The optical characteristics of (PMMA/PVA) thin films are investigated by spectrometric measurements. Sample with different percentage are prepared with constant thickness (110 m) using casting technique. The real (n) and imaginary (k) parts of refractive index and dielectric constant of the thin films are determined. Some important parameters of optical absorption, such as the oscillator energy (E0), dispersion energy (Ed), the average value of oscillator strength (S0), wavelength (0) of single oscillator and the ratio carrier concentration to the effective mass (N/m*) have been evaluated. The values obtained for the high frequency dielectric constant through two procedures are in the range of (6.31-7.35) for all ranges of the different concentrations.

Silver-Poly vinyl alcohol Ag/ PVA nanocomposite films were prepared by casting method at room temperature with different amount of AgNO 3 solution (0.001, 0.0015, and 0.002ml). The prepared nanocomposites were characterized using UV-VIS spectrophotometer and the optical properties were investigated in the wavelength range 300-800 nm. The absorption peaks showed a shift towards higher wavelength with increasing AgNO 3 concentration while the energy band gap and absorption edges shifted towards lower energies with the increase of AgNO 3 concentration.

The effect of continuous CO2laser radiation on the optical properties of pure polyvinyl chloride and doped of ZnO nanoparticles with two different concentrations (10, 15%) has been investigated. All samples were prepared using casting method at room temperature. Optical properties (absorption, transmission, absorption coefficient, extinction coefficient, refractive index, and optical conductivity) of all films after CO2laser irradiated have been studied as a function of the wavelength in the range (200–800) nm for three energies (300, 400 and 500 mJ). It has been found that the transmission, energy gap, and refractive index increase with increasing laser energy. The values of absorption, Urbach energy, absorption coefficient, extinction coefficient, and optical conductivity were decreased.

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In this work, laser-induced breakdown spectroscopy (LIBS) analysis is optimized for direct estimation of elemental composition, thermal conductivity and hardness for Ni-Cr-Nb alloys. These alloys were chosen with a variable elemental content of niobium and chromium. The influence of laser energy and shot numbers on measuring line intensity was investigated. Based on the ratio between two spectral lines, calibration curves were formed to estimate the element concentration and LIBS results were confirmed with related energy-dispersive X-ray spectroscopy (EDS) data. Hardness and thermal conductivity estimation using LIBS were done by measuring the ratio between two spectral lines, plasma excitation temperature and electron density for different samples. Semi-empirical formulas correlated hardness and thermal conductivity with plasma temperature were established.