为提高颗粒药肥中除草剂的释放性能,制备了具有泡腾特性的除草药肥颗粒,以亚甲基蓝比色法评价其泡腾特性,研究了除草药肥颗粒中苯噻酰草胺和苄嘧磺隆的释放过程.结果表明,颗粒药肥具有显著的泡腾作用,苯噻酰草胺和苄嘧磺隆释放平衡时间为15和11min,仅为传统型颗粒药肥的33.3%和36.7%.两种除草剂的释放过程均遵循双常数方程和Logistic方程,且相关性达到极显著水平(P<0.001),释放速率由液膜扩散和颗粒内扩散联合控制.

The fertilizer-herbicide granule with effervescent agent coating was prepared to increase the herbicide release rate. The effervescency of the granule enjoys a remarkable performance, which was evaluated with the methylene blue spectrophotometric method. The experiments revealed the release kinetics of mefenacet and bensulfuron-methyl (BSM) in the granule. The results show that the release equilibration time of mefenacet and bensulfuron-methyl in the effervescent granule is 15 and 11min, respectively, 33.3% and 36.7% of that in the common fertilizer-herbicide granule. The release kinetics of mefenacet and bensulfuron-methyl follows the dual constant equation and Logistic equation, with a correlation coefficients highly significant (P< 0.001). Their release rates are controlled by the Boyd film diffusion model and the Kannan-Sundaram intraparticle diffusion one.