b. shokri

This study aimed to evaluate the effect of Vacuum Non-thermal Plasma (VNP) on surface decontamination of pistachios. Food safety is considered as a critical issue in food industry, and detoxification is an essential step during food processing. VNP is an effective method on decontamination of food and food processing. In this experiment, the ability of VNP to inactivate highly resistant indicator bacteria Geobacillus stearothermophilus and pistachio contaminating microorganisms was investigated. Firstly, the effect of Vacuum Non-thermal Air Plasma (VNAP) on G. stearothermophilus was investigated at power of 30, 50, 70, and 90W for 10, 20, 30, 40, and 50 minutes. The results indicate that the minimum dose of VNAP to completely inactivate G. stearothermophilus was 30 minutes and 50W. So, it can be considered as an Optimum Dose (OD) for VNAP treatment. Thereafter, OD was used to investigate the effects of VNAP and then Nacuum Non-thermal Oxygen Plasma (VNOP) on pistachio contaminating microorganisms. The pistachios samples exposed to VNAP in OD (50W for 30 minutes) showed 1.0 log microbial reduction, while the samples exposed to VNOP in OD showed 2.0 log reduction. Both VNAP and VNOP applied significantly decreased microbial load of pistachios, however, VNOP was more effective than VNAP. Therefore, VNOP in 50W for 30 minutes can be chosen as an OD. Pistachio samples were also analyzed by physicochemical properties in OD. In conclusion, VNP was found to be effective on decontamination of pistachios, with no significant effects on its properties.

One of the newest methods of waste management is benefiting from thermal plasma technology in gasification. Plasma gasification is a complicated process that requires much research. Plasma technology, meanwhile, can meet the energy and waste management needs of several communities, but the experimental study is not always feasible. In this study, an Aspen Plus model based on Gibbs free energy minimization is created in order to assess municipal waste and biomass as feedstocks. After validating the model, important parameters were examined which showed that increasing the amount of municipal waste in the feed can help improve the quality of syngas as the product of this process. The best steam to waste ratio for generating the highest amount of hydrogen production was obtained 2. It was also observed that the effect of steam-to-waste ratio on hydrogen production decreases with the increase of temperature above 800 degrees Celsius, and the increase of temperature in low steam-to-waste ratios has a greater effect on the amount of hydrogen production.

Polyester is one of the most important synthetic fibers extensively used in textile industry. Inkjet printing on polyester textile is performed either by direct or transfer approaches. The first method needs chemical surface treatment, while the latter uses transfer paper. In this article, direct sublimation inkjet printing (DSIP) on polyester textile has been studied to overcome the natural resource limitations and environmental problems by eliminating the need for transfer paper and chemical surface treatment. Polyester textile was surface treated using atmospheric-pressure plasma under air atmosphere. The effects of different factors including plasma speed, plasma power, and the number of treatments on the contact angle and K/S value have been investigated via experimental design method. Scanning electron microscopy (SEM), attenuated total reflection-fourier transform infrared (ATR-FTIR), and bleeding test showed that plasma power has the least effect on both K/S value and contact angle. The K/S values increased while the contact angle decreased by increasing the number of treatments and decreasing the plasma speed. Optical and scanning electron microscopy images also revealed that the treated textile using constant plasma power of 350 W, 60 plasma treatments and the plasma speed of 3 m/min showed the most printing thickness and the highest image resolution.

Cold plasma is a novel non-thermal technology for the food and packaging industry. In this study, the effects of argon glow discharge plasma on the mechanical properties, surface topography, chemical composition, film hydrophilicity, film solubility, and barrier properties of the starch films were examined. Plasma treatment improved Tensile Strength (TS) of the starch film. In contrast to TS, elongation at the break of the plasma-treated films remained unchanged. The surface roughness of starch film increased after plasma treatment. An apparent increase in the surface hydrophilicity was observed due to formation of oxygen-containing polar groups. FTIR analysis confirmed the increase in the oxygen containing groups in plasma-treated starch film. However, film surface hydrophilicity caused no significant change in the solubility of films. No significant difference was found in the barrier properties of the starch films. The evaluation of films modifications by glow discharge plasma will contribute to in-package decontamination studies of food products by plasma.

Thermal plasma gasification is a new and innovative method of waste management. In this study, the process of gasification of municipal solid waste in thermal plasma reactor has been simulated using Gibbs free energy minimization method with the help of Aspen Plus software. And validated with data from scientific sources. Most of the operational parameters such as air to waste ratio, reactor temperature, pressure to waste ratio and lower calorific value of gas have been studied by describing the manufactured syngas. The highest hydrogen content was 67%, which was calculated for gasification with steam plasma, And the lowest calorific value of the gas compared to 11/6 (MJ/Nm3 ) was calculated. Due to the very high temperature created by plasma, many pollutants that are a big problem for conventional methods do not affect this process.

Thymes are native plants of Iran and are considered as the most important medicinal plants due to their unique properties. In this study, morphological, ecological and essential oil percentage variation of 15 thyme populations (eight populations of T. kotschyanus, three populations of T. migricus, two populations of T. fedtschenkoi and one population of T. fallax and T. pubescens) from natural habitats of the northwest and west regions of Iran, were studied. For essential oil measurement, the flowering shoots of the populations were harvested during flowering season and the essential oils were extracted using Kelevenjer apparatus by distilled water for three hours. By examining the soil characteristics, climatic parameters and geographical position of the habitats, it was found that despite the geographical proximity, there were significant differences between the locations in which thymes were collected. This, along with genetic differences among the populations, led to a remarkable variation for all measured traits. There was negative correlation between essential oil percentage and inflorescence length. Using principal component analysis, the first three components explained 85% of the total variation. Using cluster analysis, the 15 populations divided into three groups. The populations in the third group had the highest values for most traits followed by the second and the first groups, respectively. According to results, Ghoghjeh population had the highest values for morphological characteristics. There was also a significant difference among the populations in terms of essential oil content. The essential oil percentage of the populations ranged from 0.92 to 2.82%. The highest values of essential oil 2.82%, 1.9% and 1.7% were obtained from Sardasht, Qushchi and Naghadeh populations, respectively. According to the results, the populations of Sardasht from T. fedtschenkoi, Qushchi from T. migricus and Naghadeh from T. kotschyanus had the highest essential oil content, and suggested for cultivation and using in related industries, pharmaceuticals, and improve breeding varieties.

In recent years, the increase of industrial effluents in the petrochemical sector, in particular, the leakage of oil and the draining of industrial effluents in rivers, has created serious environmental hazards and huge economic losses in the world. In the past decade, the use of hydrophobic and oleophilic fabrics has been considered as a way to clean up contaminants through the absorption and separation of pollutants from industrial effluents. In this research, the low-pressure plasma polymerization method based on eco-friendly materials like Polydimethylsiloxane was used to fabricate hydrophobic and oleophilic cotton fabric. Also a low-pressure oxygen plasma pre-treatment was performed before plasma polymerization to improve bonding between created layer and cotton fabric Contact angle test and absorption capacity test was used to represent hydrophobicity of coated fabric and to measure the absorbance ability of different oils. Also scanning electron microscopy (SEM) was used to observe morphological changes on the surface of cotton fibers and Infrared Fourier transform (FTIR-ATR) spectroscopy to detect the chemical bonds created on the surface of fibers. Water-oil separation efficiency test and laundering test have been conducted to determine the separation rate and to represent durability of coated cotton, respectively. The water contact angle of coated cotton fabric was 143±3 and approximately this high hydrophobicity behavior remained after 10 cycle laundering. Also SEM results showed that the surface of fibers was covered by a random distribution of several microscale structures or a hierarchical surface structure like the lotus leaf. Our Water-oil separation tests demonstrated that coated fabrics had separation efficiency between 80 until 100 percent for most of the industrial oil, even after 15 cycles at 250 c and 900 c. These results indicate that coated cotton fabrics with plasma polymerization method has a high potential for application in water-oil separation and selective oil absorption. The fabrics are promising for the development an environmental friendly and recyclable separation of oil from water.