School of Food Science and Nutrition, The University of Leeds, Leeds LS2 9JT, United Kingdom.
Lewtas Science and Technologies, Ltd., 264 Banbury Road, Oxford OX2 7DY, United Kingdom.
J Chem Phys. 2023 May 7;158(17). doi: 10.1063/5.0139811.
We outline techniques for the control and measurement of the nucleation of crystalline materials. Small angle x-ray scattering/wide angle x-ray scattering x-ray diffraction measurements are presented that demonstrate the impact of low power, continuous, non-cavitational ultrasound on the nucleation and crystallization of a wax-n-eicosane dissolved in a heptane/toluene solvent. A mathematical-physical approach based on the rectification of heat and mass transport by such a low power oscillating pressure field is outlined, and it is suggested that this approach be combined with dissipative particle dynamics computational modeling to develop a predictive method capable of modeling the impact of low power oscillating pressure fields (acoustics and ultrasonics) on a wide range of nucleating systems. Combining the ultrasound pitch and catch speed of sound measurements with low power harmonically oscillating pressure fields to monitor and control nucleation presents the prospect of entirely new industrially significant methods of process control in crystallization. It also offers new insights into nucleation processes in general. However, for the acoustic control technique to be widely applied , further theoretical and modeling work will be necessary since, at present, we are unable to predict the precise effect of low power ultrasound in any given situation.
我们概述了控制和测量晶体材料成核的技术。介绍了小角 X 射线散射/广角 X 射线衍射测量，证明了低功率、连续、非空化超声对溶解在庚烷/甲苯溶剂中的蜡-二十烷的成核和结晶的影响。概述了一种基于这种低功率振荡压力场对热和物质传输整流的数理方法，并建议将该方法与耗散粒子动力学计算建模相结合，以开发一种能够模拟低功率振荡压力场（声学和超声）对广泛成核系统的影响的预测方法。将超声的频散和声速测量与低功率谐波振荡压力场相结合，以监测和控制成核，为结晶过程的控制提供了全新的、具有重要工业意义的方法。这也为一般成核过程提供了新的见解。然而，为了广泛应用声学控制技术，还需要进一步的理论和建模工作，因为目前我们无法在任何给定情况下预测低功率超声的确切效果。
