ABSTRACT
Pomegranate is a kind of fruit with low temperature sensitivity. Abnormal low temperature can easily lead to chilling injury, which negatively impacts the appearance of fruit, accelerates browning and deterioration, as well as seriously reduces the consumption quality and commodity value of pomegranate. This study was carried out to determine the effect of methyl jasmonate on chilling injury of pomegranate during low temperature storage. The result showed that methyl jasmonate treatment effectively maintained edible quality of pomegranate, suppressed the polyphenol oxidase activity and the development of chilling injury index, and inhibited the decline of total phenol content and the increase of malondialdehyde content and cell membrane permeability. In addition, methyl jasmonate could also enhance the disease resistance of fruit by increasing the content of soluble protein, and effectively maintain the integrity of epidermal cell structure and tissue structure. Overall, the conclusion of this paper is that methyl jasmonate can be used as an effective means to suppress chilling injury in postharvest storage of pomegranate.
Subject(s)
Acetates , Cyclopentanes , Food Storage , Fruit , Oxylipins , Pomegranate , Acetates/pharmacology , Cold Temperature , Cyclopentanes/pharmacology , Food Storage/methods , Fruit/drug effects , Fruit/standards , Oxylipins/pharmacology , Pomegranate/drug effectsABSTRACT
Hybrid laser double-arc welding is a complicated process with many random and uncertain influencing factors because of the interactions of energy, forces, and fields. The wire spacing is one of the main factors affecting the coupling behavior of laser and arc plasma and the stability of welding process. However, it is difficult to establish a precise mathematical model for evaluation of welding stability. In this paper, the largest Lyapunov exponent (LLE) of characteristic currents during the welding process under different wire-wire distances were numerically evaluated by the phase space reconstruction technique. Synchronous high-speed photography was adopted to observe arc shape and droplet transfer. The experimental and calculated results indicate that hybrid laser double-pulsed arc welding is a complex process of chaos. The LLE can provide a criterion for welding stability and can agree well with the observation of electrical signal, arc shape, and droplet transfer. Research results are needed to understand the welding process and to guarantee a stable and safe joining.
