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In this research we study the effect of coma aberration on point spread function (PSF) for array synthetic circular obscured aperture. The equation of point spread function (PSF) have been derived for this case, coma aberration is used in different angles for set of obscured circular synthetic apertures, addition to different obscuration ratios, by using MathCAD programs. The results show an increasing the resolving power by using array synthetic circular obscured aperture and coma aberration leads to decrease the secondary peaks for point spread function (Apodization).

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this work is show the effect of quantization on the reconstructed image in fractal image compression FIC method. it is based on zero-mean block matching method, at this method the mean of the range blocks is used instead of traditional offset parameter. This reduces and simplifies the computations of the affine parameters during the encoding process. This method is tested on 8 bits/pixel gray image. The test results conducted on Lena image indicated that the quantization increases compression ratio about (69.6%) and encoding time about (18.6%) but the decreases of PSNR around (0.3%), The quality of the reconstructed image is good either we use the quantization process or not used it.

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Effect of sputtering pressure and partial pressure on structural properties of TiO2 films prepared using DC-sputtering to glass substrate was investigated. sputtering pressures are changed (1.8,2.8,3.8,4.3 pa) at constant O2 /Ar Ratio(5%). Measurements reveal that the TiO2 films at the sputtering pressure 1.8 pa is amorphous , while at increasing pressure to 2.8 pa becomes crystalline with Rutile phase (110) and when we increase the pressure to 4.3 pa get crystalline structure with anatas phase ( 101) .Grain size is calculated per crystalline structure of the anatas and rutile (15.7) nm and(14.2) nm respectively. For constant sputtering pressure (2.8pa) and changedO2/Ar Ratio(10% ,15% ,20% ,25% ,30% , 35%),TiO2 thin films are a amorphous, except percentage (25%) is crystalline with anatas phase (101) and with grain size (15.7 nm).

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Density functional theory was employed to investigate the electronic properties of phynelene and thiophene compounds and their adducts, the interaction between the two structures changes to include six systems. Many important electronic properties were studied in two ways, the vertical energy method and vertical orbital method include the chemical potential, chemical molecular hardness, chemical softness, electrophilic index and polarizability. Full geometry optimization was calculated at the same level of theory. The results showed that the new structures have low chemical hardness with large electrophilicity, and they are more reactive .

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In this paper, energy levels were calculated for two nuclei (14 8O6 ,14 6C8) by applying the nuclear shell model by using modified surface delta interaction (MSDI).The (MSDI) succeeded in energy levels calculation for the configuration (hole-hole ( ,this case facilitated the calculation of many holes outside closed shell by using the configuration (hole-hole). Computer programs were used to calculate important coefficients involved mainly in calculating energy levels include Clebch - Gordan , Racha coefficient and matrix element for two bodies by using modified surface delta interaction. Comparison the current values with the experimental values , it was found current values were in perfect agreement with the experimental values .

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The natural radioactivity due to presence of 238U, 232Th and 40K radionuclides in soil of Kufa zone , Najaf governorate, Iraq were measured by using gamma-ray spectrometry NaI(Tl) "3× 3". The specific activity of the soil samples ranged from 1.76±2.30 to 77.45±2.35 Bqkg-1 with an average of 25.23±2.94 Bqkg-1, from 7.92±1.22 to 42.58±1.75 Bqkg-1 with an average of 20.09±1.11 Bqkg-1 and from 219.58±1176 to 1994.17±16.15 Bqkg-1 with an average of 984.30±11.86 Bqkg-1 for 238U, 232Th and 40K respectively. The study also examined some radiation hazard indices such as radium equivalent activity (Raeq), Absorbed Dose rates (D), External Hazard Index (Hex) and Internal Hazard Index (Hin). These calculated hazard indices to estimate the potential radiological health risk in soil. The radium equivalent activity (Raeq) values found to vary from 67.80 to 285.80 Bqkg-1, with the average value of 129.74 Bqkg-1, which was less than permitted value (370 Bqkg-1). The absorbed dose rates, ranged from 32. 1 to 142.08 nGyh-1, with a average value of 65.17 nGyh-1 that higher than the permissible limit of 55 nGyh-1. The external and internal hazard index of soil samples were less than unity

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This work deals with structural and electronic properties of trihydroborane -carbonyl BH3-CO as a donor-acceptor molecular system. B3LYP density functional theory was employed with various basis sets to calculate some structural and electronic properties for this system. The calculations include the bond length and angles between atoms. And some electronic properties of the studied compound were investigated include the total energy, electronic states, electron affinity, chemical hardness, softness and electrophilic index. The results show that 6-31G (d, p) level of theory gave good agreement values of geometrical parameters with experimental data in comparison with other levels.

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In this work, Radon concentrations in drinking water were measured at 42 locations in Al- Najaf cities, using RAD-7 radon monitoring system of Durridge company USA. The annual effective dose for all samples of drinking water were estimated by equations depending on UNSCEAR organization. It is found that the radon concentrations in samples in studied area were varied from (2.43±0.879 Bq/m3) to (225.5±12.657 Bq/m3), while the mean annual effective dose of Ingestion and Inhalation varied from (0.017739 μS.y-1) to (1.64615 μS.y-1) and (0.088807 μS.y-1) to (0.704526 μS.y-1) respectively. When the results were compared of radon concentrations with the internationally recommended reference levels (World healthy Organization limit 500 Bq/m3) and the mean effective annual dose for radon in drink water normal limits of world (1 mSv/y), there were no indications of existence of radon problems in the water sources in this survey. therefore the drinking water in Al-Najaf city is safe as far as radon concentration is concerned.

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There are two important types of basic gas-insulated apparatus used by electric power industry: i.gas-insulted transmission lines and ii.gas-insulated transformers.SF6−HeMixture are considered to be used in circuit breakers, helium has a very blow dielectric strength (~3% that of SF6 in uniform fields) and contributes virtually nothing to the dielectric strength of the mixture. Helium however, complements SF6 in terms of its cooling capacity because it is very light, and does not react chemically eitherSF6, or the gas impurities present in commercialSF6, or the system components. The motion of electrons in plasma gas sulfur hexafluoride (SF6) and its mixture with inert gas He in the present of applied uniform electric field is simulated by using the numerical solution of Boltzmann's transport equation technique. The numerical solutions are utilized within the international computer code program called ''NOMAD'' written in FORTRAN 77, by using the Finite difference method. The energy distribution function and the swarm transport parameters of electron accelerated by DC electric field in a mixture of SF6−He , are evaluated and compared with experimental result of drift velocity (vd), average energy (ϵ̅) ,characteristic energy (ϵk) , diffusion coefficient (D) ,and electron mobility (μ). We conclude that the calculation value has a percentage agreement with international published experimental value over the range of E/N in Td units (E is the electric field and N concentration gas molecules). One can interpret the existence percentage error to the accuracy of the using cross section data for both elastic and inelastic collisions, since their exist many laboratory published data.

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A quantum mechanical model used to study, the electron transfer reaction for the titanium dioxide TiO2,tin dioxide SnO2,and Indium tin oxide ITO semiconductor and the redox thiopyronine (Tp) molecule dye. Theoretical method was adapted to calculate the coupling matrix element coefficient for semiconductor /dye state and the rate constant of electron transfer reaction. The calculated results of rate constant were compared with experimental and theoretical results show good agreement with these results.

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In this research the mathematical model of surface electric currents induced on axisymmetric conductive body of revolution has been formulated and solved numerically by implementing the (MoM) method. Computer simulation was developed to solve the model numerically .The resulted radiation pattern was sketched Reduction of sidelobe and beamwidth thickness was achieved by increasing the number of a apertures and changing their corresponding interspaces.

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