[Objectives] The paper was to explore whether the microemulsion is a nano-pesticide. [Methods] Several microemulsions commonly available on the market were studied from the perspective of particle size and morphologic...[Objectives] The paper was to explore whether the microemulsion is a nano-pesticide. [Methods] Several microemulsions commonly available on the market were studied from the perspective of particle size and morphological characteristics. With ZIF nano-pesticide prepared earlier as the control, the changes in particle size of microemulsions diluted at different concentrations and the microscopic morphology of dispersed particles were tested and compared by dynamic light scattering laser particle size analyzer combined with scanning electron microscope. [Results] Conventional microemulsions were in dynamic equilibrium, and the particle size changed irregularly after dilution at different concentrations. Especially under scanning electron microscope, the particle distribution of pesticide-bearing droplets were uneven after drying, with aggregation and precipitation of large particles, while the particle size of nano-pesticide changed little after dilution at different concentrations, ranging from 1 to 300 nm. Moreover, the microscopic morphology of nano-pesticide observed under scanning electron microscope was in monodisperse nano state, without aggregation. [Conclusions] The particle size measured by dynamic light scattering alone can not judge whether the microemulsion is a nanometer pesticide, and it is necessary to observe the microscopic disperse state and particle size distribution with the help of electron microscopy.展开更多
The relation between the critical radius and the particle size distribution for generalized Ostwald type ripening processes whereby the mass transfer coefficient is modelled by a power law was derived. The critical ra...The relation between the critical radius and the particle size distribution for generalized Ostwald type ripening processes whereby the mass transfer coefficient is modelled by a power law was derived. The critical radius is determined by the growth rate, the mass transfer coefficient and the mass balance, and is independent of whether the limiting stationary growth regime has been obtained.展开更多
基金Supported by Zhejiang Public Welfare Technology Application Research- Analysis and Test Project (LGC22C140001)Laboratory Work Research in Colleges and Universities of Zhejiang Province (ZD202104).
文摘[Objectives] The paper was to explore whether the microemulsion is a nano-pesticide. [Methods] Several microemulsions commonly available on the market were studied from the perspective of particle size and morphological characteristics. With ZIF nano-pesticide prepared earlier as the control, the changes in particle size of microemulsions diluted at different concentrations and the microscopic morphology of dispersed particles were tested and compared by dynamic light scattering laser particle size analyzer combined with scanning electron microscope. [Results] Conventional microemulsions were in dynamic equilibrium, and the particle size changed irregularly after dilution at different concentrations. Especially under scanning electron microscope, the particle distribution of pesticide-bearing droplets were uneven after drying, with aggregation and precipitation of large particles, while the particle size of nano-pesticide changed little after dilution at different concentrations, ranging from 1 to 300 nm. Moreover, the microscopic morphology of nano-pesticide observed under scanning electron microscope was in monodisperse nano state, without aggregation. [Conclusions] The particle size measured by dynamic light scattering alone can not judge whether the microemulsion is a nanometer pesticide, and it is necessary to observe the microscopic disperse state and particle size distribution with the help of electron microscopy.
基金Project (No. 20076039) supported by the National Science Founda-tion of China
文摘The relation between the critical radius and the particle size distribution for generalized Ostwald type ripening processes whereby the mass transfer coefficient is modelled by a power law was derived. The critical radius is determined by the growth rate, the mass transfer coefficient and the mass balance, and is independent of whether the limiting stationary growth regime has been obtained.
