Development of portable device for measuring accumulation rate of sea salt particles

We have developed a new portable device for measuring the accumulation rate of sea salt particles. This device is composed of two sets of handy QCM devices, a handy vacuum desiccator and a handy moistening. QCM sensor used was Ag-coated one with 30 MHz in resonant frequency. The resonant frequency change with the relative humidity was measured under different size and amount of attached sea salt particles. The result shows that the resonant frequency was decreased as the relative humidity increased. The decrease of resonant frequency was caused by the weight increase of MgCl2 solution in the sea salt particles. QCM sensor was exposed on outdoor and the amount of attached sea salt was estimated by the resonant frequency change with the relative humidity.