The optical properties of Poly methyl methacrylate (PMMA) polymers doped by Potassium Iodide with different thickness

Films of pure Poly (methyl methacrylate) (PMMA) doped by potassium iodide (KI) salt with percentages (1%) at different thickness prepared by casting method at room temperature. In order to study the effect of increasing thickness on optical properties, transmission and absorption spectra have been record for five different thicknesses(80,140,210,250,320)µm. The study has been extended to include the changes in the band gap energies, refractive index, extinction coefficient and absorption coefficient with thickness

The MR affect on optical properties for poly (Vinyl alcohol) films

optical properties of pure poly(vinyl Alcohol) films and poly(vinyl Alcohol) doped with methyl red were study, different percentage prepared with constant thickness using casting technique. Absorption, Transmission spectra have been recorded in order to study the optical parameters such as absorption coefficient, energy gap, refractive index, Extinction coefficient and dispersion parameters were measured in the wavelength range (200-800)nm. This study reveals that the optical properties of PVA affect by increasing the impurity concentration

Fiber optics based schemes modeling and simulation of QoS for Wi-Fi scenarios using OPNET modeler

Wireless Fidelity (Wi-Fi) network is created on the IEEE 802.11 standard. Connections for local devices in homes and business arenas are provided by Wi-Fi units. With the growing demand as well as penetration of wireless services, the wireless networks users now assume Quality of Service (QoS) besides performances comparable to what is accessible from secure networks. In this paper, OPNET Modeler is used as module and for the simulation of a fiber optic-based Wi-Fi network within a fixed local area network. The aim of this paper is to evaluate their Quality of service (QoS) performances in terms of Wi-Fi voice-packet delay and End-to-End for both Wi-Fi base fiber and Wi-Fi base line. Many scenarios, with same Physical and MAC parameters, have many subnet networks are implementing with fiber optics baseline in addition to Wi-Fi baseline, were created in the network OPNET simulation tool for obtaining the results. The results of simulation reveal that base line demonstrated more delay than base fiber

Use of sequential extraction methods to evaluate the environmental impact of trace metal in the Iraqi coastlines

The geochemical distribution of several trace metals (lead (Pb), cadmium (Cd), copper (Cu), zinc (Zn), nickel (Ni), chrome (Cr), cobalt (Co) and iron (Fe)) was investigated using five sequential extraction procedures to provide information on their distribution and environmental impacts on the Iraqi coastal sediments. Sediment samples were collected from 16 sites along the coast to determine the concentrations of the above metals. The concentration and ratios of these metals were estimated in the sediment extract (concentration on the exchange surfaces, carbonates, manganese oxides and iron oxides, organic matter and those associated with the remainder) using extraction methods (magnesium chloride, 1 molar of sodium acetate, 0.5 molar of hydroxylamine hydrochloride, 0.2 molar of ammonium oxalate, concentrated nitric acid and 25% of hydrofluoric acid) to extract and separate the above fractions in order. The results indicated that the total sediment content of Pb and Cd were higher than their rate of occurrence in the crust, while copper, zinc, nickel, chrome, cobalt and iron were within those limits. According to the I-geo the metals Cr, Cu and Zn are considered at unpolluted class while Ni and Pb were ranged from moderately to strongly level. On the other had Cd was found at extremely level as its I-geo exceeded the highest-class value. These metals are bonded to different power bonds. Pb, Cr and Co have dominant in exchangeable and carbonates fraction. Iraqi tidal flats is characterized by very high risk considering Cr, Pb, Co and Cu which represented by RAC values, so they can move to the solution to become available for living

Use of sequential extraction methods to evaluate the environmental impact of trace metal in the Iraqi coastlines

The geochemical distribution of several trace metals (lead (Pb), cadmium (Cd), copper (Cu), zinc (Zn), nickel (Ni), chrome (Cr), cobalt (Co) and iron (Fe)) was investigated using five sequential extraction procedures to provide information on their distribution and environmental impacts on the Iraqi coastal sediments. Sediment samples were collected from 16 sites along the coast to determine the concentrations of the above metals. The concentration and ratios of these metals were estimated in the sediment extract (concentration on the exchange surfaces, carbonates, manganese oxides and iron oxides, organic matter and those associated with the remainder) using extraction methods (magnesium chloride, 1 molar of sodium acetate, 0.5 molar of hydroxylamine hydrochloride, 0.2 molar of ammonium oxalate, concentrated nitric acid and 25% of hydrofluoric acid) to extract and separate the above fractions in order. The results indicated that the total sediment content of Pb and Cd were higher than their rate of occurrence in the crust, while copper, zinc, nickel, chrome, cobalt and iron were within those limits. According to the I-geo the metals Cr, Cu and Zn are considered at unpolluted class while Ni and Pb were ranged from moderately to strongly level. On the other had Cd was found at extremely level as its I-geo exceeded the highest-class value. These metals are bonded to different power bonds. Pb, Cr and Co have dominant in exchangeable and carbonates fraction. Iraqi tidal flats is characterized by very high risk considering Cr, Pb, Co and Cu which represented by RAC values, so they can move to the solution to become available for living

Hepatic transformation of Oreochromis Niloticus in lake Maryût in response to xenobiotic exposure

For a long time, Lake Maryût has been recognized as the most productive fishery ground among the northern Delta Lakes. But because of man misuse, the lake has become highly eutrophic and overloaded with several pollution problems. The object of this study is to trace the effects of changes in water and sediments pollution at Lake Maryût on hepatic biotransformation in Oreochromis niloticus and suggest some biomarkers to measure the pollution stress in fish in the lake. Fish were collected from all basins of the lake (five locations) and compared with those collected from the nearby fish farm as a reference. Concentration of cytochrome P-450 can be used as a biomarker for exposure to polycyclic aromatic hydrocarbons (PAHs) since correlation was found between exposure to elevated levels of PAHs in water and sediments and hepatic cytochrome P-450. Data also exhibited that cytochrome b5 concentration was positively correlated with heavy metals content and can be also used as a sensitive bioindicator for environmental pollution with heavy metals. It was found also that high levels of pollution reduced the hepatic glutathione (GST) concentration. In contrast, hepatic glutathione S-transferase (GST) and microsomal hepatic protein content drew a positive correlation with elevated levels of heavy metals in water and sediments.Alex. J. Vet. Sci