We confirmed the effect of organic material adhesion as ultrafine bubble (UFB) stabilization mechanism. Organic material was added to generate UFB, and the state of UFB particles was investigated by dynamic light scattering method, transmission electron microscope (TEM), resonance mass measurement method. Disappearance of UFB was suppressed by the addition of organic material, and it was confirmed that the organic material adhered to the surface of UFB. We got the conclusion that adhesion of organic material inhibit gas dissolution from bubbles.

The damage produced by focused ion beam (FIB) milling on a TEM sample of AlGaAs crystals has been studied. The damage observed on the sidewall of an AlGaAs transmission electron microscopy (TEM) sample was an amorphous layer. The thickness of the amorphous layer linearly increased with an increase in FIB accelerating voltage from 5 to 30 kV. The thickness of the amorphous layer of Al(x)Ga(1-x)As was constant at 3 nm and was independent of the Al concentration x when the accelerating voltage was below 5 kV. The thickness of the amorphous layer of Al(x)Ga(1-x)As decreased with an increase in Al concentration x when the accelerating voltage was above 5 kV. FIB milling at 5 kV effectively minimizes the thickness of the amorphous layer and also provides flat sidewalls on multilayer samples of Al(x)Ga(1-x)As that are prepared for TEM and scanning electron microscopy (SEM).

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A novel and practical method is proposed for the detection of gaseous OH radicals using a moisture‐resistant organic salt composed of terephthalic acid (TPA) and n‐alkylamine. When the alkyl chain length was greater than 8, the organic salt had a crystal structure in which the alkyl chains were arranged parallel to each other and zero‐dimensional voids were adjacent to terephthalate (TA). Since the parallelly arranged alkyl chains acted as a hydrophobic block, the organic salts had excellent humidity durability. The highly hydrophobic bis(n‐octylammonium) terephthalate (nOA‐TA) powder was exposed to gaseous OH radicals generated by a low‐pressure mercury lamp and a fluorescence response suggesting the formation of bis(n‐octylammonium) hydroxyterephthalate (nOA‐HTA) was observed. The presence of the zero‐dimensional voids in the nOA‐TA crystal caused the formation of nOA‐HTA. In addition, a sheet was prepared in which nOA‐TA crystals were uniformly immobilized in the pores of a membrane filter, and the spatial distribution of OH radicals was evaluated.

Lateral and depth profiles of the ion-implanted region were first observed using cleaved cross-sectional scanning electron microscope. The amorphous region induced by ion bombardment appears dark relative to the crystalline region. It is found that the secondary electrons, as well as the backscattered ones, are influenced by the so-called channeling effect.