Ols4000

The roughness of rectangular specimens was evaluated with a rugosimeter (Surftest SJ-201P; Mitutoyo, Tokyo, Japan) (n=20) and a 3D laser confocal microscope (OLS4000; Olympus Tokyo, Japan) (n=3). Using the rugosimeter, three readings were performed (4 mm in length) for each specimen, and the cut-off value was 0.8 mm at a speed of 0.5 mm/s. The roughness of each specimen was calculated by the arithmetic mean of three measurements (μm). Values within 0.20 µm were considered clinically acceptable.^{17 (link),21 (link)} For analysis under the 3D laser confocal microscope, the specimens were placed in a parallel position and 3 random images were captured. The images were obtained with a 5× objective, at a final magnification of 108×, and the mean roughness of each image (Sa) was calculated.

For imaging of the topography and measuring the roughness of the surfaces, a confocal laser scanning microscope (CLSM) LEXT OLS 4000 and the software OLS4000 (Version 2.2.3, 2012, Olympus, Hamburg, Germany) were used. The average area surface roughness Sa was determined ten times at random areas for reference and structured sample, respectively. An optical magnification of 50× was used, leading to a scan area of 256 × 256 µm. A scanning electron microscope (SEM) Merlin VP compact (Carl Zeiss AG, Jena, Germany) was used to take high-resolution figures of the reference and structured surfaces.

Surface chemical characterizations of the neat and modified polymer membranes were investigated by FTIR/ATR (TENSOR 27, Broker, Germany). A scanning electron microscope (SEM, S-4800, Hitachi, Japan) was employed to observe the morphologies of the membranes. A three-dimenstional (3D) measuring laser microscope (LEXT, OLS4000, Olympus, Japan) was employed to acquire the soiled surface morphologies of the membranes after UF experiments. The mechanical properties of the membranes were evaluated with a tensile testing equipment (AGS-J, China). The static and dynamic water contact angles (WCAs) were measured by a DropMeter contact angle measuring system (DSA100, Kruss, Hamburg, Germany) at room temperature. A UV–VIS spectrophotometer (TU-1901, Pgeneral, Beijing, China) was applied to determine the absorbance of feed and permeate solutions.

Within the profilometry study, we verified the roughness and thickness of electrospun samples using laser microscopy (Olympus OLS4000, Tokyo, Japan), from a larger area [56 (link)] than usually is reached with AFM [57 (link)]. The measured area for all samples was 646 × 646 μm, except PA6, where it was 130 × 130 μm due to smaller fiber diameter. We obtained roughness average (R_a), which is used to describe the roughness of measured surfaces, calculated with the digital approximation of:
$R_{\mathrm{a}}=\frac{1}{\mathrm{MN}}{\displaystyle \sum _{\mathrm{j}=1}^{\mathrm{M}}}{\displaystyle \sum _{\mathrm{i}=1}^{\mathrm{N}}}\left|{\mathrm{Z}}_{\mathrm{ij}}\right|$
where M and N is a number of data points in X, Y direction, and Z is the surface height relative to the reference mean plate. The 2D images from profilometry analysis of all electrospun samples and thickness measurements are provided in the Supporting Information, Figure S2.

The morphologies of the worn surfaces were determined by Zeiss AURIGA FESEM. The wear depth and wear track profiles after the friction tests were obtained by a noncontact 3D surface profiler (Olympus OLS4000), and the wear volume of the plates was calculated from the wear depth. The final values quoted for the wear volume of the specimen were averages of three tests results. The chemical compositions of the worn surfaces were characterized by a VG model Escalab 250 X-ray photoelectron spectroscopy (XPS) with Al-Kα radiation as the excitation source. And the binding energy of C1s at 284.6 eV was utilized as the reference. Prior to the analysis, the specimens were cleaned ultrasonically for 5 min with acetone, in order to eliminate the residual lubricant.

Surface structure and quality of diamond films were characterized by laser confocal microscopy (Olympus, OLS4000, Tokyo, Japan), scanning electron microscopy (SEM, LEO4500, Jena, Germany), and Raman spectroscopy. Raman spectroscopy was carried out using a Horiba HR-800 Raman spectrometer (Paris, France) with a 532-nm wavelength laser at room temperature. The in-plane thermal conductivity of samples was measured using the photothermal deflection technique, as described in detail in the literature [37 (link)]. The permittivity of the samples was measured using the transmission/reflection (T/R) technique using an Agilent N5244A vector network analyzer (Palo Alto, CA, USA) [38 (link)].
The device used for the T/R measurement is schematically shown in Figure 2a. The device measures the reflection and transmission of a microwave reference signal when it passes through the material in a waveguide. In the T/R measurement of this study, the surfaces of all samples were ablated by laser faced to the incident wave, as shown in Figure 2a. In Figure 2b, a practical measurement system is shown.

Micro-computed tomography (Micro-CT, Y.Cheetah, YXLON, Hamburg, Germany) was used to measure the internal structures of the pure PEEK and PEEK/CS composite scaffolds. The surface morphologies of the scaffolds were characterized via scanning electron microscopy (SEM, su-8010, Hitachi, Japan) after being coated with Au. The acceleration voltage and electric current was set as 10 kV and 20 μA, respectively. Laser scanning confocal microscopy (LSCM, OLS4000, Olympus, Japan) was used to evaluate the surface roughness (Ra). The porosity of scaffolds with different CS content was further calculated based on weighting method.