In this work, solid random gain media were fabricated from laser dye solutions containing nanoparticles as scattering centers. Two different rhodamine dyes (123 and 6G) were used to host the highly-pure titanium dioxide nanoparticles to form the random gain media. The spectroscopic characteristics (mainly fluorescence) of these media were determined and studied. These random gain media showed laser emission in the visible region of electromagnetic spectrum. Fluorescence characteristics can be controlled to few nanometers by adjusting the characteristics of the host and nanoparticles as well as the preparation conditions of the samples. Emission of narrow linewidth (3nm) and high intensity in the visible region (533-537nm) was obtained.
Background: Endodontically treated teeth have low resistance to fracture against occlusal forces. The strengthening effect of bonded esthetic onlay restoration on weakened tooth has been reported. This study aimed to assess the fracture resistance of endodontically treated premolars restored with composite with and without cuspal coverage by using direct and indirect techniques. Indirect technique done by CAD/CAM system (computer aided design –computer aided manufacturer) and laboratory processing. Material and methods: Forty human extracted maxillary premolars of approximately comparable sizes were divided into four groups: Group (A): Ten endodontically treated teeth directly filled with Filtek Z250xt without cuspal coverage. Group
... Show MoreIn the present study, advanced oxidation treatment, the TiO2 /UV/H2O2 process was applied to decolorisation of the reactive yellow dyes in aqueous solution. The UV radiation was carried out with a 6 W low-pressure mercury lamp. The rate of color removal was studied by measuring the absorbency at a characteristic wavelength. The effects of H2O2 dosage, dye initial concentration and pH on decolorisation kinetics in the batch photoreactor were investigated. The highest decolorisation rates were observed (98.8) at pH range between 3 and 7. The optimal levels of H2O2 needed for the process were examined. It appears that high levels of H2O2 could reduce decolori
... Show MoreIn the present work, the surface properties of mixed binary surfactants containing sodium dodecylbenzene sulfate (SDBS) and Tween 80 (TW80) surfactants in aqueous solutions were studied at temperature 293 K using surface tension measurements. The critical micelle concentration (cmc) magnitude for both individual surfactants and their mixtures were established the obtained results revealed that the magnitude of cmc of the mixtures are less than the magnitude of individual surfactants and decrease with the increase in Tween 80 percent in solution which indicate the nonideal mixing of the two surfactants. The values of molecular interaction parameters and the mole fraction of surfactants in the micelle (X1) were calculated
... Show Morerepresenting the media and communication problems and phenomena fertile material and of great importance in the media research, especially as they relate to various aspects of life and its impact on the culture of the community and on individuals and public opinion about the behavior of the various issues. The media incitement to violence and hatred of the most prominent media phenomena that increased the danger and expanded not at the local level, but also in the world. So we found it is important to study this problem from the standpoint of academic and professional. And according to the progress of this research is trying to answer a number of questions including:
A. What are the Iraqi Satellite TV channels most watched and follow
Microbial antibiotics resistance is considered a serious health issue in the Middle East and developing countries. In this study, the Fe2O3 nanoparticles was prepared chemically, and the particles size and shape were analyzed by using Scan electron microscope (SEM) and X-Ray diffraction (XRD). Different concentration of Fe2O3 nanoparticles were used and examined on E.coli and S. aureus. Using liquid dilution and in vitro cytotoxicity assay by microplate toxicity test (MTT). The microbial cell metabolic activity was measured on gram-negative, gram-positive bacteria and fungi after treating with different concentrations of Fe2O3 nanoparticl
... Show MoreAim: This abstract aims to highlight the critical nature of climate change as a pressing challenge facing humanity in the 21st century. It underscores the severe consequences it poses to essential facets of human existence, including water and energy resources, agricultural production, and the broader environmental systems. Method: The abstract primarily utilizes a descriptive approach to emphasize the impact of climate change on the Middle East, particularly the Arab region. It relies on a review of existing knowledge and data related to climate change and its effects on ecosystems and drought patterns. Results: The abstract outlines the direct and indirect repercussions of climate change on human life and the environment. It draws atten
... Show MoreAl-Ruhbah region is located in the southwest of Najaf Governorate. A numerical model was created to simulate groundwater flow and analyze the water quality of the groundwater, by developing a conceptual model within the groundwater modeling system software. Nineteen wells were used, 15 for pumping and four for observation. A three-dimensional model was built based on the cross-sections indicating the geologic layers of the study area, which were composed of five layers. When a distance of 1,000 m between the wells was adopted, 135 wells can be operated simultaneously. These wells were hypothetically operated at 6, 12, and 18 h intervals, with a discharge of 200, 430, and 650 m
Investigation of the adsorption of acid fuchsin dye (AFD) on Zeolite 5A is carried out using batch scale experiments according to statistical design. Adsorption isotherms, kinetics and thermodynamics were demonstrated. Results showed that the maximum removal efficiency was using zeolite at a temperature of 93.68751 mg/g. Experimental data was found to fit the Langmuir isotherm and pseudo second order kinetics with maximum removal of about 95%. Thermodynamic analysis showed an endothermic adsorption. Optimization was made for the most affecting operating variables and a model equation for the predicted efficiency was suggested.
Modern communication and media technology has pioneered new horizons and curried out deep changes in the various fields of social life, It effected enormously human communication as well.
Content one Who late the developments which have effected the social relations ،due to the new media ،especially Face book ,will certainly notice the far cry changes of the social relation net which has been effected ,in a way or another ،the accelerated development ،under the appearance of the so called the virtual society .
Face book has embodied the means – communication ,which has become an important turn point in the social communication .
It is the point the present paper tries to expose an discuss by a field study curried on a sam