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[en] The application of nano silica extracted from kaolinite, bentonite and rice straw is proposed as treatment material for the purification of primary coolant water of pressurized water reactors. Three elements were used to simulate some radionuclides that can be released in the primary coolant water namely, strontium, nickel and cobalt. Various batch experiments were performed including selection of efficient sorption nano material, optimum operational weight ratio (element/nano material), selectivity of the nano silica for elements used, determination of the equilibrium curve of sorption process, and desorption behavior of nano material with ph and temperature variation. The samples were analyzed using the inductively coupled plasma emission spectrometer. Silica of kaolinite, bentonite and rice straw showed the same results in the efficiency/ capability removing the three elements used. Silica form of rice straw has been selected as nano-treated materials for economic and environmental reasons. The sorption process reached equilibrium after 30 min approximately. The experiments demonstrated that the sorption reaction of elements by the nano-silica is an irreversible reaction with the change of temperature and ph. The obtained results indicated that using the nano silica increased the safety margin of the treatment stage in the multi barrier concept
[en] This study assessed the clinical usefulness of the 2D-Array Seven 29 by comparing the dose of Photon Beam for water phantom, 2D-array and Treatment Planning System in five Field sizes. The experimental equipment included the linear accelerator, treatment planning system (TPS), water phantom, 2D-Array, solid phantoms, and two types of ionization chambers (Semi flex and Pinpoint). The distance between the ray source and the center of the ion chamber was fixed to SSD of 100 cm during the experiment. The field size was 10× 10 cm2 and the radiation energies of the photon beam were 6 MV and 15 MV. The energy fields sizes involved (1×1, 2×2, 3×3, 4×4, 5×5,). The relative deviation ratio of the TPS in water phantom and TPS to 2d array in the solid phantom was calculated. The measured doses in standard phantom were lower than TPS values for small field dimensions (less than 3×3 cm2). The data measured by 2D-Array for fields 2×2 and 3×3 cm2 within ±2% indicated a good accuracy of measurement planning system for field size 1×1cm2. The measured doses in the standard phantom was lower than the TPS values for small field dimensions and the data measured by 2D-Array for 6 MV shows mild differences between the TPS and the experimental data. A slight difference appeared between the TPS and the experimental data using 2D-Array for 15 MV. The results were the same for the TPS and the measured data, at only a field dimension of 1×1 cm2. The measured data increased as field area enlarged from 2×2 to 5×5cm2 by a constant value of 4%
[en] In this study, Abu Tartur open-pit Phosphate mine and underground tunnels have been studied from radiation safety point of view. Radon, radon daughters and thoron daughters were measured by collecting (31) samples from (5) main sites that represent the process of Phosphate mining. Results of radon, radon daughters and thoron daughters, in case of open-pit mining ranged from 1.37 to 131.52 Bq m-3, 0.000099 to 0.0024 WL, and 0 to 0.92 Bq.m-3 respectively. For postpone tunnels, results of radon, radon daughters, thoron daughters ranged from 411.55 to 2539.27 Bq m-3, 0.056 to 0.37 WL, and 1.26 to 3.89 Bq.m-3 respectively. Also, gamma radiation levels, surface contamination and effective annual dose were measured. Gamma radiation levels ranged from 0.07 to 0.6 mSv/h for open-pit mine and from 0.24 to 0.5 mSv/h for tunnels. Surface contamination measurements gave normal readings for open-pit mining and 7.1 in underground mine. The effective annual dose ranged from 0.033 to 0.153 mSv/y for open-pit and 4.948 mSv/y for tunnels. The results, in case of open-pit mine, are lower than permissible limits determined by UNSCEAR, 2010 while exceeds the permissible limits in case of underground tunnels. So the open-pit mining is much safer from the occupational radiation protection point of view
[en] In this study, the copolymer hydrogel was prepared by copolymerization of gum arabic (GA), Poly (vinyl alcohol) (PVA) using gamma irradiation. The factors affecting the preparation conditions of (GA/PVA) copolymer hydrogels such as copolymer composition, copolymer concentration and irradiation dose were investigated. The swelling property of the prepared hydrogels was studied and the results showed that the swelling percent increased with increasing concentration of GA in feed solution and reached to the equilibrium state at 6 h. The obtained hydrogels were characterized using thermal gravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR). The morphology of the prepared hydrogels was examined by Scanning Electron Microscopy (SEM). The mechanical properties of copolymer hydrogel [tensile strength (TS), elongation at break (Eb) and compressive test (CS)] were measured using an Instron testing machine. The prepared hydrogels were investigated for the removal of Cu2+, Co2+, Pb2+and Cd2+ ions from industrial wastewater. The parameters influencing the metal uptake, for example, ph, time, GA content and temperature were investigated. The adsorption of metal ions by hydrogel increases as follows Pb2+> Cu2+> Co2+ > Cd2+. The prepared copolymer hydrogel possessed a good affinity towards the adsorption of metal ions, which makes them acceptable for the treatment of industrial Wastewater from such metal ions
[en] Air quality of public buildings is an important issue to assess human health. School and university buildings represent an important category of indoor environments. This study aims at evaluating the concentration and size distribution of fungal and non-biological aerosol particles in classrooms of Minia University, Egypt. In addition, the inhalable fractions were determined and indoor exposure dose (IED) of fungi and aerosols were estimated for the students. A six-stage Andersen impactor was used for collecting the fungal particles and Berner cascade impactor was used for sampling the non-biological aerosol particles. Indoor average concentration of fungi was 307±102 CFU/m3. The most frequently isolated genera were Aspergillus niger with concentration 175±85 CFU/m3 representing about 57% of the of the total collected fungi. Aspergillus flavus represents about 31% of the total fungi with concentration 96±32 CFU/m3. A low concentration 36 ±12 CFU/m3 of Penicillium was investigated representing only 12% of the total collected fungi. The mean concentration of non-biological aerosols was 442±99 μg/m3. The concentration of airborne fungal aerosol particles were lower than the World Health Organization guideline while the corresponding concentration of non-biological aerosols exceeded WHO limit. Most of the collected fungal particles were found in the inhalable size range (< 5μm) where inhalable fraction of fungi represents 84% of the total collected particles while inhalable fraction of non- biological aerosols represents 92% of the total collected particles. Size distributions of biological and non-biological aerosols were bimodal in nature. IED of fungi was 25.6 CFU/kg while the IED of non-biological aerosols was 37 CFU/kg
[en] Differential elastic scattering cross sections for Kaon K+ with proton p, neutron n, deuteron d and carbon 12C at an incident beam energy Lab. E<1 GeV (intermediate energy) were calculated in the eikonal approximation, and compared with experimental data over an angular range from (10-80) degrees. The semi-relativistic optical potentials of the kaon nucleon K+ N and kaon nucleus K+ A interactions were obtained and interpreted. On the basis of the One-Boson-Exchange (OBE) model, a set of boson parameters suggested by the Julich group were used to get the form of the interacting optical potential Vopt .(r ). In addition, the derived forms of the K+ A potential utilizing orbital density distribution of the nucleons in the target-nuclei (shell model), the relativistic effect of kaon beam were studied and found to play an important role. We have used the generalized Yukawa-type meson functions to evaluate the numerical results of the studied potentials.
[en] Studying structural analysis of nuclear fuel plates in research reactors is very important in design and safe operation conditions. Finite element packages are recently used to solve multi-physics problems. In this paper, fluid dynamic analysis is carried out in a Fluid-Structure Interaction (FSI) problem. Pressure distribution is obtained around the plate. The analysis is carried out for different velocities. The resulted pressure is then used as an input in structural analysis study. The deformation of the plate for different inlet velocities is obtained and compared to the calculated analogous work as well as the experimental results
[en] The current study presents a long-term light curve (LC) of the flat spectrum radio quasar (FSRQ) 4C +21.35 (also known as PKS 1222+216, z=0.432) as observed by the Fermi Large Area Telescope (LAT) during the first seven years of the mission with weekly time binning in the energy range 0.2-50 GeV. The highest weekly integral flux reached 2.647×10-6phcm-2s-1 on MJD = 55365 (2010 June 18). 4C +21.35 exhibited during this period two major flares (flare I during MJD = 55296-55405 and flare II during MJD = 56961-56984). For flare states, the variability of the source emission was studied with 12-hour time binning in two energy bands 0.2-0.8 GeV and 0.8-50 GeV. Three different statistical methods, the structure functions (SF), auto-correlation functions (ACF), and fast Fourier transformer (FFT) were used to study the time scales. For the seven year-weekly binning light curve, an 18-week time scale was observed. Flare I seems to have the same time scales for both energy ranges. Therefore, the outbursts during flare I may have come from the same emission mechanism/s; CCF between the two energy bands also emphasized it. Flare II did not give significant results. CCF illustrated a 6.5-day time lag that indicates the emission mechanism of the low energy band came before the high energy one with 6.5 day with a typical physical process
[en] Natural radionuclides of 238U ('226Ra), 232Th and 40K contained in the earth crust (soil) of Archaeological Site (Tanis, San Al-Hagar, Sharqai, Egypt) were measured using γ-ray spectroscopy system equipped with High pure germanium detector (HPGe). 20 soil samples were collected from the ground surface of tomb rooms, roads among tombs and the outer empty space of Tanis. Arithmetic mean values of radionuclides concentrations in the studied samples were 5.96 ± 1.46 Bq kg-1 for 226Ra, 3.78 ± 1.60 Bq kg-1 for 232Th and 70.34 ± 7.20 Bq kg-1 for 40K, respectively. All the studied natural radionuclides had concentration values less than worldwide recommended value of 35, 30, 400 Bq kg-1 for 226Ra, 23'2Th and 40K, respectively. Furthermore, the radiation dose in that site was measured using Digilert 100 radiation survey meter and its mean value was of 0.52 ± 0.13 μSv h-1 which is much lower than safety limit. Moreover, radiological hazards indices of radium equivalent activity (Raeq), external (Hex) and internal hazard indices (Hin), alpha and gamma radiation indices and annual effective dose due to the presence of those radionuclides were calculated and their values were less than worldwide limit. These results implied that the Tourists can safely visit and stay in this site (San Al-Hagar) as long as they wish.
[en] Region-of-interest (ROI) segmentation is an important critical step and challenging task in the evolution of computer-aided detection (CAD) system for breast cancer. The discovery of breast cancer in early stages can save many women lives. However, most of the early detection systems are costly in terms of complexity, price and processing time; that make it unsuited for developing countries.The digital mammography is proven to be one of the most important diagnostic techniques for breast cancer tumors. Therefore, this work proposes a CAD system for breast cancer detection from digital mammography based on Gaussian Mixture Model(GMM) followed by Support Vector Machine (SVM).The best contribution of our proposed system is the usage of GMM for the first time in the literature for mammogram images segmentation into ROI areas. Besides, the discrimination between the three classes of tissues as normal, benignor malignant, is used without previous knowledge of mammogram images’type. Moreover, the proposed system is fully automated in all of its stages with reduced computation compared with recent used methods. Hence, it offers a suitable early detection system to our country regarding money wise, time wise, and reduced complexity. A non-linear multi-class SVMis used for classifying the ROI into three classes: normal, benignor malignant tissue.The experiments show overall average classification accuracy of 90% for detecting normal, malignant or benignonrandomly chosen90 cases from the benchmark mini-MIAS dataset. On the other hand, the proposed method achieves 92.5% accuracy when classifying the benign from malignant cases. The confusion matrix was used to assess the proposed CAD system overall performance as it is considered to be a good evaluation metric method