Sigma 500 vp fe sem

Whole-bone biomechanical properties were measured in femurs isolated from 2-month-old and 4-month-old wild-type and MMP13^ocy−/− mice. Whole hydrated femurs were loaded to failure in three-point bending using a Bose Electroforce 3200 test frame. One femur per mouse was broken in the direction of primary physiological bending (posterior compression), and the other was broken against the direction of physiological bending (anterior compression). An 8-mm span was chosen because it was approximately 50% of the bone length. Tests were performed in air at a fixed displacement rate of 10 μm‧S⁻¹. Whole-bone stiffness was calculated from the linear portion of the load-displacement curve, and yield was designated as the point where a line representing a 10% loss in stiffness intersected the load-displacement curve.^{80 (link)} Following fracture, bone cross-sections were imaged by scanning electron microscopy on a Sigma 500 VP FE-SEM (Zeiss) at an excitation voltage of 15 kV and a partial pressure of 35 Pa. Measurements of cross-sectional diameter and thickness were acquired in ImageJ and used to calculate moment of inertia assuming an elliptical cross-section. These geometric parameters were used to convert the load-displacement data to stress–strain data in order to measure tissue modulus, tissue stress, and tissue strain with standard beam theory equations.^{81 (link)}

All prepared PVA/MZFA nanocomposite films were characterized using X-ray diffraction (XRD). The patterns were determined using a Shimadzu 600—0XRD X-ray diffractometer using Cu-Kα radiation (λ = 1.54056Å). The pure ferrite sample morphology was investigated using scanning electron microscopy (SEM) (ZEISS Sigma 500 VP FE-SEM), equipped with a secondary electron detector and EDX to quantify the presented elements. Fourier transform infrared (FTIR) spectroscopy was performed using Perkin-Elmer-1430 at room temperature in the range of 200 to 4000 cm⁻¹. The microstructure, surface roughness, adhesion force, friction coefficient, and specific surface energy were determined using a multifunctional atomic force microscope (AFM).

For scanning electron microscopy, cells mounted on coverslips were fixed gradually with 0.1–1.0% glutaraldehyde in 0.1 M phosphate buffer pH 7.4 at room temperature for 1 h. Samples were post-fixed with 1% Osmiumtetroxid for 1 h at room temperature and then dehydrated in graded ethanol series (30–96 and 100% (vol/vol) EtOH). Critical point drying (Baltec CPD) and sputter coating (Baltec Sputter Coater 500) was applied. In addition, coverslips were placed on stubs covered with a conductive double-coated carbon tape. Images were acquired with a Sigma 500VP FE-SEM with a SEM Detector (Zeiss Oberkochen) operated at an acceleration voltage of 3 kV.