In this work, the mass attenuation coefficient, effective atomic number and half value layer parameters were calculated for silicate (SiO2) mixed with various levels of lead oxide and iron oxide as reinforced materials. SiO2 was used with different concentrations of PbO and Fe2O3 (25, 50 and 75 weight %). The glass system was prepared by the melt-quenching method. The attenuation parameters were calculated at photon energies varying from 1keV to 100MeV using the XCOM program (version 3.1). In addition, the mass attenuation coefficient and half value layer parameters for selected glass samples were experimentally determined at photon energies 0.662 and 1.28 MeV emitted from radioactive sources 137Cs and 22Na respectively in a collimated narrow beam geometry set-up using 2"x2" NaI (Tl) scintillation detector. These values are found to be in agreement with the values computed theoretically. Moreover, these results were also compared with those for the commercial window glass. The effective atomic number ( Zeff ) and half value layer (HVL) results indicate that pbO+SiO2 was better gamma ray attenuation than Fe2O3+SiO2 and commercial window glass. This indicates that PbO+SiO2 glasses can be used as gamma ray shielding in replace of both of them in this energy range.
In the current Windows version (Vista), as in all previous versions, creating a user account without setting a password is possible. For a personal PC this might be without too much risk, although it is not recommended, even by Microsoft itself. However, for business computers it is necessary to restrict access to the computers, starting with defining a different password for every user account. For the earlier versions of Windows, a lot of resources can be found giving advice how to construct passwords of user accounts. In some extent they contain remarks concerning the suitability of their solution for Windows Vista. But all these resources are not very precise about what kind of passwords the user must use. To assess the protection of pa
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The structural, optical properties of copper oxide thin films ( CuO) thin films which have been prepared by thermal oxidation with exist air once and oxygen another have been studied. Structural analysis results of Cu thin films demonstrate that the single phase of Cu with high a crystalline structure with a preferred orientation (111). X-ray diffraction results confirm the formation of pure (CuO) phase in both methods of preparation. The optical constant are investigated and calculated such as absorption coefficient, refractive index, extinction coefficient and the dielectric constants for the wavelengths in the range (300-1100) nm.
The synthesis of new substituted cobalt Phthalocyanine (CoPc) was carried out using starting materials Naphthalene-1,4,5, tetracarbonic acid dianhydride (NDI) employing dry process method. Metal oxides (MO) alloy of (60%Ni3O4 40%-Co3O4 ) have been functionalized with multiwall carbon nanotubes (F-MWCNTs) to produce (F-MWCNTs/MO) nanocomposite (E2) and mixed with CoPc to yield (F-MWCNT/CoPc/MO) (E3). These composites were investigated using different analytical and spectrophotometric methods such as 1H-NMR (0-18 ppm), FTIR spectroscopy in the range of (400-4000cm-1), powder X-rays diffraction (PXRD, 2θ o = 10-80), Raman spectroscopy (0-4000 cm-1), and UV-Visib
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The thin films of cadmium oxide (CdO) were deposited using the SILAR (Successive ionic layer absorption and reaction) method at various deposition cycles. CdO thin films were made on glass substrates at a temperature of 95°C, using a cadmium acetate source material and an ammonium hydroxide solution. One of the main criteria that impact the quality of thin films is the number of deposition cycles. The size of the crystals decreases with the increase in the number of cycles from 33.7 nm at the immersion cycle 10 to 22.7 nm at the immersion cycle 20, as shown by the X-ray diffraction results. The optical band gap energy of the films reduces as the number of deposition cycles increases, while the transmittance of the Cadmium oxide film i
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Objective This study evaluated the effects of adding titanium oxide (TiO2) nanofillers on the tear strength, tensile strength, elongation percentage, and hardness of room-temperature-vulcanized (RTV) VST50F and high-temperature-vulcanized (HTV) Cosmesil M511 maxillofacial silicone elastomers. Methods Two types of maxillofacial elastomers, VST50F RTV and Cosmesil M511 HTV, were used. Nano-TiO2 powder was applied as a nanofiller. A total of 120 specimens were fabricated, 60 each of VST50F and Cosmesil M511. The specimens of each type of elastomer were divided into three equal groups on which tests were conducted for tear strength, tensile strength, and hardness i.e., 20 specimens were used for each test. Each group of 20 specimens was further
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The aim of this study was to evaluate the biological importance of the magnitude of oxidative stress, antioxidant and the levels of nitric oxide (NO) in the female patients infected with Toxoplasma gondii by analyzing the levels of erythrocyte malondialdehyde (MDA) as an indicator for the oxidative stress and erythrocyte reduced glutathione (GSH) level as indicator for the antioxidant status and serum nitric oxide levels. This prospective study was conducted on fifty female patients with toxoplasmosis and thirty normal healthy females of comparable age and sex were considered as normal control. A statistically significant difference was found between patients and control group in terms of MDA, GSH and NO levels. A decrease i
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