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Objective: Establish a computer model for predicting the inactivation of Zygosaccharomyces rouxii in apple juice by surface discharge plasma (SDP). Methods: The numerical simulation software COMSOL multiphysics was used to model SDP inactivation of Z. rouxii LB. The inactivation efficiency was evaluated under different conditions of discharge voltage, bubble size and sample volume. The model was then validated. Results: SDP was highly effective in deactivating hyperosmotic-resistant yeast in apple juice. The reaction rate coefficient decreased with an increase in the initial concentration of bacteria. Furthermore, the increase in discharge voltage shortened the time needed to inactivate yeasts. Bubble size variations had no significant effect on the inactivation of Z. rouxii LB, and the inactivation time was prolonged with increasing sample volume. The model simulation results agreed with the experimental data.

In this study, the effect of ochratoxin A (OTA) concentration and discharge voltage on the degradation of OTA in artificially contaminated raisins by low-temperature discharge plasma was explore. The results indicated that OTA in raisins contaminated with 50 μg/mL OTA was completely degraded by plasma treatment for 10 minutes at a discharge voltage of 75 kV. The degraded products of OTA were detected by high performance liquid chromatography-quadruple-electrostatic field orbitrap high resolution mass spectrometry. Based on the primary and secondary mass spectra, two major degraded products with m/z 426.071 5 (B) and m/z 158.154 0 (C) and the possible degradation pathway of OTA were speculated. There was no significant change in the physicochemical quality of raisins before and after plasma treatment, and the relative contents of most acids, aldehydes, alcohols and ketones did not significantly change, except for a significant decrease in the contents of 3-methylbutyric acid, acetic acid and caprylic acid among acids, and a significant increase in the contents of formic acid, valeric acid, and 2-ethylhexanoic acid. The research results suggest that low temperature discharge plasma can effectively degrade OTA while having no significant effect on raisin quality, which can provide a reference for OTA degradation in contaminated foods.

The inactivation effect of plasma spray reactor on Zygosaccharomyces rouxii in apple juice was studied as a function of plasma discharge voltages, gas flow rate and liquid flow rate, and the morphological changes of the cells and the effect of this treatment on apple juice quality were evaluated. In this study, a plasma spray reactor was used to treat 0.5 L of apple juice for 30 min at a discharge voltage of 21 kV, a gas flow rate of 150 L/h, and a liquid flow rate of 9.0 L/h. The number of osmotolerant yeast cells in apple juice decreased significantly. Plasma spray reactor treatment caused cell rupture, thus resulting in the inactivation of yeast cells. Under the optimal parameters, this treatment increased the pH of apple juice slightly, but did not cause any significant changes in the titratable acid or reducing sugar concentration (P > 0.05) and resulted in no significant changes in the major major volatile compounds in apple juice. This study may provide a reference for the application of plasma spray reactor in apple juice processing.

In this article, the ultrafast tracking control for high-order discrete-time multiagent networks is investigated based on the predictive ability of agents. First, in view of the evolution of the original network dynamics, a distributed multistep prediction algorithm is established. Further, a control strategy containing predictive information is presented to achieve the ultrafast tracking control. Second, the problem of ultrafast tracking control with an $H_{\infty }$ performance specification is dealt with. The obtained result indicates that the robustness of the whole multiagent network can be converted into the robustness of multiple separable subsystems. Finally, the optimal ultrafast static tracking control design is provided for the single-integrator network with sampled dynamics. Two simulation cases are carried out to verify the correctness of the obtained theoretical results. [ABSTRACT FROM AUTHOR]

This paper studies the multi‐tracking control for high‐order heterogeneous multi‐agent systems under a directed acyclic graph. The authors first convert the multi‐tracking control problem for multi‐agent systems into the zero steady‐state error control problem of some independent subsystems. Based on final‐value theorem and Mason's rule, a sufficient condition for achieving the multi‐tracking control is proposed. It explicitly reveals how the system dynamic and desired object dynamic jointly affect the multi‐tracking control of heterogeneous multi‐agent systems. Meanwhile, a new result on the steady‐state error for multi‐subnetworks is established. Moreover, the multi‐tracking control for heterogeneous multi‐agent systems with time delay is discussed. Some simulations are performed to illustrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]