Study was made on the optical properties of Ge2oSe8othinfilms prepared by vac-uum evaporation as radiated by (0,34,69) Gy of 13 ray.The optical band gab Eg and tailing band A.Et were studied in the photon energy range ( 1 to 3)eV. The a-Ge20Se8o film was found to be indirect gap with energy gap of (1.965,1.9 , 1.82) eV at radiated by B ray with absorption doses of (0,34,69)Gy respectively.The Ea and AEt of Ge20Se80 films showed adecrease in E8 and an increase in AEt with radiation. This be-havior may be related to structural defects and dangling bonds.

 Additive aluminum powder to the polystyrene to prepare the composites Polystyrene– Aluminum.The samples were prepared by using mechanical  compressed method at low pressure and a temperature 120°C.         Measurements  of absorbance and reflectance spectra were carried out by UV-Visible  spectrophotometer , the effect of additive aluminum  on the optical band  gap Eop and  optical constants ( refractive index n, extinction coefficient k ,dielectric constant ε and optical conductivity σop)  were studied for the prepared composites .         Results showed a decrease in the Eop with increasing  perc

  The Silver¹Indium¹Selenide (AgInSe₂) (AIS) thin¹films of (300¹Â±20) nm thickness  have been¹prepared²from the compound alloys²using thermal evaporation² technique onto the glass²substrate at room temperature, with a deposition rate²(3±0.1) nm²sec^-1.

The²structural, optical and electrical³properties have been studied³at different annealing³temperatures (Ta=450, 550 and 650) K.

The amount³or (concentration) of the elements³(Ag, In, Se) in the  prepared alloy³was verified using  an

PMMA (Poly methyl methacrylate) is considered one of the most commonly used materials in denture base fabrication due to its ideal properties. Although, a major problem with this resin is the frequent fractures due to heavy chewing forces which lead to early crack and fracture in clinical use. The addition of nanoparticles as filler performed in this study to enhance its selected mechanical properties. The Nano-additive effect investigated in normal circumstances and under a different temperature during water exposure. First, tests applied on the prepared samples at room temperature and then after exposure to water bath at (20, 40, 60) C^° respectively. SEM, PSD, EDX were utilized for samples evaluation in this study. Flexural

Lasers, with their unique characteristics in terms of excellent beam quality, especially directionality and coherency, make them the solution that is key for many processes that require high precision. Lasers have good susceptibility to integrate with automated systems, which provides high flexibility to reach difficult zones. In addition, as a processing tool, a laser can be considered as a contact-free tool of precise tip that became attractive for high precision machining at the micro and nanoscales for different materials. All of the above advantages may be not enough unless the laser technician/engineer has enough knowledge about the mechanism of interaction between the laser light with the processed material. Several sequential phenom

The effect of solution heat treatment on the mechanical properties of Aluminum-Copper alloy. (2024-T3) by the rolling process is investigated. The solution heat treatment was implemented by heating the sheets to 480 C° and quenching them by water; then forming by rolling for many passes. And then natural aging is done for one month. Mechanical properties (tensile strength and hardness) are evaluated and the results are compared with the metal without treatment during the rolling process. ANSYS analysis is used to show the stresses distribution in the sheet during the rolling process.  It has been seen that good mechanical properties are evident in the alloy without heat treatment due to the strain hardening and also the mechanical

In this paper, a new approach was suggested to the method of Gauss Seidel through the controlling of equations installation before the beginning of the method in the traditional way. New structure of equations occur after the diagnosis of the variable that causes the fluctuation and the slow extract of the results, then eradicating this variable. This procedure leads to a higher accuracy and less number of steps than the old method. By using the this proposed method, there will be a possibility of solving many of divergent values equations which cannot be solved by the old style.

          In this paper, magnesium oxide nanoparticles (MgO NPS) have been prepared and characterized and its concentration effect has been studied on polymers surface (MgO NPS). The results showed that the degradation of poly methyl methacrylate increased when using such metal oxide. The results also showed that the metal oxide increased the degradation of poly methyl methacrylate. X-ray diffraction, scanning electron microscopy, atomic force microscopy were used to study the morphological characteristics and size of nano MgO particles analysis.  Films were prepared by mixing the different masses of MgO NPS (0.025, 0.05, 0.1, 0.2 and 0.4) % with a polymer solution ratio (W/V) 7 %. Photo-

• Identifying the visual culture skills of students of the College of Education for Pure Sciences / Ibn Al-Haytham.
• Identifying the statistically significant differences in the visual culture skills of students of the College of Education for Pure Sciences / Ibn Al-Haytham according to the gender variable.

And the descriptive approach was used, due to its relevance to the nature of the research objective.

To verify this, the visual culture skills test consisted of (22) items of the multiple choice type, where the (Koder Richardson 20) equation was applied to calculate the stability of the visual culture skills test. For the skill of writing