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Perilla frutescens leaves are hypothesized to possess antioxidant and amyloid-β (Aβ) aggregation inhibitory properties primarily due to their polyphenol-type compounds. While these bioactivities fluctuate daily, the traditional methods for quantifying constituent contents and functional properties are both laborious and impractical for immediate field assessments. To address this limitation, the present study introduces an expedient approach for on-site analysis, employing fluorescence spectra obtained through excitation light irradiation of perilla leaves. Standard analytical techniques were employed to evaluate various constituent contents (chlorophyl (Chl), total polyphenol content (TPC), total flavonoid content (TFC), and rosmarinic acid (RA)) and functional attributes (DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and Aβ aggregation inhibitory activity). Correlations between the fluorescence spectra and these parameters were examined using normalized difference spectral index (NDSI), ratio spectral index (RSI), and difference spectral index (DSI) analyses. The resulting predictive model exhibited a high coefficient of determination, with R2 values equal to or greater than 0.57 for constituent contents and 0.49 for functional properties. This approach facilitates the convenient, simultaneous, and nondestructive monitoring of both the chemical constituents and the functional capabilities of perilla leaves, thereby simplifying the determination of optimal harvest times. The model derived from this method holds promise for real-time assessments, indicating its potential for the simultaneous evaluation of both constituents and functionalities in perilla leaves.

Plasma enhanced chemical vapor deposition (PECVD) of silicon oxide (SiO2) using tetraethoxysilane (TEOS) was investigated theoretically by developing an unprecedented plasma chemistry model in TEOS/O2/Ar/He gas mixture. In the gas phase reactions, a TEOS molecule is decomposed by the electron impact reaction and/or chemically oxidative reaction, forming intermediate TEOS fragments, i.e., silicon complexes. In this study, we assume that SiO is the main precursor that contributes to SiO2 film growth under a particular process or simulation condition. The surface reaction was also investigated using quantum mechanical simulations with density functional theory. Based on the gas and surface reaction models, we constructed a computational plasma model for SiO2 film deposition in a PECVD process. The simulation results using CHEMKIN pro and CFD-ACE + have shown that the neutral atomic O and SiO as well as the charged O2+ are the dominant species to obtain a high deposition rate and uniformity. The spatial distributions of various species in the TEOS/O2/Ar/He gas mixture plasma were shown in the study. The uniformity of deposited film due to the change in the plasma bulk property was also discussed. [ABSTRACT FROM AUTHOR]

A reliable set of electron collision cross sections for water vapor, including elastic, rotational, vibrational, and electronic excitation, electron attachment, and ionization cross sections, is estimated by the electron swarm method. In addition, anisotropic electron scattering for elastic and rotational excitation collisions is considered in the cross section set. Electron transport coefficients such as electron drift velocity, longitudinal diffusion coefficient, and effective ionization coefficient are calculated from the cross section set by Monte Carlo simulation in a wide range of E/N values, where E and N are the applied electric field and the number density of H2O molecules, respectively. The calculated transport coefficients are in good agreement with those measured. The obtained results confirm that the anisotropic electron scattering is important for the calculation at low E/N values. Furthermore, the cross section set assuming the isotropic electron scattering is proposed for practical use. [ABSTRACT FROM AUTHOR]

A set of electron collision cross sections for trifluoromethane (CHF3) is estimated by the electron swarm method. Electron transport coefficients in CHF3, such as the electron drift velocity, longitudinal diffusion coefficient, and effective ionisation coefficient, are calculated from the estimated cross section set by the Monte Carlo method, and the values are compared with the measured data. In the case of the transport coefficients, good agreement is obtained between the calculated and measured values in a wide range of reduced electric fields. Furthermore, the transport coefficients described above and the characteristic energy in CHF3–Ar mixtures are calculated, and the values are found to agree well with the measured data. This confirms the validity of the cross section set for CHF3 estimated here. [ABSTRACT FROM AUTHOR]