Microstructure of water sediments on hydrophilic surfaces

TL;DR

This study investigates the microstructure and phase transitions of water interacting with hydrophilic glass surfaces during drying, revealing complex behaviors of microdispersed phases and crystallization processes.

Contribution

The paper provides new insights into water microstructure and phase transitions on hydrophilic surfaces using optical microscopy, highlighting dynamic interactions during drying.

Findings

Observation of cascade phase transitions in water on glass surfaces

Identification of sodium chloride microcrystals surrounded by hydrate liquid crystal water

Documentation of microdispersed phase adhesion and recrystallization during evaporation

Abstract

In the modern world, the focus of natural science research thought has shifted mainly to the molecular level, including the study of water. Water is considered as a mixture of interacting H2O molecules and their clusters based on the data of molecular dynamics, neutron and X-ray scattering. In this case, a huge layer of information is lost related to the composition of real water, its microstructure and behavior. In this work, we studied the structure and dynamics of water during its interaction with glass surfaces during drying using optical microscopy. We observed a panoramic picture of a cascade of interrelated phase transitions of distilled water and its microdispersed phase - sodium chloride microcrystals surrounded by a thick layer of hydrate liquid crystal water. Incubation of a glass slide in water for 2 days was accompanied by adhesion of the microdisperse phase to the glass surface. During the free evaporation of distilled water from a Petri dish, erosion of hydration shells, dissolution of NaCl microcrystals, and further recrystallization with the formation of large monolithic crystals and traces of non-drying water were observed. However, there are still questions that do not yet have clear answers. The authors hope to continue research in collaboration with interested colleagues.