Jsm 6490lv

The surface morphology of the developed micelles was analyzed using scanning electron microscopy (Cryo-SEM). Lyophilized OA-g-CS-PEN-MAN conjugate was used for the analysis. Briefly, the sample was mounted on conductive tape on a brass stub and gently tapped. The excess sample was blown out by implying airflow. The sample-mounted brass stub was visualized using JEOL JSM-6490LV (JEOL USA, Inc., Peabody, MA, USA) under a low vacuum with a laser beam (15 kV acceleration voltage) at 1500× magnification [45 (link),46 (link)]. Selected area electron diffraction (SAED) was also performed to evaluate the non-crystalline phase of the synthesized OA-g-CS-PEN-MAN conjugate. The SAED is a technique to acquire a 2-D electron diffraction pattern to differentiate between crystalline and non-crystalline samples.

A Scanning Electron Microscope (SEM) JEOL-JSM 6490LV was used for the study the presence and distribution of the AgNPs on the composite. Liquid nitrogen were used to freeze the samples and the fracture surfaces were observed. The composite with the highest concentration of AgNPs were also subjected to an energy dispersive X-ray analisis (EDX) accessory [34 ].

SEM microscope JEOL JSM-6490LV (JEOL, Peabody, MA, USA) operated in the low-vacuum mode was used to examine the CCB fractured surface after the flexural test. The samples were cut in small pieces and attached on a carbon adhesive after being covered with a gold film to make them conductive. The analysis conditions were similar to those described in Section 2.4.

SEM images of printed samples were taken using a Low Vacuum Scanning Electron Microscope (LVSEM) JEOL JSM-6490LV (JEOL, Peabody, MA 01960, USA) operating in high vacuum mode. The samples were coated with 15 nm of platinum (Pt) using a Dynavac SC100MS magnetron sputter coating system (Ezzi Vision Pty Ltd., Perth, Australia). Secondary electron imaging was performed at 15 kV accelerating voltage with a probe current setting of 45 and the specimen at 20 mm working distance. Images were taken at random cross sections of the scaffolds to better image layer resolution and filament shape. Magnifications of 250×, 1500× and 2500× were taken. For degradation samples, images were taken at random locations from a top-down view at 48 h and 96 h with magnifications of 100×. A high magnification of 0.5 wt.% graphene composite at 500× and 1000× was also imaged to determine the mode of degradation.

The formation of the biofilm was made in 1 cm × 1 cm glass coverslips using an inoculum of K. pneumoniae in saline solution at OD_600nm 0.05 in liquid LB medium containing the biofilm-inhibitors compounds. Thus, coverslips were incubated at 37 °C for 30 h. The fixation and drying of the material were done by heating at 37 °C for 12 h and then coated with a micronized gold microlayer. Finally, the biofilm was analyzed by Scanning Electronic Microscope, SEM (JEOL-JSM 6490LV, Peabody, MA, USA) operated at 20 kV, with 200X and 7000X of magnification.

The coating thickness was measured by DeFelsko Positector 6000 eddy current gauge with an N-type sensor. In addition, cross-section images were analysed. The top view of the PEO coating was studied using JEOL JSM-6490LV scanning electron microscope (SEM) (JEOL, Tokyo, Japan) and by Hitachi Regulus 8220 SEM (Hitachi, Tokyo, Japan). The coating elemental composition was determined using INCAX attachment of JEOL JSM-6490LV by the EDS analysis method.
The surface roughness was measured with the TR-220 profilometer (TIME Group Inc, Beijing, China). The coating porosity was assessed with Image J software from the SEM images following the ASTM E112-10.
The phase composition of the surface layer was characterized by X-ray diffractometer Rigaku Ultima IV (Rigaku, Tokyo, Japan) in CuKα radiation at 40 kV and 40 mA using 0.02 deg. step scan with 2 s exposure, from 25 to 80 degrees 2θ. Further, the XRD spectra were processed using X’Pert Highscore Plus 3.0 (PANalytical B.V., Almelo, The Netherlands) software with PDF2 pattern database; a built-in SemiQuant algorithm was employed to quantify the amounts of the crystalline phases in the coating.
The tribological properties were tested by a pin-on-disc Nanovea TRB-1 tribometer (Nanovea, Inc., Irvine, CA, USA) at a normal load of 2 N against a 6 mm diameter Al₂O₃ ball at a room temperature. The sliding speed was 0.1 m/s for a distance of 200 m.

Due to the fact that it was not easy to handle bacterial pellicles without damaging them, different methods were tested, and the use of activated carbon cloth (Kynol activated carbon clothes ACC 507‐20) was chosen as the best sampling method. Carbon cloth discs of 1 cm diameter were thoroughly washed with deionized water, autoclaved (at 120°C 20 min) and then used to harvest the pellicles by touching them with the activated carbon cloth. The discs were dried on a filter paper for 15 min and fixed by immersing them in methanol for 20 min, which was later replaced with absolute ethanol, which was renewed every 30 min for three times. Bacteria were then critical point dried, sputtered with gold and observed in a SEM Jeol JSM‐6490LV (Jeol, Akishima, Japan).