جدید مالیاتی ادارے اور تقسیم زکوۃ

One of the main features of the property that Islam does not allow the wealth is concentrated around few peoples; any group or class of society, but according to Islamic point of view money should be in circulation so that poor class of the society could enjoy this blessing from Almighty Allah. Zakat Distribution System is a system of fair procedure for this world by Islam; if it is implemented with true spirit of Islam it can end poverty from the society. Islam obligate rich people of the society to distribute Zakat from their wealth amongst poor people however Islam has ordered not to receiver Zakat more than their needs so that it could be distribute to other poor people of the society. Zakat is an important and has significance in Islam. Islamic law imposed the duty on the Islamic government to collect Zakat from the rich and distribute it to the poor of the society, which caused not only undermined the dignity of the poor. Islamic law imposed the duty on Islamic government to take steps of receiving Zakat. If the government imposed the proper procedures in current banks and other financial institutions to receive Zakat from the rich people of the society and distribute it amongst the poor of the society than it could help to get rid of poverty from the society and it also help for the stability of the economy of any Country?

Kinetic Simulation, Sensitivity Analysis of Fission Product Activity and Source Term Evaluation for Typical Accident Scenarios in Nuclear Reactors

Saeed Ehsan Awan, PhD, Department of Physics & Applied Mathematics, PIEAS, June 2012. "Kinetic Simulation, Sensitivity Analysis of Fission Product Activity and Source Term Evaluation for Typical Accident Scenarios in Nuclear Reactors”; Supervisor: Dr. Nasir. M. Mirza; Co-Supervisor: Dr. Sikander M. Mirza; Department of Physics & Applied Mathematics, PIEAS, Nilore 45650, Islamabad. With growing demands of safe and reliable energy resources worldwide, nuclear power plants present viable option. A two third majority of these plants are PWRs. In comparison with their competitors, PWRs suffer from significantly higher dose rate due to radioactivity in the primary circuit which is dominantly contributed by corrosion and followed by fission products leakage from fuel. There has been extensive investigation in developing corrosion resistance alloys. But the problem of corrosion product activity in primary circuit has aggravated in view of trend towards high burn-ups, high temperatures, and longer-life time reactors. Under this scenario, the significance of fission products releases becomes even higher. The fission product activity (FPA) is considered to be the second leading contributor towards prevalent radiation levels in Pressurized Water Reactors (PWRs). The elevated radiation level results in delay and prolongation of routine repair/maintenance tasks of reactor’s cooling system, which not only reduces its effectiveness but also results in several million dollars revenue loss per power plant annually. However the reliable estimates of fission product activity (FPA) are also significant for the evaluation of fuel performance, assessment of radiological consequences in case of any accident releasing radioactivity and scheduling repair/maintenance tasks. The detailed knowledge about radioactivity build up and sensitivity analysis of fission product activity (FPA) is essential for reducing the plant maintenance time, which also helps to reduce the dose for plant operators and general public. In this work, first a model is developed for dynamic and static sensitivity analysis of fission product activity in primary coolant of typical pressurized water reactor (PWR). It has been implemented in the FPCART based computer program FPCART-SA that carries out sensitivity analysis of fission product activity (FPA) using both static as well as dynamic approaches. For long steady power operation of reactor, the computed values of normalized static sensitivity have been compared with the corresponding values obtained by using the dynamic sensitivity analysis. The normalized sensitivity values for the reactor power (P), failed fuel fraction (D), Coolant leakage rate (L), total mass of coolant (m) and the let down flow rate (Q) have been calculated and the values: 1.0, 0.857, -2.0177 × 10-6, 2.349 × 10-4, -2.329 × 10-4 have been found correspondingly for Kr-88 with the dominant values of fission product activity (FPA) as 0.273 μCi/g. In the second part of this study, evaluation of time dependence of source term has been carried out for a typical reactor system. The modeling and simulation of release of radioactivity has been carried out by developing a computer program FPARA which uses the ORIGEN2 code as subroutine, for core inventory calculations. Time dependent release of fission product activity to the containment and air has been simulated for loss of coolant accident scenarios. For noble gases, iodine and for aerosols, the release rate studies have been carried out for different leakage rates from containment. Effects of fraction of source in the coolant that is directly available after the accident on volumetric fission product activity were studied. Results show that volumetric activity in the containment air for different fission products remains strong function of decay constants, leakage rates, retention factors, deposition rates and fractional release rates.