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Modeling and Experiments of the Gain and Noise Figure for an Irradiated Erbium-Ytterbium Co-Doped Fiber Amplifier

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Journal of Analytical sciences, Methods and Instrumentation 2014年第2期4卷 53-61页

作者： sherif s. nafee Taymour A. Hamdalla Department of Physics Faculty of Science King Abdulaziz University Jeddah KSA Department of Physics Faculty of Science Tabuk University Tabuk KSA

It is crucial to study the effect of radiation on the fiber amplifier devices. In the present paper, the Erbium-ytterbium co-doped fiber amplifier (EYDFA) has been irradiated by a neutron beam of different doses for various exposure times from an Am-241/Be-9 neutron source. The gain and noise figure of the EYDFA have been calculated theoretically and recorded after and before the irradiation to test its performance under the effect of irradiation. In order to show the enhancement in the gain of the fiber amplifier devices, a comparison between the gain of the irradiated EYDFA and Erbium doped Fiber amplifier (EDFA) has been carried out. The calculated results by the proposed model are in good agreement with the experimental ones. It indicates that the gain of EYDFA deteriorates after being irradiated by a neutron dose. Moreover, the gain of irradiated EYDFA has been reduced to 13.8 dB at a dose of 720 Gy.

关键词： Erbium-Ytterbium Co-Doped Fiber Amplifier Americium/Beryllium-Neutron source Gain Deterioration

Modeling of UTsG in the Pressurized Water Reactor Using Accurate Formulae of Thermodynamic Properties

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Journal of Applied Mathematics and Physics 2021年第5期9卷 947-967页

作者： Amir M. Alramady sheikha Al-sharif sherif s. nafee Deanship of Graduate studies King Abdulaziz University Jeddah Kingdom of Saudi Arabia Physics Department Faculty of Science King Abdulaziz University Jeddah Kingdom of Saudi Arabia Physics Department Faculty of Science Alexandria University Alexandria Egypt

In nuclear power plants, steam generators are important parts. This paper introduces a U-tube steam generator (UTsG) model implemented completely using MATLAB environment. The UTsG consists of four regions: upward and downward primary regions, upward and downward metal tube regions, and secondary regions, which contain heat transfer region, steam separation region, and subcooled water region. Governing equations are derived by applying energy and mass conservation equations in all regions. Accurate functions that describe the relationships between thermodynamic properties of the saturated steam are introduced instead of interpolation method that is widely used. steady state and one transient case are presented as well.

关键词： UTsG Modeling steam Tables Thermodynamic Properties

Continuous hydrothermal synthesis of AlO(OH)nanorods as a clean flame retardant agent

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Particuology 2015年第5期13卷 66-71页

作者： sherif Elbasuney school of Chemical Engineering Military Technical College

Aluminum-oxide-hydroxide （AIOOH） is a clean and non-toxic flame retardant. There have been many trials for the fabrication of ultrafine AIOOH, Two main approaches exist for nano-AlOOH synthesis： reactive precipitation and batch hydrothermal synthesis, Both approaches are laborious and time consuming with poor control of particle morphology. We report on the novel continuous flow manufacture of AIOOH nanorods with controlled morphology （particle size and shape） by hydrothermal synthesis. AIOOH was harvested from its mother liquor （colloidal solution） using poly（acrylamide-co-acrylic acid） copolymer as a flocculating agent. The developed AIOOH shape and size, crystalline phase, thermal stability, and endothermic heat sink action were investigated by transmission electron microscopy, X-ray diffractome- try, thermogravimetric analysis, and differential scanning calorimetry, respectively. The phase transition of AlOOH to Al2O3 was demonstrated by conducting different X-ray diffractometry scans from 400 to 700℃. These results may provide an option for the continuous synthesis of nano-AIOOH as a clean and non-toxic flame retardant with excellent thermal stability. Consequently, enhanced flammability properties can be achieved at low solids loading.

关键词： Flame retardants Hydrated minerals Hydrothermal synthesis

Thermochemical Aspects of Activated Ammonium Perchlorates with superior Thermal stability,Decomposition Enthalpy,Propagation Index,and Decomposition Kinetic Parameters

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Journal of Thermal science 2021年第6期30卷 2196-2201页

作者： sherif Elbasuney M.Yehia sHUKRI Ismael sherif Farag AHMED saleh GHARIEB s.El-sayyad Head of Nanotechnology Research Center Military Technical College(MTC)Cairo 11646Egypt school of Chemical Engineering Military Technical College(MTC)Cairo 11646Egypt science and Technology Center of Excellence Cairo 11646Egypt Drug Radiation Research Department National Center for Radiation Research and Technology(NCRRT)Egyptian Atomic Energy Authority(EAEA)Cairo 11646Egypt

Ammonium perchlorate(AP)includes oxidizing and reducing elements on the same *** can act as an efficient oxidizer and mono-propellant as *** this study,AP experienced crystallographic phase change from orthorhombic centrosymmetric to non-centrosymmetric under controlled isothermal heat *** diffractograms confirmed this crystallographic phase *** thermal behaviour of activated AP had been investigated using *** AP demonstrated high chemical stability with an increase in endothermic phase transition enthalpy by 170%.The enthalpy of the subsequent two main exothermic decomposition reactions was increased by 250%.Whereas AP demonstrated total decomposition enthalpy of 733 J/g,activated AP showed 2614 J/*** AP can secure self-sustained response at a high *** index(combustion enthalpy/ignition temperature)was employed to assess self-sustained reaction *** AP demonstrated high propagation index of 8.7 compared with 2.5 for un-activated *** decomposition kinetic parameters had investigated using Kissinger and KAs *** AP showed an increase in activation energy by 89%using the Kissinger method;kinetic parameters using the KAs method were in good agreement with the Kissinger *** can have concluded that AP with novel kinetic decomposition parameters for enhanced safety storage and high combustion characteristics has evolved.

关键词： solid propellants oxidizers thermal behavior Kinetic parameters activation energy

Prediction of the Average Decay Heat per Fission for MOX Nuclear Fuel

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Journal of Applied Mathematics and Physics 2022年第3期10卷 887-899页

作者： Amir M. Alramady Hanan M. Barashed sherif s. nafee Deanship of Post Graduate studies King Abdelaziz University Jeddah Kingdom of Saudi Arabia Department of Physics Faculty of Science King Abdulaziz University Jeddah Kingdom of Saudi Arabia Department of Physics Faculty of Science Hadhramout University Mukalla Yemen Department of Physics Faculty of Science Alexandria University Alexandria Egypt

MIXED Oxide Nuclear fuel (MOX) contains both uranium and plutonium in oxidized form. It is important to calculate the nuclear decay heat due to the single thermal fission (fission due to 0.0235 eV neutron) for all fissile nuclei in the MOX fuels (Usup>235sup>, Pusup>239sup>, and Pusup>241sup>). These fissile nuclei are the main source of the decay heat in MOX fuel. Decay heat calculation of the weighted fissile material content in MOX fuel is also important. A numerical method was used in this work to calculate the concentrations of all fission products due to the individual thermal fission of the three fissile materials as a function of time N(t). The decay heat calculations for the three fissile materials are directly calculated using the summation method by knowing the different concentrations of fission products over time. The average decay heat of the MOX fuel in induced thermal fission is also concluded. The most influential nuclei in the decay heat were also identified. The method used has been validated by several comparisons before, but the new in this work is using the most recent Evaluated Nuclear Data Library ENDF/B-VIII.0. Calculations of decay heat show very common trends for a period of 10sup>7sup> sec after the fission burst of thermal fissions of individual fissile nuclei. Moreover, the code showed high capability in calculating the fission fragments inventories and decay heats due to the decay of fission fragments of 31 fissionable nuclei.

关键词： Nuclear Decay Heat Fission Burst Fission Fragments MOX Fuel MATLAB

Fission Fragment Decay Heat by Using the Most Recent Evaluated Nuclear Data Library ENDF/B-VIII

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Journal of Applied Mathematics and Physics 2022年第4期10卷 1182-1190页

作者： Amir M. Alramady Hanan M. Barashed sherif s. nafee Deanship of Post Graduate studies King Abdulaziz University Jeddah KSA Department of Physics Faculty of Science King Abdulaziz University Jeddah KSA Department of Physics Faculty of Science Hadhramout University Mukalla Yemen Department of Physics Faculty of Science Alexandria University Alexandria Egypt

In this paper, a home-made code was designed to calculate the decay heat emitted by fission fragments as a result of successive radioactive emissions after a fission burst. The nuclear data necessary for the calculations was extracted from the latest version of the Evaluated Nuclear Data Library ENDF/B-VIII.0. The code can calculate the decay heat of thermal and fast neutron-induced fission reactions on the isotopes of Thorium, Protactinium, Uranium, Neptunium, Plutonium, Americium, Curium, California, Einsteinium, and Fermium. A numerical method was used in this work to calculate the decay heat of all fission fragments due to the individual thermal or fast fissions of the isotopes of the previous ten actinides. The most influential nuclei in the decay heat were also identified at different times after the fission event. Moreover, the code showed high capability in calculating the fission fragments inventories and decay heats due to the decay of fission fragments of 31 fissionable nuclei.

关键词： Nuclear Decay Heat Fission Burst Fission Fragments MATLAB

Hyperspectral imaging and remote trace detection of cis-1,3,4,6-tetranitrooctahydroimidazo-[4,5 d]imidazole(BCHMX)compared with traditional explosives using laser induced fluorescence

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Defence Technology（防务技术） 2021年第5期17卷 1609-1616页

作者： Hany s.Ayoub Ashraf F.El-sherif Ahmed Elbeih Department of Physics Faculty of ScienceCairo UniversityEgypt Laser Photonics Research Center Engineering Physics DepartmentMilitary Technical CollegeCairoEgypt Explosives Department Military Technical CollegeKobry ElkobbahCairoEgypt

cis-1,3,4,6-Tetranitrooctahydroimidazo-[4,5 d]imidazole(BCHMX)is an advanced energetic compound that expected to spread worldwide in the near ***,no approved remote detection methods were reported in current literature for this material,we performed hyper-spectral imaging and laser induced fluorescence(LIF)to a BCHMX sample under low laser fluence for determining the optimum laser wavelength used in any future BCHMX-LIF based remote detection *** this purpose,an experimental setup consisted of a sun spectrum lamp and hyper-spectral camera was built to illuminate and image white powder samples of BCHMX in comparison with the traditional explosives,HMX(1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane),RDX(1,3,5-trinitro-1,3,5-triazacyclohexane),PETN(2,2-Bis[(nitroxy)methyl]propane-1,3-diyldinitrate).The imaging reveals strong BCHMX sample absorption contrast among other samples at wavelength ranging from 400 to 410 *** light source was replaced by a 405 nm laser diode illuminator,a strong BCHMX sample LIF at the spectral range from 425 to 700 nm was observed under low laser fluence condition of 0.1 mJ/cm^(2).Finally,we demonstrated successfully the ability of the 405 nm LIF and the hyperspectral imaging technique to detect finger print traces of BCHMX on white cellulose fabric from a distance of 15 m and a detection limit of 1 mg/cm^(2).

关键词： Hyperspectral imaging Remote trace detection BCHMX Laser induced fluorescence

Accurate Formulae for the Cross-section Data for the Radio-Halogen I-123 from Cyclotron Production

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Open Journal of Applied sciences 2023年第9期13卷 1489-1497页

作者： sherif s. nafee Amir M. Al-Ramady Manal F. Alshammari Physics Department Faculty of Science King Abdulaziz University Jeddah KSA Department of Nuclear Engineering Faculty of Engineering King Abdulaziz University Jeddah KSA Physics Department Faculty of Science University of Hail Hail KSA

123I is the most widely used cyclotron-produced radio-halogen in medical research. In this paper, excitation function formulae for the nuclear reactions of 123I production are introduced. 124Te (p, 2n)123I and 127I (p, 5n)123Xe → 123I nuclear reactions have been studied as a function of the energy of the neutrons. Both two formulae were created using the least squares regression of the experimental cross sections data, which were obtained from the Experimental Nuclear Reaction Data EXFOR Database version of 2023. The proposed formulae were evaluated using two statistical indicators for goodness-of-fit. High agreement was observed between the empirical and experimental results for both nuclear processes.

关键词： Cross section Radioisotope Production PET sPECT and Radio-Halogens

New design simulation for a high-altitude dual-balloon system to extend lifetime and improve floating performance

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Chinese Journal of Aeronautics 2018年第5期31卷 1109-1118页

作者： sherif sALEH Weiliang HE Aviation and Aerospace science Division Military Technical College school of Astronautics Beihang University

This paper presents a comprehensive simulation for a high-altitude dual-balloon system which consists of zero-and super-pressure balloons. Preliminary calculations were established to describe the basic concept of the new integrated system. A mathematical model was investigated to simulate the ascending and floating processes which considered the atmospheric conditions and thermodynamic variations. Based on the simulation, results showed that the floating altitude stability between daytime and nighttime was improved. This integrated system supports higher floating altitude levels than those of ordinary balloons and extends the lifetime of floating balloon systems. Moreover, results demonstrated that the integrated system was lighter than ordinary balloons, saving useful weight for effective payload. Furthermore, exploiting the advantages of both kinds of balloons while avoiding the difficulties was a significant goal in the current design to promote the floating performance of high-altitude balloons technology.

关键词： Altitude stability Ascending trajectory Compressor performance High altitude balloons Long endurance