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4th International Conference on Radiation Sciences and Applications, 13-17/10/2014, Taba
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Session VII:Physics
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4th International Conference on Radiation Sciences and Applications, 13-17/10/2014, Taba
Simulation and Optimization of Electromagnet Isotopes SeparationUsing Freeman Ion Source
A. M. Hassan, S. I. Radwan, H. El-Khabeary and A. G. Helal
Accelerators & Ion Sources Department, Nuclear Research Center, Atomic Energy Authority, P.N. 13759, Cairo, Egypt.
ABSTRACT
A simulation study for the electromagnetic isotope separation is per-formed for the beam line attached to the 50 keV Freeman ion source. The simulation is used to examine the electromagnetic which attached to the ion source for isotopes separation. The beam characteristics of the Freeman ion source are studied in order to evaluate the degree of matching between the ion source and mass-separator optics. The simulation reveals necessary modifications and new optical elements which attached to the beam line to improve the resolution of mass separation and also the beam quality for other scientific applications as, ion implantations and basic research. The beam trajectories in acceleration region have been studied and the modifications in the optical elements along with the beam line transport and the poles shape of the separating magnet design are proposed. The effects of space-charge repulsion on the quality of focusing are compared and it is demonstrated that a simple retardation lens design can be effectively employed at high flux.
Key words: Freeman Ion Source / Electromagnetic Isotopes Separation / Beam Line.
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4th International Conference on Radiation Sciences and Applications, 13-17/10/2014, Taba
Improving the Interface between NPPS and the Electric Grid
H. M. Hassan1, E. A. Eisawy1, T. A. Kandil2, M. A. Elwany2
1- Nuclear and Radiological Regulatory Authority.2- Faculty of Engineering, Al Azhar university.
ABSTRACT
The interface between nuclear power plants (NPPs) and electric grids deserves careful attention especially in low-performance electric power systems. Electrical grids have an important impact in the safe and reliable operation as well as startup/shutdown of NPPs. Conversely, tripping a nuclear reactor may give rise to sizable disturbances in grid parameter (frequency and voltage), which require automated action on the part of grid to maintain the quality of electricity.
One way to improve grid characteristics is using FACTS devices; these devices can regulate the active and reactive power control as well as adaptive to voltage-magnitude control simultaneously because of their flexibility and fast control characteristics. Placement of these devices in suitable location can lead to reduce the total power losses and maintain bus voltages in desired level and so improve voltage stability margins. On the other hand, FACTS devices derive their enhanced controllability using switching converters, so they introducing steady-state waveform distortion. Distortion which in turn propagates through the power system has an adverse impact on losses, telecommunication interference, filter and machine over-heating, and increased current levels, so we can consider FACTS devices as both a part of the power quality problem and a part of its solution.
The first part of this paper will propose an optimization method to optimally locating FACTS devices in proper location on the grid. In the second part we will study the effect of the harmonics generated by these devices on the grid, and will compare the measured values with the IEEE 519 standards.
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4th International Conference on Radiation Sciences and Applications, 13-17/10/2014, Taba
Time dependent advection diffusion equation in two dimensions
Khaled S. M. Essa*, and Sawsan E. M. Elsaid*
Mathematics and Theoretical Physics, NRC, Atomic Energy Authority, Cairo- Egypt
ABSTRACT
In this work, the advection diffusion equation is solved in two dimensional space (x,z) which depends on time using Laplace transform technique to evaluate crosswind integrated of pollutant concentration per emission rate, using boundary layer parameterization. The observed Copenhagen data set is composed of tracer SF6 data from dispersion experiments carried out in northern Copenhagen, we used 20 minutes averaged measured concentration. The comparison between two predicted models and observed data is estimated.
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4th International Conference on Radiation Sciences and Applications, 13-17/10/2014, Taba
Physicochemical studies for Strontium sulfate radiation dosimeter
M.A.H. Rushdia,b,c, A.A. Abdel-Fattahb, Y.S. Solimanb
a- Sudan Atomic Energy Commission, Khartoum, Sudanb- National Center for Radiation Research and Technology, Atomic Energy Authority (AEA), Cairo, Egyptc- Physics Department, Faculty of Science, Cairo University, Egypt
ABSTRACT
Anhydrous strontium sulfate (SrSO4) has shown a promise candidate as a dosimeter for low dose applications producing unique EPR signals with ɣ-rays which it has a linear response relationship (r2=0.999) in the range of 1-100 Gy. The present study extended to evaluate the properties of strontium sulfate dosimeter in high dose range of technology applications. It was observed that the intensity of the EPR signal at g=2.1081 increase with a 3rd polynomial function in the range of 0.10– 15 kGy. In addition, the radical (SO4
-) provides a stable signal with a good reproducibility (0.107%). Other physics characteristic including the collision of mass stopping power dependence of the system and the effect of atomic number in different energy regions were investigated. The uncertainty budget for high doses has obtained from the measurement with value of 3.57% at 2σ confidence level.
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4th International Conference on Radiation Sciences and Applications, 13-17/10/2014, Taba
SIMION Simulation studies for pentode extraction system
B.A. Soliman, M.M. Abdelrahman, and F. W. Abdelsalam
Accelerators & Ion Sources Department, Nuclear Research Center, Atomic Energy Authority, Inchas, Atomic Energy, Cairo, Egypt.
ABSTRACT
A five-electrode system (pentode extraction system) for optimally extracting, singly-charged ion beams has been computationally designed. The presented paper exploits the capabilities of commercial software (SIMION 3D v.7) in tuning up some of the main parameters (current density, extraction voltage and extraction gap width) and conditions needed for the optimal design of the optical system associated with a specified ion source before its fabrication. The space-charge effects expressing the mutual repulsion of charged ions within the ion beam are also considered during the simulation. The studied subject is of great importance especially for nuclear applications etc…. This work addresses the parameteric study and conditions on the performance of an ion-beam extraction system, the trajectories of the particles in the beam being simulated by SIMION. Space-charge effects are accounted for and criteria allowing optimization of the system are proposed. Ion beam trajectories with and without space charge have been determined and, from the results, optimum extraction conditions have been deduced. Simulation of singly charged ion trajectories for a concave meniscus with 4 mm curvature radius was studied with and without space charge has been done using a singly charge argon ion trajectories. Firstly, for a concave meniscus with 4 mm curvature radius, the influence of the current density on the ion beam shape was investigated. Furthermore, influence of the acceleration voltage applied to the second electrode on the ion beam envelope was studied. Finally, the influence of the extraction gap width on the ion beam envelope was also studied.
Key words: Ion Beam Emittance, Pentode extraction system, first and second extraction gap widths.
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4th International Conference on Radiation Sciences and Applications, 13-17/10/2014, Taba
Precise Measurements of Mass Attenuation Coefficients for Some Ceramic Tiles Widely Used in Egypt
M. Omer1, M. A. M. Uosif2, A. El-Kamel1, M.A. Hefni1 and N. Ahmed1
1- Physics Department, Faculty of Science, Assiut University, Assiut, 71516, Egypt.2- Department of Physics, Al-Azhar University, (Assiut branch), Assiut, 71524 Egypt.
ABSTRACT
Mass attenuation coefficients of sixteen ceramic tile samples, widely used in the Egyptian dwellings, have been determined in the energy range from 80 keV to 1.33 MeV. Different point-like radioactive sources have provided the dedicated γ-rays energies. Each source was mounted in a 3 mm collimator to attain a beam like geometry. Mass attenuation coefficients have been determined using the transmission method with a 1.5-inches NaI(Tl) scintillation detector. Precise compositions of all samples have been obtained from the XRF analysis. These compositions were fed into the XCOM software to calculate the theoretical values of mass attenuation coefficients, and then compared with experimental data. The agreements of theoretical and experimental values of mass attenuation coefficient have been found to be within statistical uncertainties. Small amounts of Zn and Zr elements existing in most samples account for the relatively high mass attenuation coefficients observed in our samples.
Key words: Ceramic, Mass attenuation coefficient, XRF
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4th International Conference on Radiation Sciences and Applications, 13-17/10/2014, Taba
Differential Cross Section of K+ Meson with Nucleon and Some Nuclei in Meson exchange Theory at Intermediate Energies
K.M. Hanna, Sh.M.E. Sewailem and A.G. Shalaby
1- Math.and Theor.Phys.Dept., NRC, Atomic Energy Authority 13759, Cairo-Egypt.2- Physics Department, Faculty of Science, Benha University, Benha – Egypt.
ABSTRACT
Differential elastic scattering cross sections for (K+- n), (K+- P), (K+- 2H), (K+- 6Li) and (K+- 12C) at an incident beam momenta Plab < 1 GeV/C (intermediate energy) are calculated in the eikonal approximation, and compared with experimental data over an angular range from 10- 40 degrees. The semi-relativistic optical potentials of the K+-nucleon (K+- N) and nucleus (K+- A) interactions are obtained and interpreted, on the basis of the One-Boson-Exchange (OBE) model where used set of boson parameters suggested by the JÄulich group, to get the radial forms of the interacting potential V(r). In Dirac space the process is based on the exchange of four mesons, one attractive scalar meson and three repulsive vector mesons. In addition, the derived forms for the (K+ -A) potential are utilized orbital density distribution of the nucleon in target-nuclei (shell model), and the relativization effect of kaon beam was studied and shown to play an important role. To evaluate the numerical results for the studied potentials we have used generalize Yukawa-type meson functions.
Key words: Kaon-Nucleon interaction, Kaon-Nucleus interaction, One-Boson-Exchange-Potential (OBE).
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4th International Conference on Radiation Sciences and Applications, 13-17/10/2014, Taba
Thermodynamic Modeling and Study on a Nuclear Desalination Project in Egypt
Y. Rihan, E. Ayoub
Hot Lab. Center, Atomic Energy Authority, Egypt.
ABSTRACT
The desalination of seawater using nuclear energy is a feasible option to meet the growing demand of potable water. Several demonstration programs of nuclear desalination are in progress to confirm its technical and economic viability under country specific conditions, with technical co-ordination or support of International Atomic Energy Agency. In particular, some data from the feasibility studies carried out in Egypt for its nuclear power and desalination project are presented. Economic research on further water cost reduction includes investigation on utilization of waste heat from different nuclear reactor types for thermal desalination, preheat reverse osmosis using condenser cooling water return as feed and hybrid MED–RO desalination systems. An analytical model of the thermo vapor compression (TVC) desalination process was developed to investigate the effect of design and operating parameters on parameters controlling the cost of producing fresh water from TVC process. Steady state mass and energy balances as well as empirical correlations derived from experiments were used to model the TVC, which was coupled to a cogeneration nuclear power plant to supply the needed steam for the desalination.
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4th International Conference on Radiation Sciences and Applications, 13-17/10/2014, Taba
Natural Radioactivity and Excess Lifetime Cancer Risk of Sand Quarries in Assuit Governorate ,Upper Egypt
Mahmoud M. Abd El-Khalek.
Faculty of science, Assiut University
ABSTRACT
The concentration of natural occurring radionuclides 226Ra, 232Th and 40K and its radiological hazard of sand samples, have been collected from twenty one sand quarries in Governorate, Upper Egypt is presented in this paper. The measurements have been done by using γ-ray spectrometer (NaI (Tl) 3” × 3” ) . The obtained values were less than the world average values suggested by UNSCEAR, 2000. Absorbed dose rate (D), Annual effective dose equivalent (AEDE), the external hazard index (Hex), the internal hazard index (Hin), Gamma index (Iγ), Excess lifetime cancer risk (ELCR) and Annual gonadal dose equivalent (AGDE) have been calculated to evaluate the radiation hazards associated with using these sand samples as building material. With regard to the obtained results, all materials would not present a significant radiological hazard when used in building constructions.
