The effects of solar radiation pressure at several satellite (near Earth orbit satellite, low Earth orbit satellite, medium Earth orbit satellite and high Earth orbit satellite ) have been investigated. Computer simulation of the equation of motion with perturbations using step-by-step integration (Cowell's method) designed by matlab a 7.4 where using Jacobian matrix method to increase the accuracy of result.
The influence of 5-10 kHz audio frequency on the power dissipation in ac discharge of argon gas was studied experimentally, at pressures 50-80 mTorr and electrodes separation 10 cm (pd range 0.5-0.8 Torr.
cm). The measurements have shown that the discharge behavior in the ac circuit is equivalent to a series RC circuit. It is observed that the variation curve of discharge power P with the frequency f is approximately has a Gaussian shape. It is also observed that the curve of Pm- pd is the inverse of Paschen curve, where Pm is the maximum power in the frequency range. The time of breakdown is estimated from the curve of P- f.
Previous reports demonstrated the effectiveness of silibinin hemisuccinate as a potential intraocular pressure-lowering agent. The exact mechanism by which silibinin exerted this effect has not yet been documented, but might suggested to interfere with aqueous humor formation. The present study was designed to evaluate the comparative efficacy of silibinin as IOP lowering agent to that of betaxolol in normotensive rabbits, and the interaction of silibinin with betaxolol as a way for investigating the possible mechanism of action of silibinin in this respect. The effects of instillation of 0.75% silibinin solution and 0.5% betaxolol eye drops in the eyes of normotensive rabbits were evaluated using indentation tonometry. The results showe
... Show MoreSloped solar chimney system is a solar chimney power plant with a sloped collector. Practically, the sloped collector can function as a chimney, then the chimney height can be reduced and the construction cost would be reduced.The continuity, Naver-stockes, energy and radiation transfer equations have been solved and carried out by Fluent software. The governing equations are solved for incompressible, 3-D, steady, turbulent standard model with Boussiuesq approximation to develop for the sloped solar chimney system in this study and evaluate the performance of solar chimney power plant in Baghdad city of Iraq numerically by Fluent (14) software with orking conditions such as solar radiation intensity (30
... Show MoreThe present paper is an experimental study to improve the productivity of the conventional solar still. This done by modifying conventional still in a way that the distilled basin is larger than distillation basin, thus providing an increase in the condensation surface and speeding up the condensation process. Moreover, increase in the dimensions of the distilled base helps coupling reflective panels to the distilled base to reflect incident solar radiation to the distillation basin. For this purpose , two solar stills were made, one conventional designand another made according to the proposed design. The two solar stills were tested during the period from February to July 2009 under varying weather conditions of Basra, Iraq (latitude o
... Show MoreSpot panchromatic satellite image had been employed to study and know the difference Between ground and satellite data( DN ,its values varies from 0-255) where it is necessary to convert these DN values to absolute radiance values through special equations ,later it converted to spectral reflectance values .In this study a monitoring of the environmental effect resulted from throwing the sewage drainages pollutants (industrial and home) into the Tigris river water in Mosul, was achieved, which have an effect mostly on physical characters specially color and turbidity which lead to the variation in Spectral Reflectance of the river water ,and it could be detected by using many remote sensing techniques. The contaminated areas within th
... Show MoreHigh intraocular pressure (IOP) is a recognized risk factor for glaucoma and optic nerve injury, and it is one of the primary causes of vision loss globally. Anabasis articulata (AA) is a desert plant found in Iraq. The extract of AA is used to cure diabetes, fever, eczema, and kidney infections. The aim of the study is to evaluate the antioxidant effect of methanol extract of AA on intraocular pressure in the glaucoma rat model. Forty-two rats were allocated into seven groups, each with six animals:: group 1 (normal), group 2 (control), in which animals were induced to have elevated IOP by betamethasone suspension injection, groups 3,4 and 5 for evaluating the effect of 50,100 and 150 mg/kg/day of the tested extract, respective
... Show MoreRadiation measuring devices need to periodic calibration process to examine their sensitivity and the extent of the response. This study is used to evaluate the radiation doses of the workers in the laboratories of the Directorate of Safety as a result of the use of point sources in calibrating of the devices in two ways, the first is the direct measurement by the FAG device and the others using RESRAD and RAD PRO programs. The total doses values using FAG were (2.57 μSv/y, 102.3 μSv/y and 20.75 μSv/y for TLD laboratory, Gamma spectroscopy analyses (GSA) laboratory and equipment store respectively, and the total doses that calculated using RESRAD and RAD PRO were 1.518 μSv/y, 76.65 μSv/y and 21.2 μSv/y for the above laboratories. t
... Show MoreThe present study investigated the impact of fuel kind on the emitted emissions at the idling period. Three types of available fuels in Iraq were tested. The tests conducted on ordinary gasoline with an octane number of 82, premium gasoline with an octane number of 92, and M20 (consist of 20% methanol and 80% regular gasoline). The 2 liters Mercedes-Benz engine was used in the experiments.
The results showed that engine operation at idle speed emits high levels of CO, CO2, HC, NOx and noise. The produced emission levels depend highly on fuel type. The premium gasoline (ON=92) represents the lower emissions level except for noise at all idling speed. Adding methanol to ordinary gasoline (ON=82) showed high levels of emi
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