoxazole were analysed by LC-MS/MS. Chemical and microbiological analyses and ecotoxicological tests were conducted to investigate the quality of treated wastewater. The results of this study show that the most effective technique for the removal of sulfamethoxazole is O3, followed by plasma discharge, O3 + UV and, finally, UV. A significant effect of tested advanced oxidation processes on the chemical composition of wastewater was not observed; however, the number of microorganisms was reduced. In the case of ecotoxicological tests with Lemna minor and crustacean Daphnia magna, a significant negative effect was only observed when plasma was applied.

The objective of this research is to describe the impact of different advanced oxidation processes used for the removal of sulfamethoxazole on wastewater quality. Ozone, UV, a combination of ozone and UV, and plasma discharge were employed. Concentrations of sulfamethoxazole were analysed by LC-MS/MS. Chemical and microbiological analyses and ecotoxicological tests were conducted to investigate the quality of treated wastewater. The results of this study show that the most effective technique for the removal of sulfamethoxazole is O3, followed by plasma discharge, O3 + UV and, finally, UV. A significant effect of tested advanced oxidation processes on the chemical composition of wastewater was not observed; however, the number of microorganisms was reduced. In the case of ecotoxicological tests with Lemna minor and crustacean Daphnia magna, a significant negative effect was only observed when plasma was applied.

CAP is a form of plasma with a temperature below 104°F at the application site. There are a variety of techniques for producing CAP, including Atmospheric Pressure Plasma Jet, Dielectric Barrier Discharge, and plasma needle and pencil. Multiple gases can produce CAP, including Helium, Heliox, Nitrogen, Argon, and air. Due to CAP's ability to deactivate organisms, cause cell separation, and kill cancer cells, researchers are interested in identifying dental and oncological applications for the compound. CAP is an ionized gas at 25 Co; it produces ROS and RNS due to several factors such as U.V., ray, heat, and power electric effects. Plasma is a matter at (fourth state) formed at low pressure or high temperature. Often, it is described as an ionized gas produced by the polyatomic fragmentation or the subtraction of electrons from monatomic gas shells. CAP has an antitumor effect. The current study aims to shed light on CAP technology, its definition, types, general applications, and their applications in treating human cancer. CAP was effective in treating cancer and eliminating tumor cells. CAP may have a place in the therapy of cancer. CAP used for cancer therapy has many advantages as a therapeutic method due to its effects of high selectivity, non-toxicity, combination potential, and adaptability. CAP eradicates cancer cells and uses this technique as a clinical therapeutic option that is effective and safe.

CAP is a form of plasma with a temperature below 104°F at the application site. There are a variety of techniques for producing CAP, including Atmospheric Pressure Plasma Jet, Dielectric Barrier Discharge, and plasma needle and pencil. Multiple gases can produce CAP, including Helium, Heliox, Nitrogen, Argon, and air. Due to CAP's ability to deactivate organisms, cause cell separation, and kill cancer cells, researchers are interested in identifying dental and oncological applications for the compound. CAP is an ionized gas at 25 Co; it produces ROS and RNS due to several factors such as U.V., ray, heat, and power electric effects. Plasma is a matter at (fourth state) formed at low pressure or high temperature. Often, it is described as an ionized gas produced by the polyatomic fragmentation or the subtraction of electrons from monatomic gas shells. CAP has an antitumor effect. The current study aims to shed light on CAP technology, its definition, types, general applications, and their applications in treating human cancer. CAP was effective in treating cancer and eliminating tumor cells. CAP may have a place in the therapy of cancer. CAP used for cancer therapy has many advantages as a therapeutic method due to its effects of high selectivity, non-toxicity, combination potential, and adaptability. CAP eradicates cancer cells and uses this technique as a clinical therapeutic option that is effective and safe.

Non-thermal plasmas are used in various applications to inactivate biological agents or biomolecules. A complex cocktail of reactive species, (vacuum) UV radiation and in some cases exposure to an electric field together cause the detrimental effects. In contrast to this disruptive property of technical plasmas, we have shown previously that it is possible to use non-thermal plasma-generated species such as H2O2 as cosubstrates in biocatalytic reactions. One of the main limitations in plasma-driven biocatalysis is the relatively short enzyme lifetime under plasma-operating conditions. This challenge could be overcome by immobilizing the enzymes on inert carrier materials. Here, we tested whether immobilization is suited to protect proteins from inactivation by plasma. To this end, using a dielectric barrier discharge device (PlasmaDerm), plasma stability was tested for five enzymes immobilized on ten different carrier materials. A comparative analysis of the treatment times needed to reduce enzyme activity of immobilized and free enzyme by 30% showed a maximum increase by a factor of 44. Covalent immobilization on a partly hydrophobic carrier surface proved most effective. We conclude from the study, that immobilization universally protects enzymes under plasma-operating conditions, paving the way for new emerging applications., BT/Biocatalysis

Lactic acid bacteria have an important role in food production, as probiotics and producers of lactic acid. Due to the generation of oxygen and nitrogen-based reactive species and UV radiation, non-thermal plasma (NTP) was found to be effective in microbial inactivation and food processing. In this study, we investigated the effect of atmospheric NTP on Lacticaseibacillus paracasei NRRL B-4564 survival, membrane alternations, and the response of treated cells to acidic stress. Cell suspensions in water were subjected to different treatment time intervals using a custom-made plasma needle. Argon was used as a feed gas, with a flow of 0.5 slm, while the distance between the needle tip and suspension surface was 1.5 cm. Immediately after the treatment, the viable cell number was estimated by the pour plate method, while cell membrane alternations were studied by analyzing zeta potential and membrane permeability (Crystal Violet assay). To ascertain if sub-lethal NTP stress could influence L. paracasei survival in an acidic environment, NTP-treated cells were challenged by pH 2.5 for 3h. The results demonstrate that the negative surface potential of the bacterial membrane (-29.83±1.49 mV for untreated) was gradually shifted towards neutrality (-7.59±0.54 mV after 180 s) with prolonged treatment time. Increasing cell exposure to NTP resulted in higher membrane permeability, which was correlated with viable cell reduction. The cells exposed to shorter treatment time (30 and 60 s) kept viability and showed better survival in low pH compared to untreated cells, suggesting the application of NTP in probiotic food processing.

The use of antibiotics constantly increases which has a notable negative impact on water bodies. Ciprofloxacin (CIP) is widely applied antibiotic in both human and veterinary medicine, as well as in a livestock breeding. Due to its extensive use, CIP has been found in wastewater effluents in a wide concentration range from ng to mg dm^(–3). An extremely high concentration of up to 50 mg dm^(–3) has been found near drug manufacturing plants [1]. Since CIP, as well as many other pharmaceuticals, cannot be efficiently removed from wastewater streams by conventional wastewater treatments, it is of a great importance to find an acceptable method for their removal. This study reports the use of natural calcium-rich clinoptilolite (CLI) for the adsorption of CIP and regeneration of the spent adsorbent (CLI-CIP) by non-thermal atmospheric pressure plasma (NTP). The results show that the CLI possesses a high adsorption efficiency in removal of CIP at 283, 288 and 293 K in a slightly acidic medium (pH= 5) for the initial concentrations from 15 to 75 mg dm^(–3). The CIP adsorption by CLI follows the Lagergren’s pseudo-second-order kinetics and it can be described well by the Langmuir isotherm model. For all studied temperatures and initial concentrations more than 85% of the CIP is removed within the first 10 minutes. The results also indicate that the CIP adsorption mechanism includes two phenomena: 1) electrostatic interactions between negatively charged aluminosilicate lattice and cationic form of CIP species and 2) ion-exchange reaction. The use of NTP for the regeneration of CLI-CIP was based on the assumption that NTP generates highly reactive species which can induce a cleavage of the bonds formed between active sites on the CLI surface and CIP, and also induce the CIP decomposition. The NTP treatment was performed for a short time, with a low energy consumption, and without using the additional chemicals. All these make the procedure acceptable not only from economical

The depletion of fossil fuel reserves and severe environmental damage, resulting in climate change and global warming lead to a necessary shift to alternative renewable resources. Lignocellulose is a valuable feedstock for biorefineries, but its conversion is hindered by the limitations of conventional pretreatments lacking selectivity. This step should also be cost-effective and sustainable. In this paper, combined advanced oxidation techniques were applied for the treatment of corn stalks as a pretreatment for enzymatic hydrolysis. Their effect on delignification and cellulose digestibility was monitored. The combined non-thermal plasma/Fenton treatment appears to be suitable for breaking the complex lignocellulose structure, with a lignin content decrease of 39%. This treatment enhanced carbohydrate hydrolysis, resulting in 2.25 times increase in hexose yield, compared to the untreated sample. Long-term plasma treatment positively affected the textural properties, total porosity, and pore size diameter, of lignocellulose biomass. It enables the creation of materials with a stable system of pores and channels, for the unhindered diffusion of large organic molecules such as enzymes. Additionally, a combination of plasma treatment with Fenton reaction increased selectivity towards lignin degradation in comparison to independently applied Fenton treatment. This could be a significant advantage for a bottleneck in the current valorization of biomass.

The depletion of fossil fuel reserves and severe environmental damage, resulting in climate change and global warming lead to a necessary shift to alternative renewable resources. Lignocellulose is a valuable feedstock for biorefineries, but its conversion is hindered by the limitations of conventional pretreatments lacking selectivity. This step should also be cost-effective and sustainable. In this paper, combined advanced oxidation techniques were applied for the treatment of corn stalks as a pretreatment for enzymatic hydrolysis. Their effect on delignification and cellulose digestibility was monitored. The combined non-thermal plasma/Fenton treatment appears to be suitable for breaking the complex lignocellulose structure, with a lignin content decrease of 39%. This treatment enhanced carbohydrate hydrolysis, resulting in 2.25 times increase in hexose yield, compared to the untreated sample. Long-term plasma treatment positively affected the textural properties, total porosity, and pore size diameter, of lignocellulose biomass. It enables the creation of materials with a stable system of pores and channels, for the unhindered diffusion of large organic molecules such as enzymes. Additionally, a combination of plasma treatment with Fenton reaction increased selectivity towards lignin degradation in comparison to independently applied Fenton treatment. This could be a significant advantage for a bottleneck in the current valorization of biomass.

The depletion of fossil fuel reserves and severe environmental damage, resulting in climate change and global warming lead to a necessary shift to alternative renewable resources. Lignocellulose is a valuable feedstock for biorefineries, but its conversion is hindered by the limitations of conventional pretreatments lacking selectivity. This step should also be cost-effective and sustainable. In this paper, combined advanced oxidation techniques were applied for the treatment of corn stalks as a pretreatment for enzymatic hydrolysis. Their effect on delignification and cellulose digestibility was monitored. The combined non-thermal plasma/Fenton treatment appears to be suitable for breaking the complex lignocellulose structure, with a lignin content decrease of 39%. This treatment enhanced carbohydrate hydrolysis, resulting in 2.25 times increase in hexose yield, compared to the untreated sample. Long-term plasma treatment positively affected the textural properties, total porosity, and pore size diameter, of lignocellulose biomass. It enables the creation of materials with a stable system of pores and channels, for the unhindered diffusion of large organic molecules such as enzymes. Additionally, a combination of plasma treatment with Fenton reaction increased selectivity towards lignin degradation in comparison to independently applied Fenton treatment. This could be a significant advantage for a bottleneck in the current valorization of biomass.

Sustainable plasma-catalytic NH3 synthesis is receiving an increasing amount of interest as a greener alternative for the conventional Haber-Bosch (HB) process. However, the best energy efficiency for the plasma synthesis reported so far is still low compared to the one of HB. This research was conducted to experimentally investigate one of the plasma process rate-limiting steps, which is N2 bond breaking. This study aimed at identifying the enhancing-surface reactions as well as limiting surface reactions such as H-inhibition. Ru/CeO2 and Ru/Ti-CeO2 were tested in a packed-bed DBD reactor to investigate the influence of TiO2 addition, which possibly prevented H-inhibition, and simultaneously enhanced different surface reactions. Variations of feed gas ratios and designed operation schemes were studied to elucidate the effect of the catalyst composition. Results showed that Ru/Ti-CeO2 outperformed Ru/CeO2 in terms of energy consumption and a N2-rich atmosphere was needed to obtain minima of 84.5 MJ mol−1 and 126.5 MJ mol−1, respectively. The addition of TiO2 in the catalysts provided more surface sites for H2 to adsorb on, which was identified as main reason for improving the energy efficiency of the plasma-catalytic NH3 synthesis. Three detailed reaction mechanisms were proposed to elaborate on the behavior between N2-rich plasma and Ru/Ti-CeO2.

Natural clinoptilolite (CLI) exhibited a high efficacy in ciprofloxacin (CIP) removal from aqueous solution by adsorption. However, the regeneration of the spent adsorbent was a challenge since the adsorption occurred via electrostatic interactions and ion-exchange reaction. Herein, the feasibility of non-thermal plasma (NTP) was studied for the regeneration of ciprofloxacin-containing clinoptilolite (CIP-CLI) in five successive adsorption/NTP regeneration cycles. The NTP treatments were performed using a surface dielectric barrier discharge (SDBD) operating at atmospheric pressure in air. Plasma discharge gap, sample mass, and electrode surfaces were varied to find optimal regeneration parameters. For the plasma source with an electrode surface of 37.2 cm2, the 2 mm electrode gap and 20 min of plasma treatment were found as optimal parameters (sample mass of 0.2 g). The plasma treatment did not affect clinoptilolite features which were concluded from a study of textural properties and powder X-ray diffraction (PXRD) analysis. X-ray photoelectron spectroscopy (XPS) showed a decrease of total carbon content with around 10% of carbon residual left on the surface. The CLI adsorption capacity can be regenerated to at least 90% of its initial capacity during the five successive cycles, showing the involvement of plasma reactive species in decomposition of adsorbed CIP.

Surface functionalization or modification to introduce more oxygen-containing functional groups to biochar is an effective strategy for tuning the physico-chemical properties and promoting follow-up applications. In this study, non-thermal plasma was applied for biochar surface carving before being used in contaminant removal and energy storage applications. The results showed that even a low dose of plasma exposure could introduce a high number density of oxygen-functional groups and enhance the hydrophilicity and metal affinity of the pristine biochar. The plasma-treated biochar enabled a faster metal-adsorption rate and a 40% higher maximum adsorption capacity of heavy metal ion Pb2+. Moreover, to add more functionality to biochar surface, biochar with and without plasma pre-treatment was activated by KOH at a temperature of 800 °C. Using the same amount of KOH, the plasma treatment resulted in an activated carbon product with the larger BET surface area and pore volume. The performance of the treated activated carbon as a supercapacitor electrode was also substantially improved by > 30%. This study may provide guidelines for enhancing the surface functionality and application performances of biochar using non-thermal-based techniques.[Figure not available: see fulltext.]

Anthropogenic greenhouse gas emissions have caused changes to the Earth's climate, resulting in catastrophic weather events that are becoming more frequent and intense. Developing carbon-neutral processes for CO2 conversion powered by renewable energy is one way of attaining a circular economy, as waste CO2 is converted to a new carbon-containing product, without also being created as a by-product during the process. Plasma-catalysis is gaining increasing interest for CO2 conversion and utilisation under mild conditions, particularly CO2 conversion to green chemicals and fuels using renewable hydrogen, as this electrified process can easily be combined with clean and renewable energy to ensure a carbon-neutral process. Previous studies have mainly focussed on the production of methane from CO2 and H2; however, ethane (C2H6) is a much more valuable product. In this work, we report a non-thermal plasma-catalytic process for the conversion of CO2 into C2H6 in a dielectric barrier discharge (DBD) reactor. The influence of a variety of alumina-supported metal catalysts (Ru, Cu, Ni and Fe) on the plasma-catalytic CO2 hydrogenation to C2H6 was evaluated. The Ru catalyst attained the highest selectivity towards C2H6, at almost 40%. The Ru catalyst also increased the energy efficiency of the process to around 18%, in comparison to the plasma reaction using pure alumina (12%). The Ru catalyst also achieved the highest H2 conversion at 29%. Plasma-assisted production of C2H6 is a new promising process for the utilisation of CO2 via carbon-neutral electrified gas conversion.

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

Plasma is regularly alluded to as the fourth form of matter. Its bounty presence in nature along with its potential antibacterial properties has made it a widely utilized disinfectant in clinical sciences. Thermal plasma and nonthermal (or cold atmospheric) plasma (NTP) are two types of plasma. Atoms and heavy particles are both available at the same temperature in thermal plasma. Cold atmospheric plasma (CAP) is intended to be nonthermal since its electrons are hotter than the heavier particles at ambient temperature. Direct barrier discharge (DBD), atmospheric plasma pressure jet (APPJ), etc. methods can be used to produce plasma, however, all follow a basic concept in their generation. This review focuses on the anticipated uses of cold atmospheric plasma in dentistry, such as its effectiveness in sterilizing dental instruments by eradicating bacteria, its advantage in dental cavity decontamination over conventional methods, root canal disinfection, its effects on tooth whitening, the benefits of plasma treatment on the success of dental implant placement, and so forth. Moreover, the limitations and probable solutions has also been anticipated. These conceivable outcomes thus have proclaimed the improvement of more up-to-date gadgets, for example, the plasma needle and plasma pen, which are efficient in treating the small areas like root canal bleaching, biofilm disruption, requiring treatment in dentistry.

Plasma is regularly alluded to as the fourth form of matter. Its bounty presence in nature along with its potential antibacterial properties has made it a widely utilized disinfectant in clinical sciences. Thermal plasma and nonthermal (or cold atmospheric) plasma (NTP) are two types of plasma. Atoms and heavy particles are both available at the same temperature in thermal plasma. Cold atmospheric plasma (CAP) is intended to be nonthermal since its electrons are hotter than the heavier particles at ambient temperature. Direct barrier discharge (DBD), atmospheric plasma pressure jet (APPJ), etc. methods can be used to produce plasma, however, all follow a basic concept in their generation. This review focuses on the anticipated uses of cold atmospheric plasma in dentistry, such as its effectiveness in sterilizing dental instruments by eradicating bacteria, its advantage in dental cavity decontamination over conventional methods, root canal disinfection, its effects on tooth whitening, the benefits of plasma treatment on the success of dental implant placement, and so forth. Moreover, the limitations and probable solutions has also been anticipated. These conceivable outcomes thus have proclaimed the improvement of more up-to-date gadgets, for example, the plasma needle and plasma pen, which are efficient in treating the small areas like root canal bleaching, biofilm disruption, requiring treatment in dentistry.

Plasma is regularly alluded to as the fourth form of matter. Its bounty presence in nature along with its potential antibacterial properties has made it a widely utilized disinfectant in clinical sciences. Thermal plasma and nonthermal (or cold atmospheric) plasma (NTP) are two types of plasma. Atoms and heavy particles are both available at the same temperature in thermal plasma. Cold atmospheric plasma (CAP) is intended to be nonthermal since its electrons are hotter than the heavier particles at ambient temperature. Direct barrier discharge (DBD), atmospheric plasma pressure jet (APPJ), etc. methods can be used to produce plasma, however, all follow a basic concept in their generation. This review focuses on the anticipated uses of cold atmospheric plasma in dentistry, such as its effectiveness in sterilizing dental instruments by eradicating bacteria, its advantage in dental cavity decontamination over conventional methods, root canal disinfection, its effects on tooth whitening, the benefits of plasma treatment on the success of dental implant placement, and so forth. Moreover, the limitations and probable solutions has also been anticipated. These conceivable outcomes thus have proclaimed the improvement of more up-to-date gadgets, for example, the plasma needle and plasma pen, which are efficient in treating the small areas like root canal bleaching, biofilm disruption, requiring treatment in dentistry.

Plasma is the state of matter produced when molecules and atoms are energized to a point where their electrons escape and the constituent material becomes ionized. It is described as the fourth state of matter making up the vast majority of the observable universe, and over the past century has been studied and developed into usable human-scale applications. As a category, plasma exists in a thermal spectrum as ionization and unbound electrons are the defining characteristics. Thus, non-thermal plasmas made up of near room temperature ionized gasses formed through strong alternating electromagnetic fields make up one side of the spectrum and thermal plasmas that have heated materials to the point of ionizing constitute the other. This dissertation focuses on the application of non-thermal plasmas for reactive gas generation and nanomaterial synthesis, in addition to more fundamental studies of how the plasma interacts with solid interfaces or forms nanomaterials. The studies that this work is composed of are broken down into sections, the first of which is fundamental investigations of non-thermal plasma properties, such as in-situ monitoring of plasma-induced surface-heating via Raman-thermometry and investigations into nanomaterial growth mechanics when exposed to discontinuous (pulsing) plasma conditions. The second section puts the silicon nanomaterials produced via plasma to use in quantum dots, where the silicon nanocrystal is combined with non-toxic organic molecules to achieve record setting photon upconversion and investigates the fundamental mechanisms impacting this method of light conversion. Next, plasma-grown and commercial silicon nanomaterials are applied as a next generation lithium-ion battery anode material, where unanswered questions about carbon shell structure and solid electrolyte interphase growth are investigated with novel techniques of material production and analysis. Finally, the reactive gas output of a plasma is put to work as a cheap

Plasma is regularly alluded to as the fourth form of matter. Its bounty presence in nature along with its potential antibacterial properties has made it a widely utilized disinfectant in clinical sciences. Thermal plasma and nonthermal (or cold atmospheric) plasma (NTP) are two types of plasma. Atoms and heavy particles are both available at the same temperature in thermal plasma. Cold atmospheric plasma (CAP) is intended to be nonthermal since its electrons are hotter than the heavier particles at ambient temperature. Direct barrier discharge (DBD), atmospheric plasma pressure jet (APPJ), etc. methods can be used to produce plasma, however, all follow a basic concept in their generation. This review focuses on the anticipated uses of cold atmospheric plasma in dentistry, such as its effectiveness in sterilizing dental instruments by eradicating bacteria, its advantage in dental cavity decontamination over conventional methods, root canal disinfection, its effects on tooth whitening, the benefits of plasma treatment on the success of dental implant placement, and so forth. Moreover, the limitations and probable solutions has also been anticipated. These conceivable outcomes thus have proclaimed the improvement of more up-to-date gadgets, for example, the plasma needle and plasma pen, which are efficient in treating the small areas like root canal bleaching, biofilm disruption, requiring treatment in dentistry.

The conversion of biogas, mainly formed of CO2 and CH4, into high-value platform chemicals is increasing attention in a context of low-carbon societies. In this new paradigm, acetic acid (AA) is deemed as an interesting product for the chemical industry. Herein we present a fresh overview of the current manufacturing approaches, compared to poten- tial low-carbon alternatives. The use of biogas as primary feedstock to produce acetic acid is an auspicious alternative, representing a step-ahead on carbon-neutral industrial processes. Within the spirit of a circular economy, we propose and analyse a new BIO-strategy with two noteworthy pathways to potentially lower the environmental impact. The generation of syngas via dry reforming (DRM) combined with CO2 utilisation offers a way to produce acetic acid in a two-step approach (BIO-Indirect route), replacing the conventional, petroleum-derived steam reforming process. The most recent advances on catalyst design and technology are discussed. On the other hand, the BIO-Direct route offers a ground-breaking, atom-efficient way to directly generate acetic acid from biogas. Nevertheless, due to thermo- dynamic restrictions, the use of plasma technology is needed to directly produce acetic acid. This very promising ap- proach is still in an early stage. Particularly, progress in catalyst design is mandatory to enable low-carbon routes for acetic acid production.

The conversion of biogas, mainly formed of CO2 and CH4, into high-value platform chemicals is increasing attention in a context of low-carbon societies. In this new paradigm, acetic acid (AA) is deemed as an interesting product for the chemical industry. Herein we present a fresh overview of the current manufacturing approaches, compared to poten- tial low-carbon alternatives. The use of biogas as primary feedstock to produce acetic acid is an auspicious alternative, representing a step-ahead on carbon-neutral industrial processes. Within the spirit of a circular economy, we propose and analyse a new BIO-strategy with two noteworthy pathways to potentially lower the environmental impact. The generation of syngas via dry reforming (DRM) combined with CO2 utilisation offers a way to produce acetic acid in a two-step approach (BIO-Indirect route), replacing the conventional, petroleum-derived steam reforming process. The most recent advances on catalyst design and technology are discussed. On the other hand, the BIO-Direct route offers a ground-breaking, atom-efficient way to directly generate acetic acid from biogas. Nevertheless, due to thermo- dynamic restrictions, the use of plasma technology is needed to directly produce acetic acid. This very promising ap- proach is still in an early stage. Particularly, progress in catalyst design is mandatory to enable low-carbon routes for acetic acid production.

Lignocellulosic biomass is a cheap raw material that, thanks to its high carbohydrate content, can be used in fermentation to produce biofuels, biogas and other compounds. Its complex structure, including cellulose, hemicellulose and lignin, requires prior treatment of the biomass to facilitate hydrolysis to simple sugars. Today, biomass is only partially utilized and generates about 14% of the world ́s energy. This is because the most commonly used physical, chemical and physicochemical treatments are not sustainable. They are energy-consuming but still low in productivity and toxic inhibitors formed during these treatments could hinder later steps of fermentation. Biomass treatment with advanced oxidation techniques has great potential as an environmentally friendly, so-called "green" treatment. These processes generate reactive species (radicals, electrons, ions and peroxides) that attack cellulose, hemicellulose, and lignin components. In this work, the effects of non-thermal plasma, the Fenton process, and the combined treatment of corn stalks with non-thermal plasma/Fenton were compared. Grounded biomass of corn stalks was mixed with Fenton reagent and hydrogen peroxide at different ratios and subjected to non-thermal plasma treatment. Carbohydrate content was decreased in non-thermal plasma treated samples both with and without Fe2+. However, a specific biomass: Fe2+:H2O2 ratio was required to achieve the highest rate of lignocellulose decomposition. The cellulose and hemicellulose fractions were affected and reduced by the treatments studied but resulted in almost no changes in the cellulose crystallinity index. The lower lignin content and cellulose crystallinity allow for more efficient enzyme hydrolysis of the treated lignocellulose and new options for valorization in fermentations., Lignocelulozna biomasa predstavlja jeftinu sirovinu koja se može koristiti u fermentacionim procesima za dobijanje biogoriva, biogasa i drugih jedinjenja, zahvaljujući visokom sadržaju ugljenih hidrata. Složena struktura, koja uključuje celulozu, hemicelulozu i lignin, zahteva prethodni tretman biomase kojim se olakšava hidroliza do prostih šećera. Danas se biomasa samo delimično eksploatiše i generiše oko 14% energije na svetskom nivou. To je prevashodno zbog male održivosti najčešće korišćenih fizičkih, hemijskih i fizičko-hemijskih tretmana. Ovi procesi troše veliku količinu energije, imaju malu produktivnost, a toksični sporedni proizvodi koji nastaju tokom tretmana mogu ometati kasnije korake fermentacije. Tretman biomase naprednim oksidacionim procesima ima veliki potencijal kao ekološki prihvatljiv, tzv. „zeleni“ tretman. Tokom ovog procesa dolazi do stvaranja reaktivnih vrsta (radikala, elektrona, jona i peroksida), koje napadaju celulozu, hemicelulozu i lignin. U ovom radu upoređeni su efekti tretmana kukuruzne stabljike netermalnom plazmom, Fentonovim reagensom i kombinovanog tretmana netermalnom plazmom/Fentonreagensom.Samlevena biomasa kukuruzne stabljike pomešana je sa Fentonovim reagensom i vodonik peroksidom u različitim odnosima, a zatim je podvrgnuta tretmanu netermalnom plazmom. Sadržaj celuloze i hemiceluloze je značajno smanjen u uzorcima tretiranim netermalnom plazmom i u prisustvu i u odsustvu Fe2+. Ipak, najveći stepen redukcije lignoceluloze je postignut pri određenom odnosu biomasa:Fe2+:vodonik peroksid. Primenjeni tretmani su uticali i na hemiceluloznu frakciju, ostavljajući indeks kristaliničnosti celuloze skoro nepromenjenim. Niži sadržaj lignina i manji indeks kristaliničnosti celuloze omogućavaju efikasniju enzimsku hidrolizu tretirane lignoceluloze i nove načine za valorizaciju u fermentacionim procesima.

Lignocellulosic biomass is a cheap raw material that, thanks to its high carbohydrate content, can be used in fermentation to produce biofuels, biogas and other compounds. Its complex structure, including cellulose, hemicellulose and lignin, requires prior treatment of the biomass to facilitate hydrolysis to simple sugars. Today, biomass is only partially utilized and generates about 14% of the world ́s energy. This is because the most commonly used physical, chemical and physicochemical treatments are not sustainable. They are energy-consuming but still low in productivity and toxic inhibitors formed during these treatments could hinder later steps of fermentation. Biomass treatment with advanced oxidation techniques has great potential as an environmentally friendly, so-called "green" treatment. These processes generate reactive species (radicals, electrons, ions and peroxides) that attack cellulose, hemicellulose, and lignin components. In this work, the effects of non-thermal plasma, the Fenton process, and the combined treatment of corn stalks with non-thermal plasma/Fenton were compared. Grounded biomass of corn stalks was mixed with Fenton reagent and hydrogen peroxide at different ratios and subjected to non-thermal plasma treatment. Carbohydrate content was decreased in non-thermal plasma treated samples both with and without Fe2+. However, a specific biomass: Fe2+:H2O2 ratio was required to achieve the highest rate of lignocellulose decomposition. The cellulose and hemicellulose fractions were affected and reduced by the treatments studied but resulted in almost no changes in the cellulose crystallinity index. The lower lignin content and cellulose crystallinity allow for more efficient enzyme hydrolysis of the treated lignocellulose and new options for valorization in fermentations., Lignocelulozna biomasa predstavlja jeftinu sirovinu koja se može koristiti u fermentacionim procesima za dobijanje biogoriva, biogasa i drugih jedinjenja, zahvaljujući visokom sadržaju ugljenih hidrata. Složena struktura, koja uključuje celulozu, hemicelulozu i lignin, zahteva prethodni tretman biomase kojim se olakšava hidroliza do prostih šećera. Danas se biomasa samo delimično eksploatiše i generiše oko 14% energije na svetskom nivou. To je prevashodno zbog male održivosti najčešće korišćenih fizičkih, hemijskih i fizičko-hemijskih tretmana. Ovi procesi troše veliku količinu energije, imaju malu produktivnost, a toksični sporedni proizvodi koji nastaju tokom tretmana mogu ometati kasnije korake fermentacije. Tretman biomase naprednim oksidacionim procesima ima veliki potencijal kao ekološki prihvatljiv, tzv. „zeleni“ tretman. Tokom ovog procesa dolazi do stvaranja reaktivnih vrsta (radikala, elektrona, jona i peroksida), koje napadaju celulozu, hemicelulozu i lignin. U ovom radu upoređeni su efekti tretmana kukuruzne stabljike netermalnom plazmom, Fentonovim reagensom i kombinovanog tretmana netermalnom plazmom/Fentonreagensom.Samlevena biomasa kukuruzne stabljike pomešana je sa Fentonovim reagensom i vodonik peroksidom u različitim odnosima, a zatim je podvrgnuta tretmanu netermalnom plazmom. Sadržaj celuloze i hemiceluloze je značajno smanjen u uzorcima tretiranim netermalnom plazmom i u prisustvu i u odsustvu Fe2+. Ipak, najveći stepen redukcije lignoceluloze je postignut pri određenom odnosu biomasa:Fe2+:vodonik peroksid. Primenjeni tretmani su uticali i na hemiceluloznu frakciju, ostavljajući indeks kristaliničnosti celuloze skoro nepromenjenim. Niži sadržaj lignina i manji indeks kristaliničnosti celuloze omogućavaju efikasniju enzimsku hidrolizu tretirane lignoceluloze i nove načine za valorizaciju u fermentacionim procesima.

Lignocellulosic biomass is a cheap raw material that, thanks to its high carbohydrate content, can be used in fermentation to produce biofuels, biogas and other compounds. Its complex structure, including cellulose, hemicellulose and lignin, requires prior treatment of the biomass to facilitate hydrolysis to simple sugars. Today, biomass is only partially utilized and generates about 14% of the world´s energy. This is because the most commonly used physical, chemical and physicochemical treatments are not sustainable. They are energy-consuming but still low in productivity and toxic inhibitors formed during these treatments could hinder later steps of fermentation.Biomass treatment with advanced oxidation techniques has great potential as an environmentally friendly, so-called "green" treatment. These processes generate reactive species (radicals, electrons, ions and peroxides) that attack cellulose, hemicellulose, and lignin components. In this work, the effects of non-thermal plasma, the Fenton process, and the combined treatment of corn stalks with non-thermal plasma/Fenton were compared. Grounded biomass of corn stalks was mixed with Fenton reagent and hydrogen peroxide at different ratios and subjected to non-thermal plasma treatment. Carbohydrate content was decreased in non-thermal plasma treated samples both with and without Fe2+. However, a specific biomass: Fe2+:H2O2 ratio was required to achieve the highest rate of lignocellulose decomposition. The cellulose and hemicellulose fractions were affected and reduced by the treatments studied but resulted in almost no changes in the cellulose crystallinity index. The lower lignin content and cellulose crystallinity allow for more efficient enzyme hydrolysis of the treated lignocellulose and new options for valorization in fermentations., Lignocelulozna biomasa predstavlja jeftinu sirovinu koja se može koristiti u fermentacionim procesima za dobijanje biogoriva, biogasa i drugih jedinjenja, zahvaljujući visokom sadržaju ugljenih hidrata. Složena struktura, koja uključuje celulozu, hemicelulozu i lignin, zahteva prethodni tretman biomase kojim se olakšava hidroliza do prostih šećera. Danas se biomasa samo delimično eksploatiše i generiše oko 14% energije na svetskom nivou. To je prevashodno zbog male održivosti najčešće korišćenih fizičkih, hemijskih i fizičko-hemijskih tretmana. Ovi procesi troše veliku količinu energije, imaju malu produktivnost, a toksični sporedni proizvodi koji nastaju tokom tretmana mogu ometati kasnije korake fermentacije. Tretman biomase naprednim oksidacionim procesima ima veliki potencijal kao ekološki prihvatljiv, tzv. „zeleni“ tretman. Tokom ovog procesa dolazi do stvaranja reaktivnih vrsta (radikala, elektrona, jona i peroksida), koje napadaju celulozu, hemicelulozu i lignin. U ovom radu upoređeni su efekti tretmana kukuruzne stabljike netermalnom plazmom, Fentonovim reagensom i kombinovanog tretmana netermalnom plazmom/Fenton reagensom. Samlevena biomasa kukuruzne stabljike pomešana je sa Fentonovim reagensom i vodonik peroksidom u različitim odnosima, a zatim je podvrgnuta tretmanu netermalnom plazmom. Sadržaj celuloze i hemiceluloze je značajno smanjen u uzorcima tretiranim netermalnom plazmom i u prisustvu i u odsustvu Fe2+. Ipak, najveći stepen redukcije lignoceluloze je postignut pri određenom odnosu biomasa:Fe2+:vodonik peroksid. Primenjeni tretmani su uticali i na hemiceluloznu frakciju, ostavljajući indeks kristaliničnosti celuloze skoro nepromenjenim. Niži sadržaj lignina i manji indeks kristaliničnosti celuloze omogućavaju efikasniju enzimsku hidrolizu tretirane lignoceluloze i nove načine za valorizaciju u fermentacionim procesima.

Vibrational excitation represents an efficient channel to drive the dissociation of CO2 in a non-thermal plasma. Its viability is investigated in low-pressure pulsed discharges, with the intention of selectively exciting the asymmetric stretching mode, leading to stepwise excitation up to the dissociation limit of the molecule. Gas heating is crucial for the attainability of this process, since the efficiency of vibration-translation (V-T) relaxation strongly depends on temperature, creating a feedback mechanism that can ultimately thermalize the discharge. Indeed, recent experiments demonstrated that the timeframe of V-T non-equilibrium is limited to a few milliseconds at ca. 6 mbar, and shrinks to the mu s-scale at 100 mbar. With the aim of backtracking the origin of gas heating in pure CO2 plasma, we perform a kinetic study to describe the energy transfers under typical non-thermal plasma conditions. The validation of our kinetic scheme with pulsed glow discharge experiments enables to depict the gas heating dynamics. In particular, we pinpoint the role of vibration-vibration-translation relaxation in redistributing the energy from asymmetric to symmetric levels of CO2, and the importance of collisional quenching of CO2 electronic states in triggering the heating feedback mechanism in the sub-millisecond scale. This latter finding represents a novelty for the modelling of low-pressure pulsed discharges and we suggest that more attention should be paid to it in future studies. Additionally, O atoms convert vibrational energy into heat, speeding up the feedback loop. The efficiency of these heating pathways, even at relatively low gas temperature and pressure, underpins the lifetime of V-T non-equilibrium and suggests a redefinition of the optimal conditions to exploit the 'ladder-climbing' mechanism in CO2 discharges.

Lignocellulosic biomass is a cheap raw material that, thanks to its high carbohydrate content, can be used in fermentation to produce biofuels, biogas and other compounds. Its complex structure, including cellulose, hemicellulose and lignin, requires prior treatment of the biomass to facilitate hydrolysis to simple sugars. Today, biomass is only partially utilized and generates about 14% of the world´s energy. This is because the most commonly used physical, chemical and physicochemical treatments are not sustainable. They are energy-consuming but still low in productivity and toxic inhibitors formed during these treatments could hinder later steps of fermentation.Biomass treatment with advanced oxidation techniques has great potential as an environmentally friendly, so-called "green" treatment. These processes generate reactive species (radicals, electrons, ions and peroxides) that attack cellulose, hemicellulose, and lignin components. In this work, the effects of non-thermal plasma, the Fenton process, and the combined treatment of corn stalks with non-thermal plasma/Fenton were compared. Grounded biomass of corn stalks was mixed with Fenton reagent and hydrogen peroxide at different ratios and subjected to non-thermal plasma treatment. Carbohydrate content was decreased in non-thermal plasma treated samples both with and without Fe2+. However, a specific biomass: Fe2+:H2O2 ratio was required to achieve the highest rate of lignocellulose decomposition. The cellulose and hemicellulose fractions were affected and reduced by the treatments studied but resulted in almost no changes in the cellulose crystallinity index. The lower lignin content and cellulose crystallinity allow for more efficient enzyme hydrolysis of the treated lignocellulose and new options for valorization in fermentations., Lignocelulozna biomasa predstavlja jeftinu sirovinu koja se može koristiti u fermentacionim procesima za dobijanje biogoriva, biogasa i drugih jedinjenja, zahvaljujući visokom sadržaju ugljenih hidrata. Složena struktura, koja uključuje celulozu, hemicelulozu i lignin, zahteva prethodni tretman biomase kojim se olakšava hidroliza do prostih šećera. Danas se biomasa samo delimično eksploatiše i generiše oko 14% energije na svetskom nivou. To je prevashodno zbog male održivosti najčešće korišćenih fizičkih, hemijskih i fizičko-hemijskih tretmana. Ovi procesi troše veliku količinu energije, imaju malu produktivnost, a toksični sporedni proizvodi koji nastaju tokom tretmana mogu ometati kasnije korake fermentacije. Tretman biomase naprednim oksidacionim procesima ima veliki potencijal kao ekološki prihvatljiv, tzv. „zeleni“ tretman. Tokom ovog procesa dolazi do stvaranja reaktivnih vrsta (radikala, elektrona, jona i peroksida), koje napadaju celulozu, hemicelulozu i lignin. U ovom radu upoređeni su efekti tretmana kukuruzne stabljike netermalnom plazmom, Fentonovim reagensom i kombinovanog tretmana netermalnom plazmom/Fenton reagensom. Samlevena biomasa kukuruzne stabljike pomešana je sa Fentonovim reagensom i vodonik peroksidom u različitim odnosima, a zatim je podvrgnuta tretmanu netermalnom plazmom. Sadržaj celuloze i hemiceluloze je značajno smanjen u uzorcima tretiranim netermalnom plazmom i u prisustvu i u odsustvu Fe2+. Ipak, najveći stepen redukcije lignoceluloze je postignut pri određenom odnosu biomasa:Fe2+:vodonik peroksid. Primenjeni tretmani su uticali i na hemiceluloznu frakciju, ostavljajući indeks kristaliničnosti celuloze skoro nepromenjenim. Niži sadržaj lignina i manji indeks kristaliničnosti celuloze omogućavaju efikasniju enzimsku hidrolizu tretirane lignoceluloze i nove načine za valorizaciju u fermentacionim procesima.

In recent years, the applications of non-thermal plasma have been brought to light and have proven to be very promising in the biomedical field. Indeed, a plasma is composed of a large variety of reactive species, among them reactive oxygen and nitrogen species (RONS), that can act on a given sample. One of the possibilities involves the delivery of plasma-derived reactive species for cancer treatments to obtain a less invasive procedure and avoid damaging the healthy cells. This study focusses focuses on how gelatin-based composite hydrogels influence the stability and release of reactive species generated in biopolymer solutions by non-thermal plasma treatment. The biopolymer solutions composed of Dermatan and Hyaluronic acid are treated to increase the amount of RONS compared to Plasma Treated Liquids (PTL). The use of gelatin hydrogels is justified to create easy-to-handle implants, while avoiding the biopolymer solution to be washed out by the body fluids after implantation. All components are from biological sources, biocompatible and biodegradable to avoid undesired interactions with the human body. The investigation of the biopolymer storage capacity will target H2O2, NO2 - and NO3 - , generated by a cold atmospheric plasma fed with a mixture of He + 0.3 % of synthetic air. In addition, to evaluate the behavior of the gelatin hydrogels, degradation tests were performed. Then the evaluation of RONS generation and a stability study were achieved. The results were compared according to the biopolymer used to store the plasma along with the detection methods employed. During the experiments, an increase of the RONS generated in Dermatan and Hyaluronic acid solution was observed, compared to the ones generated in PBS. We could advance a potential continued release of the RONS from the hydrogels after 45 minutes in physiological conditions., En los últimos años han salido a la luz las aplicaciones del plasma no térmico, que han demostrado ser muy prometedoras en el campo biomédico. En efecto, un plasma está compuesto por una gran variedad de especies reactivas, entre ellas especies reactivas de oxígeno y nitrógeno (RONS), que pueden actuar sobre una muestra determinada. Una de las posibilidades es la incorporación de dichas especies reactivas derivadas del plasma en los tratamientos contra el cáncer para obtener un procedimiento menos invasivo y evitar dañar las células sanas. Este estudio se centra en cómo los hidrogeles compuestos a base de gelatina influyen en la estabilidad y la liberación de especies reactivas generadas en soluciones biopoliméricas mediante el tratamiento con plasma no térmico. Las soluciones de biopolímeros compuestas por Dermatan y ácido hialurónico son tratadas para aumentar la cantidad de RONS en comparación con los líquidos tratados con plasma. El uso de hidrogeles de gelatina se justifica para crear implantes fáciles de manipular, al mismo tiempo que se evita que la solución de biopolímeros sea arrastrada por los fluidos corporales después de la implantación. Todos los componentes son de origen biológico y biodegradables para evitar interacciones no deseadas con el cuerpo humano. La investigación de la capacidad de almacenamiento del biopolímero se centrará en el H2O2, NO2 - y NO3 - , generados por un plasma no térmico alimentado con una mezcla de He + 0,3 % de aire sintético. Además, para evaluar el comportamiento de los hidrogeles de gelatina, se realizaron ensayos de degradación. Luego se realizó la evaluación de la generación de RONS y un estudio de estabilidad. Los resultados se compararon en función del Biopolímero utilizado para almacenar el plasma junto con los métodos de detección empleados. Durante los experimentos, se observó un aumento de los RONS generados en la solución de Dermatan y ácido hialurónico, en comparación con los generados en PBS. Pudimos avanzar una, En els darrers anys, la tecnologia de plasma no tèrmic ha sorgit amb un gran potencial en aplicacions en el camp biomèdic. El plasma està compost per una gran varietat d’espècies reactives, entre les quals trobem espècies reactives d’oxigen i nitrogen (RONS), que poden actuar sobre una mostra determinada. Entre les aplicacions mèdiques d’aquesta tecnologia podem trobar l’ús d’aquestes espècies reactives derivades del plasma en tractaments contra el càncer amb l’objectiu de desenvolupar procediments menys invasius i menys agressius ja que s’evita danyar les cèl·lules sanes. Aquest treball, es centra en com hidrogels compòsits basats en gelatina influeixen en l’estabilitat i l’alliberament d’espècies reactives generades en solucions de biopolímers mitjançant el tractament amb plasma no tèrmic. Aquestes solucions biopolimèriques compostes per Dermatan i Àcid Hialurònic, seran tractades per augmentar la quantitat de RONS en comparació amb els líquids tractats amb plasma. L’ús d’hidrogels de gelatina es justifica per crear implants que siguin fàcils de manipular i per evitar que la solució de biopolímers sigui arrossegada pels fluids corporals després d’implantar-los. Tots els components amb els que es treballarà son d’origen biològic, biocompatibles i biodegradables per evitar interaccions no desitjades amb el cos humà. La investigació de la capacitat d’emmagatzematge de les solucions de biopolímers es va centrar en el H2O2, NO2 - i NO3 - , els quals seran generats amb un plasma no tèrmic alimentat amb una barreja d’He + 0.3 % d’aire sintètic. A més, per avaluar el comportament dels hidrogels de gelatina, es van fer assajos de degradació. Després es va avaluar la generació i l’estabilitat dels RONS produïts. Els resultats es van comparar en funció del biopolímer utilitzat per emmagatzemar RONS juntament amb els mètodes de detecció emprats. Durant els experiments, es va observar un augment dels RONS generats a la solució de Dermatan i àcid hialurònic, en comparació amb e, Incoming

Natural clinoptilolite (CLI) exhibited a high efficacy in ciprofloxacin (CIP) removal from aqueous solution by adsorption. However, the regeneration of the spent adsorbent was a challenge since the adsorption occurred via electrostatic interactions and ion-exchange reaction. Herein, the feasibility of non-thermal plasma (NTP) was studied for the regeneration of ciprofloxacin-containing clinoptilolite (CIP-CLI) in five successive adsorption/NTP regeneration cycles. The NTP treatments were performed using a surface dielectric barrier discharge (SDBD) operating at atmospheric pressure in air. Plasma discharge gap, sample mass, and electrode surfaces were varied to find optimal regeneration parameters. For the plasma source with an electrode surface of 37.2 cm2, the 2 mm electrode gap and 20 min of plasma treatment were found as optimal parameters (sample mass of 0.2 g). The plasma treatment did not affect clinoptilolite features which were concluded from a study of textural properties and powder X-ray diffraction (PXRD) analysis. X-ray photoelectron spectroscopy (XPS) showed a decrease of total carbon content with around 10% of carbon residual left on the surface. The CLI adsorption capacity can be regenerated to at least 90% of its initial capacity during the five successive cycles, showing the involvement of plasma reactive species in decomposition of adsorbed CIP.

We study pentane depletion using a hybrid plasma system based on a surface dielectric barrier discharge (SDBD), with and without a catalyst, and as a function of plasma power and alkane concentration. We evaluate pentane decomposition efficiency based on plasma power and quantify the role of the catalyst in the resulting depletion of intermediate products. Analyses of the temporal evolution of pentane and the intermediate decomposition products allow us to estimate the corresponding decomposition rates according to the plasma parameters. We find that depletion efficiency increases as a function of pentane concentration. Furthermore, it is shown that the catalytic processes are responsible for a significant increase in the depletion rates of the intermediate reaction products, thus contributing to the total abatement process of pentane.

Optical diagnostics techniques based on coded imaging were developed and applied for plasma-related phenomena and applications. The signal of interest is first encoded with a sinusoid pattern either by structured laser illumination or implement of a diffractive optical element, such as a grating, along the optical path of the signal. The coded signal will then be extracted from the raw data by a lock-in based algorithm, such as frequency recognition algorithm for multipleexposures (FRAME). Two types of non-thermal plasma sources, i.e., gliding arc discharges and nanosecond pulsed discharges, were investigated. Volumetric information of molecular distributions around a gliding arc was captured using laser-induced fluorescence with structured illumination and FRAME. Laser scattering imaging during the formation of a nanosecond pulsed discharge on a at methane-air flame was extracted from luminous plasma emission using structured laser illumination. Furthermore, a technique named periodic shadowing was applied for streak camera measurements, where both higher temporal contrast and effective dynamic range were achieved. The gliding arc plasma discharge was also applied in an industrial prototype burner as plasma-assisted combustion has been proven to be a promising technique to increase energy efficiency as well as reduce environmentally harmful emission. With the help of 0.1% additional energy, the lean blow-out limit of a hundred kilowatt burner was extended from a global equivalence ratio of 0.47 to 0.45.

Plasma is regularly alluded to as the fourth form of matter. Its bounty presence in nature along with its potential antibacterial properties has made it a widely utilized disinfectant in clinical sciences. Thermal plasma and nonthermal (or cold atmospheric) plasma (NTP) are two types of plasma. Atoms and heavy particles are both available at the same temperature in thermal plasma. Cold atmospheric plasma (CAP) is intended to be nonthermal since its electrons are hotter than the heavier particles at ambient temperature. Direct barrier discharge (DBD), atmospheric plasma pressure jet (APPJ), etc. methods can be used to produce plasma, however, all follow a basic concept in their generation. This review focuses on the anticipated uses of cold atmospheric plasma in dentistry, such as its effectiveness in sterilizing dental instruments by eradicating bacteria, its advantage in dental cavity decontamination over conventional methods, root canal disinfection, its effects on tooth whitening, the benefits of plasma treatment on the success of dental implant placement, and so forth. Moreover, the limitations and probable solutions has also been anticipated. These conceivable outcomes thus have proclaimed the improvement of more up-to-date gadgets, for example, the plasma needle and plasma pen, which are efficient in treating the small areas like root canal bleaching, biofilm disruption, requiring treatment in dentistry.

Sauberes Wasser ist unabdingbar für die menschliche Gesundheit, Ökosysteme und wirtschaftliche Entwicklung. Der prognostizierte Anstieg des globalen Wasserbedarfs und Abwasseraufkommens ist daher eine besorgniserregende Entwicklung. Um diese Probleme zu bewältigen, sind sowohl punktuelle als auch diffuse Abbaumechanismen und -verfahren von Verunreinigungen von existentieller Bedeutung. Eine ganzheitliche Betrachtung der Wasseraufbereitung, die jeden Mechanismus adäquat und nachhaltig beleuchtet, ist jedoch notwendig. In dieser Dissertation wurden verbesserte punktuelle Aufbereitungsmethoden - Membranfiltration, Adsorptionssysteme, fortgeschrittene Oxidationsprozesse (advanced oxidation processes, AOP) und kombinierte Lösungen - auf ihre Anwendbarkeit für verschiedene Wasseraufbereitungszwecke getestet; die daraus gewonnenen Erkenntnisse haben zu einem vertieften mechanistischen Verständnis dieser Systeme beigetragen. Zusätzlich wurde die diffuse Schadstoffminderung durch natürlichen Abbau im Grundwasser bewertet. Verschiedene häufig in Wasser oder Abwasser vorkommende Schadstoffe (organische Mikroschadstoffe, Schwermetalle, Krankheitserreger, oder harmlose Modellsubstanzen) wurden mit mindestens einem der untersuchten Verfahren deutlich reduziert. Die entwickelten Mehrkanal-Mikro-/Ultrafiltrationsmembranen (MCM) aus Polyvinylidenfluorid (PVDF) eignen sich beispielsweise für die Entfernung von kolloidalen Substanzen durch Größenausschluss. Vergaserkohle aus einem Schwebefestbettprozess wies wiederum hohe Entfernungsraten (> 90 %) von Pharmazeutika und Industriechemikalien aus Abwasser auf und zeichnet sich somit als Bioadsorbens aus. Zusätzlich konnte ein vielversprechender AOP-Reaktor - nicht-thermisches Plasma mit Fernentladung - Mikroschadstoffe (> 90 %) und Arsen (> 98 %) aus Abwasser oder dotiertem Leitungswasser bei hoher Energieeffizienz in Kombination mit Membranen und Koagulation entfernen. Die Erkenntnisse aus der Herstellung von Polymermembranen wurden auß, Fresh water is crucial for human health, ecosystems, and economic development. However, growing scarcity of water of adequate quality is an issue of global concern. Both focal and diffuse pollution reduction mechanisms and processes are indispensable for addressing the projected increase in fresh water demand and wastewater generation - a holistic view on water treatment, however, needs to encompass each mechanism adequately and sustainably. In this work, a deepened mechanistic understanding of enhanced focal treatment methods - membrane filtration, adsorption systems, advanced oxidation processes (AOP), and combined solutions - has been achieved in the course of investigating their applicability in various water treatment purposes. Additionally, the diffuse contaminant abatement via natural attenuation in groundwater has been evaluated. Different contaminants that typically occur in water or wastewater (organic micropollutants, heavy metals, pathogens, or harmless model substances) were substantially reduced by applying at least one of the investigated processes. The developed multi-channel membranes (MCM) fabricated from the high-performance polymer polyvinylidene fluoride (PVDF), for instance, show micro-/ultrafiltration (MF/UF) characteristics and are suitable for the removal of colloids via size exclusion. Floating-fixed-bed gasification char (FFBC), an appealing bio-adsorbent, showed high removal (> 90 %) of pharmaceuticals and industrial chemicals from wastewater. Additionally, a promising AOP reactor - non-thermal plasma in a remote-discharge configuration - was able to remove micropollutants (> 90 %) and arsenic (> 98 %) from wastewater or spiked tap water at a high energy efficiency in combined processes with membranes and coagulation. Furthermore, the insights into polymeric membrane fabrication were extended to the production of mixed-matrix membranes (MMM) with activated carbon as filler material, which a maximum 60 min-average diclofenac (DCF) removal, Abweichender Titel laut Übersetzung der Verfasserin/des Verfassers, Arbeit an der Bibliothek noch nicht eingelangt - Daten nicht geprüft, Innsbruck, Univ., Diss., 2021

This study describes the phenomena involved during the regeneration of an aged industrial hydrodesulfurization catalyst (CoMoP/Al2O3) using a non-thermal plasma at a low temperature (200 °C). The changes occurring during regeneration were studied by characterizing spent, partially, and fully regenerated catalysts by XRD, Raman, TEM spectroscopy, and the coke deposited on the catalyst surface by Laser desorption/ionization time-of-flight mass spectrometry (LDI TOF/MS). The coke is a mixture of several polycyclic molecules, the heaviest with a coronene backbone, containing up to seven sulfur atoms. This kinetic study shows that the oxidation rate depends on the nature of the coke. Hence, explaining the formation of VOCs from heavy polycyclic carbon molecules without complete oxidation to CO2. However, XRD and Raman spectroscopies evidence CoMoO4 formation after a long treatment time, indicating hot spots during the regeneration.

CO2 reforming of CH4 in a non-thermal plasma process (e.g., dielectric barrier discharge, DBD) possesses dual benefits for our environment and energy needs. However, this process is strongly influenced by the dielectric structure of the DBD. Here, plasma CO2 reforming of CH4 has been performed in both single-dielectric and double-dielectric DBD (DBD-SD and DBD-DD) reactors under atmospheric pressure. Electrical and optical characterization, along with temperature measurements are performed to understand the influence of the DBD-SD and DBD-DD designs. Reactor performance for reforming is compared under different discharge powers. The results show that CO2/CH4 discharges in both DBD-SD and DBD-DD display typical filamentary microdischarges. Compared with the DBD-DD, the DBD-SD reactor exhibits a larger number and higher intensity of current pulses, which leads to a higher electron density and formation of reactive species. The highest conversion of CO2 (24.1 %) and CH4 (49.2 %) are achieved in the DBD-SD at a high discharge power (75 W). Moreover, higher selectivities of gaseous products are obtained in the DBD-DD, while the DBD-SD reactor shows a higher selectivity for liquid products, mainly including methanol and acetic acid. The highest energy efficiencies for reactant conversion (0.34 mmol/kJ), gaseous and liquid production formation (0.26 mmol/kJ and 0.015 mmol/kJ) are achieved in the DBD-SD reactor at a low discharge power (22 W), resulting from the low energy loss to the environment. However, the carbon deposited on the inner electrode surface in the DBD-SD would have an adverse influence on the reactor's performance. Further research on the optimization of the DBD reactor to establish an efficient plasma-catalysis system is required for industrial applications.

As an emerging technology that features the integration of microfluidics and non-equilibrium plasmas, microfluidic plasmas not only allow the precise and effective matter and heat transport via the microfluidic system, but also provide an extremely reactive medium full of high energy plasma-generated species. Therefore, they could open new pathways for chemical synthesis or chemical engineering processes that are hardly achievable by conventional methods. In this review, three main microfluidic plasma configurations are reviewed, including plasmas confined within microchannels, plasma jets beyond microchannels and microfluidic plasma arrays. The state-of-the-art diagnostic techniques for characterizing the microfluidic plasma are also examined. A broad range of applications of microfluidic plasmas of particular interest to chemistry and chemical engineering, such as nanomaterials fabrication, surface modification, chemical synthesis, environmental application, and micro total analysis systems, are discussed. The research gaps, bottlenecks and future perspectives of this novel technology are presented.

Lignocelullosic substrates are abundant and available in almost all parts of the world. However, we are still lacking efficient ways to valorise it due to recalcitrant nature of lignocelullose and presence of lignin which prevents enzymatic hydrolisis of cellulose. The compact nature of lignocellulose biomass prevents its wider application in biorefineries. Effective way to separate lignin from cellulose or to make cellulose more accessible to enzymes remains challenge. Among lignocellulose biomass, agricultural by-products like corn stalks or husks are considered more convenient as substrates as they contain less lignin then wood biomass and therefore can be more easily degraded. However, acid or alkaline hydrolysis are the most common approach in pretreatment of lignocellulose substrates, but they are not selective, lead to loss of significant amount of sugars and cause generation of inhibitory substances in hydrolysate. Additionally, acid and alkaline pretreatments are performed at elevated temperatures and have significant environmental impact.

Lignocellulosic substrates are abundant, and considered cheap sources of cellulose for biorefinery processes. However, their use is limited because of complex and interlinked structures of cellulose and lignin not easily accessible to enzymes for decomposition. Different chemical (acid, base, and enzymatic hydrolysis) and physical pretreatments (e.g. steam explosion, high pressure, non-thermal plasma) are used with limited success for degradation of lignin and better utilization of cellulose by microorganisms during fermentation. Poor selectivity, low efficiency, and environmental hazards are common problems in treatment of lignocellulose. Degradation of both cellulose and lignin, and formation of compounds which inhibit microorganisms in subsequent fermentation often occurs reducing the efficiency of bioprocessing. The use of a low-power atmospheric pressure plasma source (plasma needle) was investigated for treatment of corn stalks. Slices of corn stalks were subjected to non-thermal plasma treatment under different conditions. After the treatment, they are dyed and studied using light microscopy. AstraBlue® and safranin are used as dyes for staining of lignin in the absence and presence of cellulose, respectively. Plasma can degrade both cellulose and lignin but at different rates and treatment conditions can be tailored to achieve selectivity. This differential staining method is fast and simple. It enables us to examine how selective plasma treatments are and has a potential for screening of lignocellulose substrates, Lignocelulozni supstrati su široko rasprostranjeni i predstavljaju jeftine izvore celuloze za biorafinerijske postupke. Pa ipak, njihova upotreba je ograničena zbog kompleksnog sastava i izprepletanosti celuloznih i ligninskih komponenata što ih čini teško dostupnim za enzimsku razgradnju. Različiti hemijski (kisela, bazna i enzimska hidroliza) i fizički pretretmani (npr. tretman vodenom parom, visokim pritiskom, netermalnom plazmom) se koriste sa ograničenim uspehom za degradaciju lignina i bolje iskorišćenje celuloze pomoću mikroorganizama u toku fermentacije. Loša selektivnost, niska efikasnost i rizici vezani za uticaj na životnu sredinu su česti problemi prilikom tretmana lignoceluloznih supstrata. U toku ovih tretmana, često dolazi do istovremene razgradnje i celuloze i lignina i stvaranja inhibitornih jedinjenja koja negativno utiču na mikroorganizame u toku fermentacije, utičući značajno na efikasnost celokupnog procesa. U radu je ispitivana upotreba plazma izvora niske snage na atmosferskom pritisku (plazma igle) za tretman stabljika kukuruza. Preseci stabljika kukuruza su bili izloženi netermalnoj plazmi pri različitim uslovima. Nakon tretmana, preseci su obojeni i posmatrani svetlosnim mikroskopom. AstraBlue® i safranin su korišćeni kao boje za bojenje lignina u odsustvu i prisustvu celuloze, redom. Pokazano je da plazma može da razgradi i lignin i celulozu, ali u različitoj meri i da uslovi tretmana mogu biti kontrolisani tako da utiču na selektivnost razgradnje. Ovaj metod diferencijalnog bojenja je brz i jednostavan. On omogućava da se ispita selektivnost tretmana plazmom i ima potencijal za primenu u brzom skriningu lignoceluloznih supstrata

This study describes the phenomena involved during the regeneration of an aged industrial hydrodesulfurization catalyst (CoMoP/Al2O3) using a non-thermal plasma at a low temperature (200 °C). The changes occurring during regeneration were studied by characterizing spent, partially, and fully regenerated catalysts by XRD, Raman, TEM spectroscopy, and the coke deposited on the catalyst surface by Laser desorption/ionization time-of-flight mass spectrometry (LDI TOF/MS). The coke is a mixture of several polycyclic molecules, the heaviest with a coronene backbone, containing up to seven sulfur atoms. This kinetic study shows that the oxidation rate depends on the nature of the coke. Hence, explaining the formation of VOCs from heavy polycyclic carbon molecules without complete oxidation to CO2. However, XRD and Raman spectroscopies evidence CoMoO4 formation after a long treatment time, indicating hot spots during the regeneration.

Non-thermal plasmas, at their most ideal, are well understood; the realistic non-thermal plasma, that which is utilized across nearly all semi-conductor related industries as well as extensively in academia, remains thoroughly lacking that understanding, specifically, the non-thermal plasmas which synthesize and/or contain particulate matter, so-called dusty plasmas. This work addresses the marked difficulty in probing such discharges, presenting a design which results in a much more forgiving and simple system to probe and investigate—one which contains solely conductive dust and inert gases. This work studies potential conductive dust candidates and subsequent synthesis methods that adhere to these restrictions, resulting in a separate non-thermal plasma technique for the synthesis and injection of graphitic nanoparticles, as well as the inert gas, into the probed discharge. This work presents a home-built Langmuir probe capable of comprehensive measurements of the electron energy distribution function and important plasma parameters, with no measured degradation caused by a build-up of graphitic nanoparticles on the probe surface. This work confirms that the presence of dust leads to a decrease in electron density and, thus, an increase in the average electron temperature. Finally, this work studies the phenomenon of nanoparticle trapping, presents the first direct measurement of the particle floating potential in a dusty plasma, and represents a step towards understanding the incredibly complex effect of plasma-dust interactions.

Plasma-enabled liquefaction (PEL) is an emerging technology to transform renewable biomass into value-added fuels and chemicals through the plasma-induced highly-reactive chemical reactions. However, biomass dramatically ranges in the feedstock content in terms of hemicelluloses, cellulose, lignin, and ash, strongly affecting the liquefaction performance. Here, we performed the liquefaction of three typical lignocellulosic materials (sawdust, corncob and rice straw) with different feedstock contents in a PEL system. The influence of the catalyst content and the reaction time on the degradation of each biomass was investigated to understand the effect of the feedstock content on liquefaction yield. The results confirmed that the chemical contents of the lignocellulosic biomass especially the amount of lignin and ash significantly affected the liquefaction yield, the quality of liquid products and the distributions of the chemicals obtained. Compared with the PEL performance of corncob and rice straw, the higher energy yield (liquid fuels) was achieved in the PEL of sawdust, owing to higher content of lignin and less ash inside. Moreover, possible reaction pathways of lignocellulose biomass liquefaction were deduced based on the chemical analysis. Overall, this work demonstrated that the proposed PEL strategy could be a promising approach for rapid biomass conversion with high energy efficiencies.