Scanning electron microscope

SEM tests were carried out on 1 mm × 2 mm × 3 mm samples that were subjected to a salt-fog experiment with DC energized. The device was a scanning electron microscope manufactured by FEI, Hillsboro, USA with an adjustable magnification of 80–150,000.

Adult worms were handled using the methods outlined by Abou Rayia et al. [29 (link)]. A fresh fixation solution containing 2.5% glutaraldehyde solution buffered with 0.1 M sodium cacodylate at pH 7.2 was used to fix worms from each group immediately and kept overnight at 4 C. After that, the fixed specimens were washed in 0.1 M sodium cacodylate buffer at pH 7.2 for 5 min, post-fixed in 2% osmium tetroxide for 1 h, and rinsed in distilled water.
The samples were dehydrated in ethyl alcohol in increasing concentrations, mounted on adhesive material with a carbon coating, and analyzed by FEI-Philipps scanning electron microscope [42 (link), 43 (link)].

The MWCNTs used in this experiment were produced using the chemical vapor deposition method. There was a large van der Waals force between the MWCNTs. A high efficiency nonionic surfactant (90% active contents, 68–70 °C cloud point) purchased from Chengdu Organic Chemicals (Chengdu, China) Co. Ltd. was used in this experiment. Its structure consisted of a hydrophilic group and an aromatic ring, which could improve the dispersibility of the MWCNTs significantly. Based on previous studies [22 (link),23 (link),24 (link)], MWCNTs powder and surfactant were placed in water and stirred evenly. Then, an ultrasonic disrupter (20 kHz, 450 W) was employed to disperse MWCNTs in water for 30 min. Finally, dispersion was subjected to centrifugation (2000 rpm, 30 min) and filtration treatment.
The dispersion contained 2 wt.% MWCNTs, which were uniformly black in color, and little sedimentation occurred due to the van der Waals forces after 90 days of static settling. The highly concentrated MWCNT-bearing liquid was diluted with water. Drops of this solution were placed on a sample holder and observed using an environmental SEM (scanning electron microscope, FEI Company, Hillsboro, OR, USA), as shown in Figure 1. Some of the MWCNTs were shortened during the dispersion process, which mainly occurred due to the ultrasonic vibration.

The morphological analyses of the two materials were carried out using scanning electron microscopy. For this purpose, a scanning electron microscope purchased from the FEI Company (Hillsboro, OR, USA) was used. The samples were shaped with a diamond disc and fixed on a sample support to be introduced into the analysis zone. The shape and size of the PVA/CS nanofibers of the mesh were determined through micrographs of the samples by direct measurements of the resulting secondary electron beam with a 30 keV energy at different points of the samples.

A random sample from each of the study groups was selected for the studying resin-bracket interface and bacterial culture over the discs under a scanning electron microscope (FEI, Tokyo, Japan). The process of fixation of these specimens was done by using a combination of 4% paraformaldehyde and 2% glutaraldehyde in 0.1 M sodium cacodylate (NaCac) buffer solution. The pH for these samples was maintained at 7.4 and was allowed to be stored overnight. The specimens were then subjected to 2% osmium tetraoxide before undergoing dehydration via ethanol (50 to 100%). These dried discs were then taped with double-sided copper tape. 10 kV disc images were obtained with the help of a through-lens detector (TLD) for secondary electron imaging.

The microstructure of the gels was determined using a scanning electron microscope (FEI Company, Eindhoven, The Netherlands). The samples were mounted on bronze stubs and coated with gold to ensure electrical conductivity. The specimens were examined at an acceleration voltage of 15 kV.