scholarly journals Cold Atmospheric Pressure Argon Plasma Jet Assisted Degradation of Malachite Green (MG) Aqueous Solution

2020 ◽  
Vol 2 (1) ◽  
pp. 51-61
Author(s):  
Vasu D ◽  
Ramkumar M.C ◽  
Arunkumar A ◽  
Navaneetha Pandiyaraj K

The oxidative degradation of cold atmospheric pressure plasma assisted degradation of malachite Green (MG) was investigated in this study. Cold atmospheric pressure plasma assisted MG degradation process was carried out as a function various plasma treatment time (05, 10, and 15 mins). The % of degradation and presence carbon content in the plasma treated MG was examined by UV-Visible spectroscopy (UV-Vis) and total organic carbon (TOC) analyzer. Optical emission spectrometer was used to identify formation of various reactive species during in situ plasma treatment. The higher degradation percentage of 90% was obtained after plasma treatment time of 15 min and value of TOC also found to decreased significantly with increasing plasma treatment time.  Toxicity of the plasma-treated MG aqueous solution samples was also examined by Staphylococcus aureus (S.aureus) bacteria.

2020 ◽  
Vol 10 (17) ◽  
pp. 6133
Author(s):  
Veronika Hahn ◽  
Daniel Grollmisch ◽  
Hannes Bendt ◽  
Thomas von Woedtke ◽  
Bodo Nestler ◽  
...  

The nursing of patients with wounds is an essential part of medical healthcare. In this context, cold atmospheric-pressure plasma sources can be applied for skin decontamination and stimulation of wound healing. One of these plasma devices is the commercially available kINPen® MED (neoplas tools GmbH), a cold atmospheric-pressure plasma jet which is approved as a medical device, class-IIa. For the plasma treatment, a sterile disposable spacer is recommended to ensure a constant and effective distance between plasma and skin. The disadvantage of this spacer is its form and size which means that the effective axis/area is not visible for the attending doctor or qualified personnel and consequently it is a more or less intuitive treatment. In addition, the suggested perpendicular treatment is not applicable for the attending specialist due to lack of space or patient/wound positioning. A concept of a sensory unit was developed to measure the treatment distance and to visualize the effective treatment area for different angles. To determine the effective area for the plasma treatment, some exemplary methods were performed. Thus, the antimicrobial (Staphylococcus aureus DSM799/ATCC6538) efficacy, reactive oxygen species (ROS) distribution and (vacuum) ultraviolet ((V)UV) irradiation were determined depending on the treatment angle. Finally, a simplified first approach to visualize the effective treatment area at an optimal distance was designed and constructed to train attending specialists for optimal wound area coverage.


2019 ◽  
Vol 82 (11) ◽  
pp. 1828-1836 ◽  
Author(s):  
ALIYU IDRIS MUHAMMAD ◽  
RUILING LV ◽  
XINYU LIAO ◽  
WEIJUN CHEN ◽  
DONGHONG LIU ◽  
...  

ABSTRACT The impact of cold atmospheric pressure plasma treatment on the inactivation kinetics of Bacillus cereus ATCC 14579 and the resulting quality changes was investigated in tiger nut (Cyperus esculentus L.) milk (TNM). The effect of input power (39, 43, and 46 W) and treatment time (0 to 270 s) was fitted using the Weibull model to represent the microbial kinetic inactivation in the treated TNM. Inactivation efficacy increased with an increase in treatment time and input power. A 5.28-log reduction was achieved at 39 to 46 W without significant changes in titratable acidity, whereas no reduction in titratable acidity was observed in the pasteurized sample. The inactivation kinetics was adequately described by the Weibull model. Higher input power of 43 and 46 W and 120 s of treatment resulted in marked decreases in pH, flavonoid concentration, and antioxidant activity compared with those parameters in pasteurized TNM. Increases in total color difference and phenolic concentrations also were observed. The results indicate that these changes were caused by the immanent plasma reactive species. This study provides valuable inactivation kinetics information for food safety assessment studies of B. cereus vegetative cells in TNM.


2007 ◽  
Vol 119 ◽  
pp. 123-126
Author(s):  
Soo Jin Park ◽  
Eun Jung Lee ◽  
Soo Han Kwon

In this work, the effects of atmospheric-pressure plasma treatment of polyimide films on surface and dielectric characteristics were studied by using X-ray photoelectron spectroscopy (XPS), surface free energies, and dielectric spectrometer. The total surface free energies and dielectric constants of plasma treated polyimide film were deareased with increasing the treatment time, which was mainly due to a lower London-dispersive component, while the specific component was increased. This could be attributed to an increase of the polar fluorine groups of polyimide per unit surface area. And the fluorine content of the polyimide film was increased with increasing the amount of the treatment time, resulting in decreasing dielectric constant of the film. It was found that the replacement of fluorine led to the decrease of the local electronic polarizability of polyimide, or to the increase of the free volume, which could be attributed to the relatively large volume of fluorine.


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