Raman microscope

Morphological analysis was carried out on a SUPRA 55vp ZEISS field emission scanning electron microscopy (Oberkochen, Germany), while element mapping were obtained using a corresponding energy dispersive X-ray (EDX) spectra. Elemental analysis was carried out on Elementar vario MICRO cube elemental analyzer (Frankfurt, Germany). Carbon, hydrogen, nitrogen, and sulfur content (% CHNS) was determined by combustible analysis using a thermal conductivity detector. Differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), and derivative thermogravimetry (DTG) were heated under nitrogen to 800 °C at a heating rate of 10 °C min⁻¹ using a simultaneous thermal analyzer Setaram Labsys Evolution (Lyons, France). Fourier-transform infrared spectroscopy (FT-IR) was performed using a Bruker VERTEX-70 FT-IR spectroscopy (Ettlingen, Germany), between 650 cm⁻¹ to 4000 cm⁻¹. Raman spectra was acquired using a Horiba Scientific Raman microscope (Paris, France) at an excitation laser wavelength of 532 nm with a 50X objective.

After the three-point bending test, the broken left femurs were collected. A segment of cortical bone of the femur along the horizontal plane was excised. After alcohol dehydration, the embedding process in epoxy resin and grinding, the samples for Raman spectroscopy (RS) were obtained. A Raman microscope (Horiba LabRAM, France) with a 785-nm wavelength laser source was adopted to obtain the spectra of femur cortical tissue. The laser was focused on a cross section of the femur cortex with a 50× magnification objective. The average of spectra obtained from three different sites of the femur cortex were employed to reflect the composition of the bone matrix. Curve fitting of Raman spectra was performed with Origin analysis software (OriginLab, USA), and the band area was calculated. The definition and calculation of the main Raman spectra-based compositional parameters in this study are described below: mineral-to-matrix ratio (area of v₁PO₄³⁻ [960 cm⁻¹] band: area of Amide I [1660 cm⁻¹] band), carbonate to phosphate ratio (area of v₁CO₃²⁻ [1060 cm⁻¹] band: area of v₁PO₄³⁻ [960 cm⁻¹] band), mineral crystallinity (inverse of v₁PO₄³⁻ [960 cm⁻¹] band width at half-maximum intensity).

The sulfate content of the ultrapurified sulfated fucan Fuc1 was externally analyzed using an Agilent 7500 Series quadrupole ICP-MS. The sulfate content of the hydrolyzed sulfated fucans was analyzed by Raman spectroscopy as previously described [12 (link)]. Raman spectra were recorded at room temperature using a Horiba Jobin–Yvon LabRAM HR system equipped with a Raman microscope (HORIBA Ltd., Kyoto, Japan).

Distilled H₂O mixed with specific wt% of CH₃OH was loaded, together with a ruby ball, into a symmetric diamond-anvil cell (DAC) with a culet size of 500 μm. The mixture itself served as a pressure transmitting medium. The pressure was determined by ruby fluorescence43 and the uncertainties of the pressure measurements were typically ~0.1 GPa. The compression and decompression rates of the samples were typically ~0.1 GPa s⁻¹. After the pressure within the DAC equilibrated and reached a stable value, the high pressure Raman spectra of H₂O-CH₃OH mixtures were measured at room temperature using a Raman microscope (Horiba Jobin Yvon) that employs a CW 514.5 nm Ar-ion laser to excite the mixture within the DAC and probes the Raman scattering and vibrational frequency shifts with a spectral resolution of ~2 cm⁻¹.

The cross-section of the film was observed using a Zeiss high-resolution field emission scanning electron microscope to explore the interface bonding ability of the three layers. Raman spectra of CNT-PDMS and pure PDMS films were obtained using a HORIBA Raman microscope with an excitation wavelength of 532 nm. The near-infrared light source used was a semiconductor laser integrated light source with a wavelength of 808 nm provided by Hite Optoelectronics Co., Ltd. (Beijing, China), and its power density was measured by a TP100 optical power meter. The surface temperature distribution and maximum temperature of the composite were measured and recorded by a T650sc infrared imager and paperless recorder. The bending deformation behavior of the film was recorded using an industrial camera, and the bending performance of the film was analyzed using the curvature calculation formula. The thermal expansion coefficient (CTE), thermal conductivity coefficient, and elastic modulus of each single layer film were measured by a thermomechanical analyzer (TMA), thermal conductivity meter, and intelligent electronic tension machine, respectively.