Ozone saturation and decomposition kinetics in porous medium containing different hybrids of maize

ABSTRACT The objective of this study was to evaluate ozone saturation and decomposition kinetics in porous medium containing grains of different hybrids of maize. The following hybrids were used: common maize hybrid AG 1051, super sweet maize hybrids Tropical Plus, GSS 42072, GSS 41499 and GSS 41243. 1 kg grain samples with water contents of 13.0% (w.b.) were placed in glass containers with 3.25 L capacity. The grains were ozonized at the concentration of 1.28 mg L-1, at 25 ºC, with gas flow rate of 5.0 L min-1. Saturation time and concentration, half-life time and physical properties such as apparent specific weight, actual specific weight, porosity, sphericity and circularity of each maize hybrid were determined. The experiments were conducted in a completely randomized design with three replicates, using regression analysis of the data. Ozone saturation times remained between 6.6 and 163.9 min, with saturation concentration varying from 0.34 to 1.12 mg L-1. As for the ozone half-life time, the highest value was 10.5 min for the common maize hybrid AG 1051 and the lowest value was 0.14 min for the super sweet maize hybrid GSS 41499. It was concluded that ozone saturation and decomposition kinetics in maize depends on the hybrid contained in the porous medium. Ozone decomposition is faster in porous medium containing super sweet maize hybrids compared with the common maize hybrid.

摘要 本研究旨在评估含不同玉米品种籽粒的多孔介质内的臭氧饱和特性与分解动力学特性。本研究选用的玉米品种包括：普通玉米品种AG 1051，以及超甜玉米品种Tropical Plus、GSS 42072、GSS 41499与GSS 41243。称取水分含量为13.0%（湿基，w.b.）的1 kg籽粒样品，置于容量为3.25 L的玻璃容器中。于25 ℃、气体流速5.0 L·min⁻¹的条件下，以1.28 mg·L⁻¹的臭氧浓度对籽粒进行臭氧处理。测定各玉米品种的臭氧饱和时间与饱和浓度、半衰期，以及表观比重、真比重、孔隙率、球形度与圆形度等物理特性。本实验采用完全随机设计，设置3次重复，并对数据进行回归分析。臭氧饱和时间介于6.6~163.9 min之间，饱和浓度范围为0.34~1.12 mg·L⁻¹。就臭氧半衰期而言，普通玉米品种AG 1051的半衰期最长，为10.5 min；超甜玉米品种GSS 41499的半衰期最短，仅为0.14 min。本研究得出结论：玉米多孔介质内的臭氧饱和与分解动力学特性取决于所采用的玉米品种；相较于普通玉米品种，含有超甜玉米品种的多孔介质内臭氧分解速率更快。