Nitrate Capture Investigation in Plasma-Activated Water and Its Antifungal Effect on Cryptococcus pseudolongus Cells

This research investigated the capture of nitrate by magnesium ions in plasma-activated water (PAW) and its antifungal effect on the cell viability of the newly emerged mushroom pathogen Cryptococcus pseudolongus. Optical emission spectra of the plasma jet exhibited several emission bands attributable to plasma-generated reactive oxygen and nitrogen species. The plasma was injected directly into deionized water (DW) with and without an immersed magnesium block. Plasma treatment of DW produced acidic PAW. However, plasma-activated magnesium water (PA-Mg-W) tended to be neutralized due to the reduction in plasma-generated hydrogen ions by electrons released from the zero-valent magnesium. Optical absorption and Raman spectra confirmed that nitrate ions were the dominant reactive species in the PAW and PA-Mg-W. Nitrate had a concentration-dependent antifungal effect on the tested fungal cells. We observed that the free nitrate content could be controlled to be lower in the PA-Mg-W than in the PAW due to the formation of nitrate salts by the magnesium ions. Although both the PAW and PA-Mg-W had antifungal effects on C. pseudolongus, their effectiveness differed, with cell viability higher in the PA-Mg-W than in the PAW. This study demonstrates that the antifungal effect of PAW could be manipulated using nitrate capture. The wide use of plasma therapy for problematic fungus control is challenging because fungi have rigid cell wall structures in different fungal groups.

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Optical, electrochemical and third-order nonlinear optical studies of triphenylamine substituted zinc phthalocyanine

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424616500838 ◽

2016 ◽

Vol 20 (08n11) ◽

pp. 1173-1181 ◽

Cited By ~ 5

Author(s):

Narra Vamsi Krishna ◽

Puliparambil Thilakan Anusha ◽

S. Venugopal Rao ◽

L. Giribabu

Keyword(s):

Nonlinear Optical ◽

Emission Spectra ◽

Optical Emission ◽

Soret Band ◽

Laser Pulses ◽

Zinc Phthalocyanine ◽

Third Order ◽

Time Resolved ◽

Nlo Properties ◽

Scan Data

Zinc phthalocyanine possessing triphenylamine at its peripheral position has been synthesized and its optical, emission, electrochemical and third-order nonlinear optical (NLO) properties were investigated. Soret band was broadened due to the presence of triphenylamine moiety. Electrochemical properties indicated that both oxidation and reduction processes were ring centered. Emission spectra were recorded in different solvents and the fluorescence yields obtained were in the range of 0.02–0.17 while the time-resolved fluorescence data revealed radiative lifetimes of typically few ns. Third-order NLO properties of this molecule have been examined using the Z-scan technique with picosecond (ps) and femtoseocnd (fs) pulses. Closed and open aperture Z-scan data were recorded with 2 ps/1 50 fs laser pulses at a wavelength of 800 nm and NLO coefficients were extracted from both the data. Our data clearly suggests the potential of this molecule for photonics applications.

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Searching for 3D effects in the optical, high spectral resolution emission spectrum of KELT-9b

10.5194/epsc2021-308 ◽

2021 ◽

Author(s):

Lorenzo Pino ◽

Matteo Brogi ◽

Jean-Michel Désert ◽

Emily Rauscher

Keyword(s):

Emission Spectrum ◽

Spectral Resolution ◽

Planet Formation ◽

Emission Spectra ◽

Optical Emission ◽

High Spectral Resolution ◽

Optical Emission Spectrum ◽

Hot Jupiters ◽

Atmospheric Structure ◽

3D Effects

<p>Ultra-hot Jupiters (UHJs; T<sub>eq</sub> &#8805; 2500 K) are the hottest gaseous giants known. They emerged as ideal laboratories to test theories of atmospheric structure and its link to planet formation. Indeed, because of their high temperatures, (1) they likely host atmospheres in chemical equilibrium and (2) clouds do not form in their day-side. Their continuum, which can be measured with space-facilities, can be mostly attributed to H- opacity, an indicator of metallicity. From the ground, the high spectral resolution emission spectra of UHJs contains thousands of lines of refractory (Fe, Ti, TiO, &#8230;) and volatile species (OH, CO, &#8230;), whose combined atmospheric abundances could track planet formation history in a unique way. In this talk, we take a deeper look to the optical emission spectrum of KELT-9b covering planetary phases 0.25 - 0.75 (i.e. between secondary eclipse and quadrature), and search for the effect of atmospheric dynamics and three-dimensionality of the planet atmosphere on the resolved line profiles, in the context of a consolidated statistical framework. We discuss the suitability of the traditionally adopted 1D models to interprete phase-resolved observations of ultra-hot Jupiters, and the potential of this kind of observations to probe their 3D atmospheric structure and dynamics. Ultimately, understanding which factors affect the line-shape in UHJs will also lead to more accurate and more precise abundance measurements, opening a new window on exoplanet formation and evolution.</p>

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Optical Emission Spectra of Oxygen Plasma Produced by Radio-Frequency Plasma

Applied Science and Convergence Technology ◽

10.5757/jkvs.2009.18.2.102 ◽

2009 ◽

Vol 18 (2) ◽

pp. 102-107

Author(s):

Do-Yeob Kim ◽

Min-Su Kim ◽

Tae-Hoon Kim ◽

Ghun-Sik Kim ◽

Hyun-Young Choi ◽

...

Keyword(s):

Radio Frequency ◽

Oxygen Plasma ◽

Emission Spectra ◽

Optical Emission ◽

Radio Frequency Plasma ◽

Frequency Plasma ◽

Optical Emission Spectra

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REFORMING OF ETHANOL IN PLASMA-CATALYTIC SYSTEM WITH DC AND AC ROTATING GLIDING DISCHARGE

10.46813/2021-131-117 ◽

2021 ◽

pp. 117-121

Author(s):

O.A. Nedybaliuk ◽

T.A. Tereshchenko ◽

I.I. Fedirchyk ◽

P.V. Tyshchuk ◽

V.P. Demchina

Keyword(s):

Synthesis Gas ◽

Emission Spectra ◽

Optical Emission ◽

Reaction Chamber ◽

Catalytic Reforming ◽

Instantaneous Power ◽

Wide Aperture ◽

Ethanol Reforming ◽

Gliding Discharge ◽

Optical Emission Spectra

The article presents the results of the investigation of the reforming of ethanol into synthesis gas using a plasmacatalytic system with either AC or DC wide-aperture rotating gliding discharge. Current and voltage oscillograms of the wide-aperture rotating gliding discharge were measured. The time-dependence of the instantaneous power of the discharge in the air was built. The photographs of the discharge in the airflow and discharge during the ethanol reforming were compared. The optical emission spectra of the plasmas of the torches of AC and DC wide-aperture rotating gliding discharges were studied. The rotational and vibrational temperatures of the plasma torch in the reaction chamber were determined. The results of the gas-chromatography of the synthesis gas produced during the plasm-catalytic reforming of ethanol using either AC or DC rotating gliding discharge are presented.

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