Peony seed oil, known for its high nutritional value and low production yield, has become a crucial component in high-quality health products. Consequently, enhancing the extraction efficiency of ...peony seed oil has become an industry objective. Pulse electric field (PEF) technology, as a non-thermal extraction method, has shown promising advancements in improving plant oil yield by enhancing cell permeability. In this study, we designed a static parallel plate PEF treatment unit to process peony seed particles. By manipulating pulse voltage parameters, we investigated the effects of particle size and PEF strength on the oil yield. We also analyzed and evaluated tocopherol in the oil before and after treatment. The results demonstrated that PEF significantly increased the oil yield. Both treated and control groups exhibited gradually increased oil yields with decreasing particle size until reaching saturation at a certain particle size. Increasing voltage frequency did not have a significant impact on the oil yield; however, increasing voltage amplitude resulted in an optimal point for maximum oil yield. Analysis of oil composition indicated that PEF appropriately increased tocopherol content. These findings provide a foundation for further optimization of PEF parameters to assist in extracting peony seed oil and facilitate its industrial application.
On the basis of plasma technology, the progress of the volatile organic compounds' (VOCs') degradation by low‐temperature plasma alone is discussed first, including reactor types, influencing factors ...of plasma degradation of VOCs and the reaction mechanism between plasma and VOCs. Then, the research status of three VOC degradation technologies (catalysis, adsorption, and biotechnology) and their synergistic degradation of VOCs with plasma are reviewed, including the effect of catalyst position on VOC degradation, the interaction mechanism between plasma and catalyst; the factors affecting the adsorption of VOCs by carbon‐based adsorbents and zeolite, the degradation of VOCs by plasma‐assisted adsorbent; the features of different biological systems, the influencing factors of VOC degradation by the biotrickling system, and the degradation of VOCs by plasma‐assisted biotreatment. Finally, the prospects of developments in high‐tech based on plasma are discussed.
On the basis of plasma technology, this article introduces plasma‐related degradation technologies of volatile organic compounds (VOCs), including the influencing factors and reaction mechanism of VOC degradation by single plasma; the interaction mechanism between plasma and different catalyst systems; the factors affecting the adsorption of VOCs and its removal by plasma‐assisted adsorbent, and the synergistic degradation of VOCs with plasma and biological treatment technology
•Epoxy resin (EP) samples are treated by atmospheric pressures plasma jet (APPJ).•Flashover withstanding characteristics of epoxy resin samples are improved a lot after APPJ treatment.•Appropriate ...treatment conditions are important to modify EP samples by APPJ.•Both physical and chemical effects lead to the enhancement of flashover strength.
For enhancing the surface electric withstanding strength of insulating materials, epoxy resin (EP) samples are treated by atmospheric pressure plasma jet (APPJ) with different time interval from 0 to 300s. Helium (He) and tetrafluoromethane (CF4) mixtures are used as working gases with the concentration of CF4 ranging 0%-5%, and when CF4 is ∼3%, the APPJ exhibits an optimal steady state. The flashover withstanding characteristics of modified EP in vacuum are greatly improved under appropriate APPJ treatment conditions. The surface properties of EP samples are evaluated by surface roughness, scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and water contact angle. It is considered that both physical and chemical effects lead to the enhancement of flashover strength. The physical effect is reflected in the increase of surface roughness, while the chemical effect is reflected in the graft of fluorine groups.
Drying and sterilization are the main aspects to ensure the quality of pepper seeds, inhibit microbial growth and extend the storage cycle. Plasma can achieve rapid drying and efficient sterilization ...of materials, becoming a new non-thermal drying technology with potential. In this paper, an experimental study on the drying and sterilization of pepper seeds was carried out using discharge plasma. The effects of discharge plasma on the drying rate, surface sterilization effect and growth characteristics of treated seeds were analyzed. The results showed that discharge plasma significantly increased the drying rate of pepper seeds compared with natural drying. After the plasma-enhanced sterilization treatment, no scab pathogens were found on the seed surface. In addition, the results of germination experiments showed that plasma treatment did not negatively affect the growth of pepper seeds compared to untreated seeds.
A one-dimensional low-pressure CO 2 dielectric barrier discharge (DBD) plasma simulation model was established, and the discharge characteristics of the CO 2 DBD were simulated and particle ...distribution in the discharge plasma were probed. The simulation conditions were set as gap width d = 2mm, voltage amplitude u = 0.5kV, frequency f = 40kHz, and pressure p = 0.1 kPa. The results showed that the average electron density and electron temperature over the gap were consistent with the trends of discharge current and gap voltage, respectively. At the time of the discharge peak, the electron density appeared a maximum near the instantaneous anode, the ion density was 1-2 orders of magnitude higher than the electron density, and the electric field intensity increased approximately linearly from the instantaneous anode to the instantaneous cathode, which is characteristic of Townsend discharge. Neutral particle density (CO, O, C and O 2 ) had two peaks near the two electrodes, and its overall density in the gap showed a stepwise increase trend, which has a significant cumulative effect. The density of CO was basically equal to that of O, and much higher than that of C and O 2 . The density of vibrational excited CO 2 increased sharply when the discharge occurred, and it gradually decreased after the discharge was extinguished, eventually reaching a balance of production and consumption. The results can provide guidance for further understanding of the CO 2 discharge mechanism and its conversion.
CO2 constitutes around 95 % of the atmosphere on Mars, and its in-situ utilization is of great value. O2 is a significant target product transformed from CO2 that can support both human respiration ...and fuel combustion, its conversion mechanism remains unclear. In this study, using a dielectric barrier discharge (DBD) with parallel plate electrodes, simulation and experimental results are combined to discuss the discharge characteristics and CO2 conversion process, under Mars conditions. The DBD was driven by a repetitive frequency microsecond pulse voltage. According to the discharge current, the discharge process can be split into four stages, namely the positive (negative) discharge stage and the positive (negative) discharge extinguishing stage. With a contribution up to 98 % and primarily taking place in the positive discharge extinguishing stage, the recombination decomposition reaction of electron and CO+2 is the primary pathway of O2 synthesis. At the position near the edge of the cathode potential drop zone, electron impact ionization of CO2 ground state molecules dominates the formation of CO+2. Under the range of pulse parameters considered in this paper, increasing the pulse width can lengthen the time of recombination decomposition reaction of electron and CO+2 in positive discharge extinguishing stage, which is favorable for the formation of O2. Likewise, reducing the pulse's rising edge can increase the discharge intensity and CO+2 density, which is also favorable to O2 production.
•The discharge characteristics of DBD was analyzed, the plasma was further used to convert CO2 to O2 under Martian pressure.•The main pathway to produce O2 is recombination decomposition reaction of e and CO+2, with a contribution of more than 95 %.•CO+2 is mainly produced by electron impact ionization of ground state CO2 near the cathode drop region during discharge.
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•Both PEF and VSPB pretreatment accelerate drying of lily scales.•PEF pretreatment reduced the drying time of lily scales by 29.58% − 43.60%.•PEF pretreatment improved the quality of ...dried lily.•PEF and VSPB change lily’s ultrastructure and microstructure.
The effects of the non-thermal (pulsed electric field, PEF) and thermal pretreatment (vacuum steam pulsed blanching, VSPB) on the drying kinetics, quality attributes, and multi-dimensional microstructure of lily scales were investigated. The results indicate that both PEF and VSPB pretreatments improved the drying rate compared to untreated lily scales. Specifically, PEF pretreatment reduced the drying time by 29.58 % − 43.60 %, while VSPB achieved a 46.91 % reduction in drying time. PEF treatment facilitated the enhanced leaching of phenols and flavonoids compared to VSPB treated samples, thereby increasing antioxidant activity. The rehydration ratio of the dried lilies was improved with PEF and VSPB treatment, which closely related to the microstructure. Weibull distribution and Page model demonstrated excellent fit for the drying and rehydration kinetics of lily scales, respectively (R2 > 0.993). The analysis of multi-dimensional microstructure and ultrastructure confirmed the variations in moisture migration and phytochemical contents among different treatments. Consequently, this study offers insights into the technological support for the potential of non-thermal pretreatment in fruits and vegetables.
Mars has a special carbon dioxide environment. The surface and atmosphere of Mars contain a large amount of solid and gaseous carbon dioxide, which makes the in‐situ resource utilization of Martian ...carbon dioxide attract widespread attention. The conversion of carbon dioxide into fuel or high value‐added products through electrical discharge has become a research focus, in which numerical simulation is one of the important means to explain the experimental phenomenon and the mechanism. Therefore, a one‐dimensional fluid model was established in this paper to simulate the discharge and conversion of carbon dioxide under simulated Martian atmospheric pressure. The discharge mode, particle distribution, and discharge mechanism were studied by considering CO2 vibrational states and vibration relaxation reaction in the model. The results show that the discharge mode is glow discharge with an obvious cathode fall region, negative glow space, and positive column. The density of the four discharge products, C, O2, CO, and O, shows a step‐up trend, showing a significant cumulative effect, and the peak values appear near both electrodes. The density of vibrational states of CO2 molecule, which is highest in the neutral products, increases during the discharge stage and decreases after the discharge is extinguished. The temporal and spatial distribution of reaction rates shows that vibrational excitation, electronic excitation, and vibrational relaxation reactions dominate the loss and formation of CO2. The density of ground‐state CO2 decreases obviously in the discharge stage, and the minimum density appears near the instantaneous cathode. After the discharge is extinguished, the CO2 near the instantaneous cathode increases gradually.
CO2, which widely exists in Martian atmosphere, can be converted into O2 and fuel in‐situ for supporting the construction of Mars energy base. We use the plasma technology to activate CO2 molecules under mild conditions and generate the oxygen and the carbon monoxide. The discharge mode, particle distribution and discharge mechanism were studied, which will be helpful for further work about the in‐situ utilization of CO2 resources on Mars and the carbon emissions governance on Earth side.
The objective of this study was to examine the impact of corona discharge plasma (CDP) treatments of different durations (1, 3, 5, and 10 min) on the drying kinetics and quality attributes of lilies, ...including color, enzyme activities, total phenols content (TPC), and antioxidant activity. The microstructure of lilies under different CDP conditions were also investigated. As a result, all CDP treatments enhanced the drying rate relative to untreated lilies, and the shortest drying time of 7 h was obtained at CDP-3 minute samples. CDP treatment led to a higher retention in the TPC of dried lilies. Microstructural analysis revealed the formation of irregular micropores on the surface of the lilies after CDP treatment, which was closely associated with the accelerated drying rate and improved bioactive substances of the dried product. In conclusion, CDP has emerged as a novel and beneficial pretreatment technique that accelerates the drying process and enhances the nutritional qualities of dried lilies.
•Corona discharge plasma application was tested as a pretreatment to drying of lilies.•CDP pretreatment markedly enhanced the drying ratio and rehydration ratio.•The CDP treatment did not demonstrate a competitive advantage in terms of preserving color.•The use of CDP increased the preservation of TPC, TFC and antioxidant activity in dried lilies.
