Microscopic and macroscopic wettabilities of various silica surfaces loaded with trimethylsilyl groups were studied, focusing on the effect of the surface geometrical structures. The geometrical structures in micro and macro scales were investigated by water vapor adsorption. The microscopic wettability was determined by water vapor adsorption, while the macroscopic wettability was measured by the contact angle. The microscopic wettability affects the continuous two dimensional water layer. The macroscopic wettability influences the capillary condensation and surface roughness. The wettability of surface was essentially governed by the microscopic wettability, which is a primary property of various silica surfaces. The capillary condensation and surface roughness enhance wettability as a secondary effect which results from the primary property.

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Bakers' yeast cell was disrupted with a high-pressure homogenizer (Rannie: MIMI-LAB) without an impact ring to investigate the effect of number of pass time (i. e., disruption time) and applied pressure on the release performances of enzymes (Cu, Zn-SOD, Mn-SOD) and soluble proteins.
The release of enzymes and proteins was formulated with a disruption rate model by Hetherington et al. The intercellular materials were released from the deformed (i. e., partially disintegrated) cells caused by shear flow through small gap at a pressure lower than 40MPa, and the cells were completely disrupted at a pressure higher than 60MPa. The amount of intercellular materials released into the suspension increased linearly with the number of pass and they were correlated with the particle size of cell debris. Although a linear relationship between the released amount of materials and the particle size was obtained, a lower pressure gave a lager amount of released materials at the same particle size. The amount of released materials was also correlated with electric conductivity of suspension.

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Formation of particle deposition layer was investigated as a simultaneous phenomenon of particle deposition and reentrainment in a turbulent aerosol flow. Aerosol particles passed through a corona charger were pneumatically transported into a glass tube equipped with a ring-type electrode, and the deposition layers formed on the tube wall in various conditions were quantitatively analyzed with particular attention to the effects of particle charge and external electric field on the deposition layer. The charged particles formed a deposition layer of a filmy pattern around the electrode being independent of the polarity of particle charge and applied voltage. The mass of deposition layer increased with elapsed time and became constant after an equilibrium state of particle deposition and reentrainment. The time dependency was represented by an exponential equation; the time constant decreased with increasing particle charge and/or applied voltage, and the equilibrium mass of deposition layer increased with the particle charge. Furthermore, it was found that appropriate arrangement of electrodes to control external electric field eliminates the filmy pattern deposition layer.

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