The objectives of this study were to estimate the effect of the blue light cure unit on the compression force and hardness for composite resin nanoCeram at different thickness. The basic material used in this study was Ivoclar Vivadent Tetric N-Ceram Light Cured Hybrid restorative composite resin. The samples were cured by applying a (LED.F) unit Blue phase in a wavelength emission spectrum (494 NM) was used.60 disc-shaped specimens [9 mm diameter at (0.5, 1) mm thickness and 10 mm diameter at (1.5) mm thickness] were prepared using a stainless steel mold for hardness and compressive strength measurements. A composite resin was polymerized with an aid of a ( DC 5V/1A) lamp for (10, 20 and 30) sec .Three specimens were used for each group.The results were analyzed using (linear logarithmic, quadratic, linear and power) test.The different groups showed significant variability in relation, with a significant interaction between the groups.The result showed that the greater thickness more efficient for polymerization than small thickness and the long irradiation time more efficient for polymerization than short irradiation time, long irradiation time diffusion in deep portions of the sample convert to polymer and this provide good polymerization and then good mechanicalproperties.

Gallium arsenide (GaAs) nanoparticles' optical and emission properties can be tuned bychanging their size across the visible spectrum. GaAs nanoparticles' optical characteristics aredegraded by oxidation on their surface. This work investigated the optical constants and the opticalband gap for a GaAs nanoparticle immersed in acetone using the laser ablation into liquids (LAL)technique after being exposed to a Nd: YAG pulsed laser operating at the wavelength (1064nm)10Hz frequency, and 7ns pulse width for a fixed flounce of 1.32 J/cm2, and the time of ablationwas 5 minutes. In order to calculate the optical conductivity (σ), refractive index (n), extinctioncoefficient (k), dielectric constant, absorption coefficient (α), and optical band gap, an opticalinvestigation was carried out utilizing a UV-Visible Spectrophotometer region in the wavelengthrange 300-1200 nm. The band gap energy was determined to be 3.8 eV, which is greater than thebulk Ga energy. The band gap energy of nanoparticles increases with increasing laser pulse energyand decreases with increasing pulse repetition rate. Transmission spectra increased as wavelengthsincreased, while optical absorption coefficients, extinction coefficients, and refractive coefficientsdecreased. The difference in optical constants is explained by defect states and the average bandenergy of the system. The acetone stability test reveals a peak at -0.69 mV, indicating low stabilityin nanoparticles.

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The aim of this paper is to estimate the mean monthly values of wind power density in four meteorological stations in Nineveh Governorate (Mosul, Rabea, Talafar, Sinjar) for the period (1980 -2010) using different meteorological parameters. Five different models (Linear, Quadratic, Logarithmic, Linear Logarithmic, power) were used to estimate the wind power density. The performance of this regression models were evaluated. Several statistical test were used to control the validation and goodness of the regression models in terms of (R, R 2 , MAE, RMSE). Linear model gave the best fit for the relation between WPD and (P, n, H, C) in all stations. Quadratic model and Linear model gave the best fit between WPD and (Rad. RH, T) in all stations. Logarithmic model give the best fit between WPD and Rad in Mosul station.

The purpose of this study is to see how low-power red laser helium-neon and diode lasers with wavelengths of 632.8 nm and 650 nm, respectively, affect some human blood sample factors like viscosity HCT, Platelets PLT, White blood cells WBC, white blood lymphocytes LYM, neutrophilic white blood cells NEUT, red blood cells RBC, and Erythrocyte Sedimentation Rate ESR. Blood samples were collected from healthy people and placed in EDTA-contained tubes, blood tests were performed on control samples in a blood analyzer, and the samples were divided into two parts and split into two equal tubes to be irradiated with diode and helium-neon lasers for 15 minutes. Using a blood analyzer, measurements were taken immediately after irradiation. The results of this analysis indicated a decrease in the number of white blood cells (WBC), red blood cells (RBC), and blood viscosity (HCT), as well as a significant rise in the number of neutrophils (NEUT) and platelets (PLT) and increase in the Erythrocyte Sedimentation Rate ESR after exposure to both helium-neon and diode lasers. This suggests that It is possible to make recommendations, a low-power laser could be used to stimulate blood cells so a laser could be used to treat blood viscosity. Because of the increasing concentrations of free intracellular Calcium ions and the action of laser on the plasma composition, it is acceptable to suggest that laser irradiation can lower the number of white blood cells (WBC), red blood cells (RBC), and the reason of that is because of a mechanical change in the blood such as a change in the pores of the surfaces and their fixation.