Search Results (69)

The persistence of organochlorine pesticides, such as Aldrin and Dieldrin, in water bodies worldwide necessitates the development of efficient Advanced Oxidation Processes (AOPs) for water treatment or remediation. However, comparative studies evaluating the performance of distinct plasma discharge geometries against acoustic cavitation for the mineralization of these specific chlorinated cyclodienes remain scarce. This study investigates the comparative efficacy of four non-thermal technologies, ultrasound, dielectric barrier discharge (DBD) plasma, glow discharge plasma, and corona discharge plasma, for the simultaneous degradation of Aldrin and Dieldrin in a model contaminated aqueous solution (5 μg/L). All experiments followed a 3²-factorial design, and the residual concentrations of these pesticides were quantified by GC-MS after Solid-Phase Microextraction (SPME). All four methods achieved high degradation efficiencies, ranging from 92.5% to 100% for Aldrin and 92.6% to 99.2% for Dieldrin. Corona discharge plasma achieved the highest performance, resulting in 100% removal of Aldrin. However, ultrasound proved to be the most advantageous, achieving a 98% removal efficiency for both pesticides under its mildest conditions (3125 W/L ultrasonic power density for 3 min). The study confirmed that while Aldrin is highly susceptible to these technologies, Dieldrin remains the limiting factor for regulatory compliance. Chemical analysis did not conclusively identify any organic degradation by-products, suggesting that these AOPs may promote complete mineralization of the pollutants. Full article

Water convolvulus (Ipomoea aquatica Forssk.) is a fast-growing leafy vegetable valued for its nutritional and antioxidant properties; however, suboptimal seed physiology can hinder its germination and early growth. Non-thermal plasma (NTP) treatment is an eco-friendly seed-priming method that enhances seed performance and crop quality without the use of chemical inputs. This study evaluated the effects of NTP exposure (0, 5, 10, and 20 min) using a dielectric barrier discharge (DBD) plasma with an air gas flow rate of 1.5 lpm on the germination, seedling growth, pigment and protein content, nitrogen assimilation, and antioxidant capacity of water convolvulus. Plasma treatment of seeds increased germination in a time-dependent manner. The surface hydrophilicity improved with increasing treatment time. Seedlings grown from seeds treated for 10 min exhibited longer shoots (+10.1%) and roots (+17.8%). The shoot nitrate content increased by 66.3%. At 10 min, the total phenolics and flavonoids increased by 26.5% and 37.2%, respectively, with an accompanying increase in antioxidant activity, as measured by DPPH, ABTS, and FRAP assays. These findings demonstrate that a 10 min NTP treatment of seeds improves germination, growth, nutrient assimilation, phytochemical accumulation, and antioxidant activity in water convolvulus seedlings, highlighting its potential as a sustainable and chemical-free seed-priming technology with considerable potential to enhance the productivity and nutritional quality of plant microgreens in modern agriculture. Full article

Respiratory syncytial virus (RSV) is a major cause of severe respiratory infections, particularly in infants and young children. Although disinfection methods using alcohol and detergents are effective, their application in pediatric environments poses safety concerns. Ozone (O₃) has been employed for water treatment, food preservation, and air purification, but its efficacy against RSV has not been well studied. Here, we investigated the inactivation of RSV using a dielectric barrier discharge (DBD)-based ozone generator (SFG1210). The RSV A2 strain was spotted on glass coverslips and exposed to low-concentration ozone (0.5 ppm) for 1 h under controlled temperature (24.6~27.2 °C) and relative humidity (71.9~75.1%) conditions. Subsequent infectivity assays combined with immunochromatography showed that ozone exposure significantly reduced RSV infectivity. Specifically, viral titration assay of median tissue culture infectious dose (TCID₅₀) showed that RSV titers were reduced by more than 6 logs. In addition, biochemical analyses showed significant reductions in intact RSV genomic RNA and F protein levels after ozone treatment, suggesting that ozone inactivates RSV by damaging both the viral genome and surface proteins. These findings demonstrate the potential applicability of the SFG1210 ozone generator as an effective tool for surface disinfection of RSV, providing a safe, non-contact, and practical approach for infection control in healthcare and childcare settings. Full article

This study investigates the ozone generation characteristics of a nanosecond bipolar pulse-excited single-water electrode (dielectric barrier discharge) DBD reactor, with a particular focus on the effects of pulse width (T_p) on discharge behavior, plasma parameters, and ozone generation efficiency. The results indicate that the bipolar pulse voltage displays a symmetric alternating waveform, and the reactor demonstrates excellent thermal stability. Rotation temperature (T_rot) remains stable between 307 and 310 K (close to room temperature, which effectively suppresses O₃ thermal decomposition), while vibrational temperature (T_vib) stabilizes at 3120 ± 50 K (sufficient to ensure the electron energy required for O₂ dissociation). Electron excitation temperature (T_exc) increases with both the specific input energy (SIE) and T_p. At SIE = 200 J/L, extending T_p from 200 ns to 1000 ns results in an increase in T_exc from 2633 K to 2724 K. The ozone generation efficiency exhibits a “rise-then-decline” trend with increasing T_p. The optimal T_p is 500–600 ns, at which the maximum efficiency reaches 102 g/kWh (corresponding to SIE = 35.95 J/L), which is slightly higher than the peak efficiency of the unipolar pulse-driven water electrode reactor (99.64 ± 0.87 g/kWh, corresponding to SIE = 33.60 ± 1.53 J/L). This work innovatively applies nanosecond bipolar pulse excitation to a single-water electrode DBD reactor for ozone generation, an understudied configuration that integrates the discharge stability advantage of bipolar pulses and the superior cooling advantages of water electrodes. This study offers significant insights into the pulse power excitation of ozone generation. Full article

The present study evaluates a surface dielectric barrier discharge (SDBD) plasma system utilizing porous metal electrodes to enhance the performance of non-thermal plasma (NTP)-based water treatment. A custom high-voltage, variable-frequency power driver was developed to operate SDBD reactors featuring novel porous electrode configurations aimed at enhancing plasma–liquid interaction. Three types of porous metal electrodes—copper (60 ppi), copper (20 ppi), and nickel (60 ppi)—were investigated as ground electrodes to evaluate their impact on discharge behavior and treatment performance. Electrical characterization via Lissajous plot analysis and optical emission spectroscopy (OES) was used to assess plasma power and reactive species generation. Ozone measurement and hydroxyterephthalic acid (HTA) dosimetry confirmed the formation of O₃ and hydroxyl radicals (·OH), while methylene blue (MB) removal experiments quantified pollutant removal percentage and energy yield. Among the tested electrodes, the copper (20 ppi) configuration achieved the highest MB removal percentage of 95.07%, followed by nickel (60 ppi) with 90.53%, and copper (60 ppi) with only 27.55%. Correspondingly, the energy yield ($EY$) reached 0.349 g/kWh for copper (20 ppi) at 15 min of plasma exposure, 0.19 g/kWh for nickel (60 ppi) at 20 min, and 0.049 g/kWh for copper (60 ppi) at 15 min. These results highlight the potential of porous metal electrodes as effective design choices for optimizing plasma–liquid interaction in SDBD systems. The findings support the development of compact, energy-efficient plasma water purification technologies using air-fed, surface DBD configurations. Full article

Plasma has become an up-and-coming advanced oxidation technology for wastewater treatment. However, its efficiency is often limited due to the lack of high-performance catalytic materials. In this study, one-dimensional carbon nanofiber precursors were first fabricated via electrospinning, followed by the in situ growth of the Zn/Fe-MOF on their surfaces. After pyrolysis at different temperatures, a series of carbon-based catalysts (FeNFC) were obtained. This new type of catalyst possesses advantages such as high porosity, a large specific surface area, and mechanical stability. Using tetracycline (TTCH) as the target pollutant, the performance of the catalyst was evaluated in the dielectric barrier discharge (DBD) system. The study showed that the addition of FeNFC significantly increased the degradation rate of TTCH in the system. Comparing different pyrolysis temperatures, at 900 °C, the comprehensive performance of the catalyst (FeNFC-900) was the best (the kinetic constant was k_obs = 0.126 min⁻¹, and the removal rate of TTCH was 91.8% within 30 min). The catalytic performance was influenced by factors such as the dosage of the catalyst, the concentration of TTCH, the power of DBD, and the initial pH. The catalytic effect of the material increased within a certain range with the increase in the catalyst dosage. The increase in TTCH concentration led to a decrease in the catalytic performance. The higher the power of the DBD, the higher the removal rate of TTCH. Moreover, when the initial pH was strongly alkaline, the catalytic effect of the catalyst was the best (k_obs = 0.275 min⁻¹, and the removal rate of TTCH was 98.7% within 30 min). Ionic interference tests demonstrated the strong resistance of FeNFC to common water matrix components, while radical quenching experiments revealed that multiple reactive species contributed to TTCH degradation. This work has broad application prospects for enhancing the efficiency of DBD systems in the removal of TTCH. Full article

CuNiAl layered double hydroxide (LDH) catalysts were synthesized and employed for the oxidative destruction of cyanide ion (CN⁻) in wastewater in a plasma–catalyst loop reactor without the addition of any oxidizing agents. It was found that dielectric barrier discharge (DBD) could be used to degrade cyanide water due to the formation of oxidative species such as H₂O₂, ∙OH radicals, and O₃ in the plasma discharge zone. CuNiAl LDH catalysts were employed to destruct cyanide ion using oxidative species generated in situ in the loop reactor. The degradation time required for complete destruction of 100 ppm of CN⁻ was only 60 min, demonstrating the efficiency of the integration of both plasma and heterogeneous catalysts in this plasma–catalyst loop reactor. Full article

Seed germination and early seedling growth are pivotal stages that define crop establishment and yield potential. Conventional agrochemicals used to improve these processes often raise environmental concerns, highlighting the need for sustainable alternatives. In this study, we demonstrated that water treated with cylindrical dielectric barrier discharge (c-DBD) plasma, enriched with nitric oxide (NO) and reactive nitrogen species (RNS), markedly enhanced onion (Allium cepa) seed germination and seedling vigor. The plasma-treated water (PTW) promoted rapid imbibition, broke dormancy, and accelerated germination rates beyond 98%. Seedlings irrigated with PTW exhibited significantly increased biomass, root and shoot length, chlorophyll content, and antioxidant enzyme activities, accompanied by reduced lipid peroxidation. Transcriptomic profiling revealed that PTW orchestrated a multifaceted regulatory network by upregulating gibberellin biosynthesis genes (GA3OX1/2), suppressing abscisic acid signaling components (ABI5), and activating phenylpropanoid metabolic pathways (PAL, 4CL) and antioxidant defense genes (RBOH1, SOD). These molecular changes coincided with elevated NO₂⁻ and NO₃⁻ levels and finely tuned hydrogen peroxide dynamics, underpinning redox signaling crucial for seed activation and stress resilience. Our findings establish plasma-generated NO-enriched water as an innovative, eco-friendly technology that leverages redox and hormone crosstalk to stimulate germination and early growth, offering promising applications in sustainable agriculture. Full article

Reactive oxygen–nitrogen species (RONS) production in a Peltier-cooled hybrid dielectric barrier discharge (HDBD) reactor operated with humid air is characterized. Fourier-transform infrared spectroscopy (FTIR) is used to determine the RONS in the HDBD-produced gases. The presence of molecules ${\mathrm{O}}_3$, ${\mathrm{NO}}_2$, ${\mathrm{N}}_2$O, ${\mathrm{N}}_2{\mathrm{O}}_5$, and ${\mathrm{HNO}}_3$ is evaluated. The influence of HDBD reactor operation parameters on the FTIR result is discussed. The strongest influence of Peltier cooling on RONS chemistry is reached at conditions related to a high specific energy input (SEI): high voltage and duty cycle of plasma width modulation (PWM), and low gas flow. Both PWM and Peltier cooling can achieve a change in the chemistry from oxygen-based to nitrogen-based. ${\mathrm{N}}_2{\mathrm{O}}_5$ and ${\mathrm{HNO}}_3$ are detected at a low humidity of 7% in the reactor input air but not at humidity exceeding 90%. In addition to the FTIR analysis, the plasma-activated water (PAW) is investigated. PAW is produced by bubbling the HDBD plasma gas through 12.5 mL of distilled water in a closed-loop circulation at a high SEI. Despite the absence of ${\mathrm{N}}_2{\mathrm{O}}_5$ and ${\mathrm{HNO}}_3$ in the gas phase, the acidity of the PAW is increased. The pH value decreases on average by 0.12 per minute. Full article

The fluororesin membrane emerges as an ideal chemical-protective clothing material due to its excellent permeation resistance. However, using a fluororesin membrane with a low surface energy for compounding fabrics is very challenging. Herein, we demonstrate a strategy to modify the surface of a poly(ethylene-alt-tetrafluoroethylene) (ETFE) membrane by the atmospheric pressure dielectric barrier discharge (DBD) of plasma under different working voltages, processing times, and concentrations of acrylic acid (AA) in a helium (He) atmosphere. The increase in the hydrophilicity of the ETFE membrane is confirmed by the wettability test, which shows a significant decrease in the water contact angle, from 96° to 50°, after plasma modification. The interfacial T-peel strength of an ETFE membrane composited with polyester fabric increased from 0.53 N/cm to 13.64 N/cm after plasma modification. Significantly, the T-peel strength of the composite using a modified ETFE membrane with ultrasonic washing could still reach 11.75 N/cm. Various characterization methods clearly disclosed the physical and chemical changes on the ETFE membrane surface, such as introducing the polar -COOH group at a nano-level, improving the roughness, decreasing the ratios of the F/C element, and increasing the ratios of the O/C element, suggesting using nano-level grafted polyacrylic acid (g-PAA) on the surface of the membrane by DBD. Full article

Methylene blue (MB), a widely used industrial dye, is a persistent pollutant with documented toxicity to aquatic organisms and potential health risks to humans, even at ultra-trace levels. Conventional monitoring techniques such as UV–Vis spectroscopy and fluorescence emission suffer from limited sensitivity, typically failing to detect MB below ~10⁻⁷ M. In this study, we introduce a surface-enhanced Raman spectroscopy (SERS) platform based on silver nanowire (AgNW) substrates that enables MB detection over an unprecedented dynamic range—from 1.5 × 10⁻⁴ M down to 1.5 × 10⁻¹⁶ M. Raman mapping confirmed the presence of individual signal hot spots at the lowest concentration, consistent with the theoretical number of analyte molecules in the probed area, thereby demonstrating near-single-molecule detection capability. The calculated enhancement factors reached up to 1.90 × 10¹², among the highest reported for SERS-based detection platforms. A semi-quantitative calibration curve was established spanning twelve orders of magnitude, and this platform was successfully applied to monitor MB degradation during two advanced oxidation processes (AOPs): TiO₂ nanotube-mediated photocatalysis under UV irradiation and atmospheric-pressure dielectric barrier discharge (DBD) plasma treatment. While UV–Vis and fluorescence techniques rapidly lost sensitivity during the degradation process, the SERS platform continued to detect the characteristic MB Raman peak at ~1626 cm⁻¹ throughout the entire treatment duration. These persistent SERS signals revealed the presence of residual MB or partially degraded aromatic intermediates that remained undetectable by conventional optical methods. The results underscore the ability of AgNW-based SERS to provide ultra-sensitive, molecular-level insights into pollutant transformation pathways, enabling time-resolved tracking of degradation kinetics and validating treatment efficiency. This work highlights the importance of integrating SERS with AOPs as a powerful complementary strategy for advanced environmental monitoring and water purification technologies. By delivering an ultra-sensitive, low-cost sensor (<USD 0.16 per test) and promoting reagent-free treatment methods, this study directly advances SDG 6 (Clean Water and Sanitation) and SDG 12 (Responsible Consumption and Production). Full article

Ozone (O₃), a strong oxidizing agent, has found widespread applications since its structure was confirmed by Schubbe in 1839. It can be produced through ultraviolet radiation, electrochemical methods, or dielectric barrier discharge (DBD), with DBD being the most efficient for large-scale production due to its high stability. Ozone is widely used in environmental management, particularly in water treatment, air pollution control, and soil remediation. In water treatment, ozone effectively removes microorganisms and contaminants without generating secondary pollutants. In air pollution control, it degrades organic compounds in industrial waste and neutralizes toxic gases in automobile exhausts. Ozone also breaks down persistent pollutants like polycyclic aromatic hydrocarbons in soil, improving soil quality. However, challenges remain related to ozone’s stability and high production costs. Beyond environmental uses, ozone is critical in industries and medicine. It helps remove pathogens and heavy metals in wastewater treatment, extends shelf life and deactivates mycotoxins in food processing, and shows promise in medical fields like orthopedics and cancer therapy. In the power industry, ozone plays a key role in water treatment and air purification. Overall, ozone technology offers significant potential for both environmental and industrial applications. Full article

This study explores the development of biodegradable starch-based films treated with dielectric barrier discharge (DBD) plasma and incorporated with acerola residue and grape pomace extracts. The primary aim was to enhance the films’ physicochemical properties and introduce pH-sensing capabilities. Plasma treatment at 200 Hz for 20 min modified the films’ amylose content (by 13.2%), solubility (by 13.3%), contact angle (by 12.7%), moisture content (by 14.2%), and surface morphology. The addition of the extracts changed the short-range ordered structure parameters of the films (by 111.4%), solubility (by 11.1%), moisture content (by 18.4%), and water vapor permeability (by 6.1%). The films with acerola residue and grape pomace extracts exhibited good colorimetric responses for pH indication. The films with acerola residue extract tended to intensify the yellowish color, while those with grape pomace extract showed more significant color changes varying from purple to green. Integrating natural pigments like anthocyanins from grape pomace and carotenoids from acerola improved the films’ functional properties and provided a visual indication of food freshness through pH changes. Full article

Polypropylene (PP) membranes have found diverse applications, such as in wastewater treatment, lithium-ion batteries, and pharmaceuticals, due to their low cost, excellent mechanical properties, thermal stability, and chemical resistance. However, the intrinsic hydrophobicity of PP materials leads to membrane fouling and filtration flux reduction, which greatly hinders the applications of PP membranes. Dielectric barrier discharge (DBD) is an effective technique for surface modification of materials because it generates a large area of low-temperature plasma at atmospheric pressure. In this study, O₂ was added to nanosecond pulsed Ar DBD to increase its reactivity. Electrical and optical diagnostic techniques were used to study the discharge characteristics of the DBD at varying O₂ contents. The uniformity of the discharge was quantitatively analyzed using the observed discharge images. Water contact angle measurements were used to assess the surface hydrophilicity of polypropylene. The surface morphology and chemical composition of the PP materials before and after treatment were analyzed using field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The results show that the moderate addition of O₂ enhances surface hydrophilicity and the uniformity of the modification. By increasing the O₂ addition from 0% to 0.1%, the average power increased from 4.19 W to 5.79 W, and the energy efficiency increased from 17.78% to 21.51%. The water contact angle of the DBD-treated PP showed a tendency to decrease and then increase with increasing O₂ content, with the optimum O₂ addition determined to be 0.1%. Under this condition, the water contact angle of the PP surface decreased by 31.88°, which is 52.31% lower than the untreated surface. O₂ increases the number of oxygen-containing polar groups (-OH, C=O, and O-C=O) on the surface of the material, and deepens and densifies the grooves on the surface of the PP material, resulting in an increase in the hydrophilicity of the PP surface. Full article

The discharge of medical and domestic wastewater has resulted in increasing levels of pharmaceutical pollutants in water bodies. We combined dielectric barrier discharge (DBD) technology with an Fe³⁺/sodium sulfite oxidation system to address the limitations associated with traditional water treatment technologies in removing carbamazepine, exploring the application efficacy and mechanisms of this approach in carbamazepine degradation. Under optimized experimental conditions, our system achieved a 97% degradation efficiency for carbamazepine within 4 min, significantly outperforming both DBD and sodium sulfite standalone systems. Using response surface methodology to optimize experimental parameters, the effects of sodium sulfite concentration, pH, and Fe³⁺ concentration on degradation efficiency were assessed. Under optimal conditions, the system’s degradation efficiency was 2.5 times higher than that of individual systems. Hydroxyl and sulfate radicals contributed 65% and 85%, respectively, to carbamazepine degradation, while superoxide radicals contributed only 30%. The study demonstrated that this system effectively breaks down the molecular structure of carbamazepine. Eight primary intermediate degradation products were identified, and, as degradation progressed, the concentrations of these intermediates gradually decreased, ultimately achieving a mineralization rate exceeding 85%. This study not only provides an effective technical solution for rapidly treating recalcitrant organic pollutants in water but also offers new insights for environmental protection and the sustainable use of water resources while providing theoretical and experimental data for future related research. Full article