In this research, the seasonal Optimal Reliable Frequency (ORF) variations between different transmitter/receiver stations have been determined. Mosul, Baghdad, and Basra have been chosen as tested transmitting stations that located in the northern, center, and southern of Iraqi zone. In this research, the minimum and maximum years (2009 and 2014) of solar cycle 24 have been chosen to examine the effect of solar activity on the determined seasonal ORF parameter. Mathematical model has been proposed which leads to generate the Optimal Reliable Frequency that can maintain the seasonal connection links for different path lengths and bearings. The suggested ORF parameter represented by a different orders polynomial equation. The polynomial equation has been determined depending on different selected parameters (path length, bearing, time (day), months and BUF values). The suggested seasonal ORF parameter was examined for the three stations of the adopted years. The value of the seasonal ORF ionospheric parameter increased with the increase of path length and varies with the bearing between the transmitting and receiving stations also, the seasonal ORF values were higher at maximum solar cycle (2014) than the minimum solar cycle (2009).
The experimental study showed the use of closed cavity wall (the thickness of the cavity 5cm) made a percentage reduction in the cooling load caused by heat gain from the wall by (21.5 %) compared with the conventional wall. also the thermal resistance of the closed cavity was an average (0.2 m2.oC/W).
The experimental results of the study showed that the use of closed cavity wall reduced the average temperature of the inner surface of the wall during the day, and that the reduction was an average (0.45 oC) when compared with the conventional wall , as well as the use of closed cavity wall reduced the temperature difference range of the inner surface of the wall during the day, and that the
... Show MoreA theoretical calculations of the rate constant of electron transfer (ET) in a dye – semiconductor system with variety solvent are applied on system contains safranineT dye with TiO2 in many solvents like water, 1-propanol, Formamide, Acetonitrile and Ethanol.
A matlap program has been written to evaluate many parameters such that, the solvent reorganization energy, effective free energy, activation free energy, coupling matrix element and the rate constant of electron transfer.
The results of the rate constant of electron transfer calculated theoretically are in a good agreement with experimental and theoretical value
... Show MoreAccording to the European Union Water Framework Directive requirements, diatom metrics were used to assess the ecological status of surface waters in the Gaziantep central catchment (Turkey). A total of 42 diatom taxa were identified. A few environmental factors (especially lead, copper, orthophosphate, and chromium) played significant roles on the distribution of diatom assemblages among the sampling stations. The first two axes of the canonical correspondence analysis elucidated 91.6 % of the species–environment correlations with 13.9 % of the cumulative variance of species. The applied diatom indices (TIT – Trophic Index Turkey, TI – Trophic Index, and EPI-D – Eutrophication and/or Pollution Index-Diatom) showed different results
... Show MoreRates of zinc consumption during cathodic protection of a copper pipeline carrying saline water were measured by the loss in weight technique. The study of sacrificial anode cathodic protection of short copper tube using zinc strip extended axially in the pipe revealed that : (i) The increase of zinc consumption with time of exposure (1-3 h's) at different flow rates (turbulent flow) (300-600 l/hr) while the temperature , solution concentration and the pH were fixed at 20ºC, 3.5%wt NaCl, and pH=8 respectively in absence and presence of bacteria.(ii)Increase of zinc consumption with flow rates (300-600 l/hr) at different temperatures (10-40ºC) while solution concentration and time of exposure were fixed at 3.5 %wt NaCl and 3hr's respect
... Show MoreAIM: To evaluate the short-term effectiveness of Gamma knife radiosurgery as a modality of treatment of brain arteriovenous malformation. METHODS: Sixty-three patients with arteriovenous brain malformations underwent Gamma knife radiosurgery included in this prospective study between April 2017 and September 2018 with clinical and radiological with MRI follow up was done at three months and six months post-Gamma knife radiosurgery. By the end of the 12th-month post-Gamma knife radiosurgery, the patients were re-evaluated using digital subtraction angiography co-registered with M.R.I. During the 12 months follow up, CT scan or MRI was done at any time if any one of the patients᾽ condition deteriorated or developed signs and s
... Show MoreCloud computing is the new technological trend for future generations. It represents a new way to use IT resources more efficiently. Cloud computing is one of the most technological models for developing and exploiting infrastructure resources in the world. Under the cloud, the user no longer needs to look for major financing to purchase infrastructure equipment as companies, especially small and medium-sized ones, can get the equipment as a service, rather than buying it as a product. The idea of cloud computing dates back to the sixties of the last century, but this idea did not come into actual application until the beginning of the third millennium, at the hands of technology companies such as Apple, Hp, IBM, which had
... Show MoreA survey of haemoproteids among the eight species of Iraq rallids were carried out in the
middle, south, and west of Iraq. Two haemoproteods were recorded, Haeomproteus porzanae
(Galli-Valerio, 1907) as a new record for Iraq and the new species H. baghdadensis described
from Fulica atra L. collected in the middle of Iraq.
In this study, Cobalt Oxide nanostructure was successfully prepared using the chemical spray pyrolysis technique. The cobalt oxide phase was analysed by X-ray Diffraction (XRD) and proved the preparation of two cobalt oxide phases which are Co3O4 and CoO phases. The surface morphology was characterized by Scanning Electron Microscope (SEM) images showing the topography of the sample with grain size smaller than 100 nm. The optical behavior of the prepared material was studied by UV-Vis spectrophotometer. The band gap varied as 1.9 eV and 2.6 eV for Co3O4 prepared from cobalt sulphate precursor, 2.03 eV and 4.04 eV for Co3O4 prepared from cobalt nitrate precursor, 2.04 eV and 4.01 eV for CoO prepared from cobalt chloride precursor where th
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