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Water equivalence of some 3D dosimeters:a theoretical study based on the effective atomic number and effective fast neutron removal cross section

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Nuclear Science and Techniques 2017年第12期28卷 170-181页

作者： a.m.el-Khayatt Department of Physics College of Science Al Imam Mohammad Ibn Saud Islamic University (IMSIU) Reactor Physics Department NRC Atomic Energy Authority

Effective atomic numbers for photon energy absorption(ZPEA_(eff)) and their corresponding electron numbers (NPEA_(eff)), and effective macroscopic removal cross sections of fast neutrons(RR) were calculated for 27 different types of three-dimensional dosimeters, four types of phantom materials, and water. The values of ZPEA_(eff) and NPEA_(eff) were obtained using the direct method for energies ranging from 10 keV to 20 meV. Results are presented relative to water, for direct comparison over the range of examined energies. The effect of monomers that are used in polymer gel dosimeters on the water equivalence is discussed. The relation between Σ_R and hydrogen content was studied. micelle gel dosimeters are highly promising because our results demonstrate perfect matching between the effective atomic number, electron density number, and fast neutron attenuation coefficient of water.

关键词： 3D dosimeters Water equivalence Effective atomic number Photon energy absorption Removal cross section Fast neutrons

Combined effects of two sulfonylurea herbicides on soil microbial biomass and N-mineralization

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Journal of Environmental Sciences 2001年第3期13卷 311-317页

作者： a.m.el-Ghamry HUANG Chang-yong XU Jian-ming College of Natural Resources and Environmental Sciences Zhejiang UniversityHangzhou 310029China

The interaction effect of two sulfonylurea herbicides, bensulfuron methyl (B) and metsulfuron methyl(m), were tested on microbial biomass C, N, N mineralization and C/N ratio in a loamy sand soil. The herbicides were applied at various levels of: control (B0m0), 0.01 and 0.01 (B1m1), 0.01 and 0.1 (B1m2), and 0.01 and 1.0 (B1m3) μg/g soil. Determinations of soil microbial biomass C, N and N mineralization contents were carried out at 1, 3, 5, 7, 10, 15, 25 and 45 days after herbicides application. The results showed that the soil microbial biomass C (C mic ) and microbial biomass N (N mic ) decreased consistently with the increasing rates of herbicides. The results further indicated that B1m1 and B1m2 caused a significant reduction in C mic and N mic within first 10 and 7 days of incubation, respectively, as compared with the control. These reductions in C mic and N mic were also significant ( P =0.05) with B1m3 application especially within first 15 days of incubation. A significant reduction in N mineralization (N min) was observed with high doses (B1m2, B1m3) of herbicides within first 5 days of incubation, while low rate (B1m1) failed to produce any significant effect. An increase in the soil microbial biomass C:N ratio was also noted.

关键词： bensulfuron methyl metsulfuron methyl C mic N mic N mineralization loamy sand soil

electrical Conductivity and Sensitive Characteristics of Ag-Added BaTiO_3-CuO mixed Oxide for CO_2 Gas Sensing

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Journal of materials Science & Technology 2011年第1期27卷 35-40页

作者： a.m.el-Sayed F.m.Ismail S.m.Yakout Inorganic Chemistry Department National Research CentreTahrir StreetDokki P.C.12622 CairoEgypt

Carbon dioxide gas sensors based on BaTiO3-CuO composite with different concentrations of Ag addition（1,1.5 and 2 wt%） have been prepared by stander ceramic method and sintered at 500 and 700℃ for 5 *** conductivity and gas sensing properties of the prepared samples were *** conductivity measurement was used to characterize the obtained sintered sensor *** was found that electrical conductivity and the sensitivity to CO2 were improved with Ag addition and *** correlation between Ag content at different sintering temperature and sensing characteristics towards CO2 is discussed.

关键词： BaTiO3-CuO composite Ag addition electrical conductivity CO2 sensitive properties

On the Estimation of Solutions for Some Linear Systems of Differential Equations

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Acta mathematica Sinica,English Series 1998年第1期14卷 41-46页

作者： L. R. Awad E. m. el-Kholy Sh. el-bendary Universitat Hamburg Institut fur Angewandte mathematik Bundesstraβe 55 20146 Hamburg Germany

In this paper we estimate the solutions of homogeneous linear system of differential equations with unbounded coefficients on the real line R. We also give a necessary and sufficient condition in order that the linear... 详细信息

关键词： Homogeneous linear Unbounded coefficient

Propagation of electron Acoustic Soliton,Periodic and Shock Waves in Dissipative Plasma with a q-Nonextensive electron Velocity Distribution

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Communications in Theoretical Physics 2015年第11期64卷 529-536页

作者： a.m.el-Hanbaly E.K.el-Shewy A.elgarayhi A.I.Kassem Theoretical Physics Group Faculty of ScienceMansoura University Department of Physics Taibah University

The nonlinear properties of small amplitude electron-acoustic(EA) solitary and shock waves in a homogeneous system of unmagnetized collisionless plasma with nonextensive distribution for hot electrons have been investigated.A reductive perturbation method used to obtain the Kadomstev-Petviashvili-Burgers *** analysis has been discussed for non-dissipative system in the absence of Burgers term and reveals different classes of the traveling wave *** obtained solutions are related to periodic and soliton waves and their behavior are shown *** the presence of the Burgers term,the EXP-function method is used to solve the Kadomstev-Petviashvih-Burgers equation and the obtained solution is related to shock *** obtained results may be helpful in better conception of waves propagation in various space plasma environments as well as in inertial confinement fusion laboratory plasmas.

关键词： electron-acoustic solitary and shock waves reducti

Gamma-ray measurements of natural radioactivity in sedimentary rocks from Egypt

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Nuclear Science and Techniques 2006年第2期17卷 123-128页

作者： a.m.el-ARABI Adel G.E.ABBADY A.S.HUSSEIN Physics Department Faculty of Science South Valley University Qena Egypt Radiation Protection Department Nuclear Power Plants Authority Egypt

The aim of this study was to measure concentrations and distributions of natural radionuclides occurring in rocks. The activity concentrations (Bq·kg-1) of the naturally occurring radionuclides 226Ra, 232Th, and 40K in sedi- mentary rock samples from Eastern Desert (Um el-Huetat), Nile Valley (Gebel Owina) and from southwest Sinai (Wadi Ghweiba) were measured using a high-purity germanium detector. The samples under investigation (clay, shale and sandstone) were used as raw materials in the construction industry (bricks, ceramics, cement, fillers, etc.). Though the sediments of Egypt have already been investigated in the geological and mineralogical aspects, it is necessary to investigate the natural radioactivity in order to complete their classification. The average concentration values of 226Ra, 232Th, 40K in the surveyed samples were 47 ± 7 , 21± 5, 393±19 ***-1 (clay); 23 ± 5, 30 ± 6, 563 ± 24 ***-1 (shale); and 17 ± 4, 14 ± 4, 299 ± 17 ***-1 (sandstone), respectively. All sediment samples have radium equivalent activities ranging from 55 to 115 Bq·kg-1, lower than the limit set in the OECD Report (370 Bq·kg-1). The overall mean outdoor terrestrial gamma dose rates fluctuate from 28 to 55 nGy·h-1. The external gamma radiation dose due to natural radionuclides present in the samples have been computed and compared with the global averages. In terms of the radiation safety, the natural radioactivity of the sediment in Egypt is below the recommended limits of the gamma dose rate. Therefore, they can be used for all kinds of public buildings.

关键词：天然放射性核素页岩沙岩埃及

Nonlinear Dust Acoustic Waves in Dissipative Space Dusty Plasmas with Superthermal electrons and Nonextensive Ions

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Communications in Theoretical Physics 2016年第5期65卷 606-612页

作者： a.m.el-Hanbaly E.K.el-Shewy m.Sallah H.F.Darweesh Theoretical Physics Research Group Physics Department Faculty of Science Mansoura University Department of Physics Taibah University

The nonlinear characteristics of the dust acoustic(DA)waves are studied in a homogeneous,collisionless,unmagnetized,and dissipative dusty plasma composed of negatively charged dusty grains,superthermal electrons,and nonextensive *** pseudopotential technique has been employed to study the large amplitude DA ***(Sagdeev pseudopotential)has an evidence for the existence of compressive and rarefractive *** global features of the phase portrait are investigated to understand the possible types of solutions of the Sagdeev *** the other hand,the reductive perturbation technique has been used to study small amplitude DA waves and yields the Korteweg-de Vries-Burgers(Kd V-Burgers)equation that exhibits both soliton and shock *** behavior of the obtained results of both large and small amplitude is investigated graphically in terms of the plasma parameters like dust kinematic viscosity,superthermal and nonextensive parameters.

关键词： Sagdeev pseudopotential KdV-Burgers equation soliton and shock waves reductive perturbation dust kinematic viscosity

Natural ray-emitting radionuclides in Egyptian cement

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Nuclear Science and Techniques 2005年第6期16卷 376-380页

作者： a.m.el-ARABI A.ABBADY A.H. el-KAmel A. NOSIER A. mOUSTAFA Physics Deptartment Faculty of Science Qena South Valley University Egypt Physics Deptartment Faculty of Science Assiut University Egypt Physics Deptartment Faculty of Science El-Azhar University Egypt

Samples of cement manufactured in Egypt and the raw materials have been analyzed usinggamma-spectroscopy, in order to determine the concentration of natural radionuclides and associated radiologicalhazard. The mean of specific activity due to radionuclides of 226 Ra, 232 Th and 40 K was found to be (20±4), (11± 2),(320±18) (gypsum), (41±8), (27±5), (410±27) (clay), (58±11), (18±3), (321±20) (iron ore) and (37.6±6), (11.8±3),(178.6±15) Bq?kg -1 (Portland cement), respectively. 40 K concentration could not be detected in slag, limestone, sul-phateresistant cement (S.R.C.), clinker and white cement, while the mean specific activities of 226 Ra and 232 Th are(239±16), (48.7±7); (31.5±5), (10±2); (47±7), (20±5); (23±5), (10.4±3) and (23±5), (11±3) Bq?kg -1 , respectively. Theactivities (concentrations) are in the same range as the data released in other countries. The calculated radiation haz-ardparameters for all the samples are still lower than the acceptable values in Egypt and other countries.

关键词： γ射线放射性核埃及伽马射线

A Synergistic multi-Attribute Decision-making method for Educational Institutions Evaluation Using Similarity measures of Possibility Pythagorean Fuzzy Hypersoft Sets

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Computer modeling in Engineering & Sciences 2025年第1期142卷 501-530页

作者： Khuram Ali Khan Saba mubeen Ishfaq Atiqe Ur Rahman Salwa el-morsy Department of mathematics University of SargodhaSargodha40100Pakistan Department of mathematics University of Management and TechnologyLahore54000Pakistan Department of mathematics College of ScienceQassim UniversityBuraydah51452Saudi Arabia

Due to the numerous variables to take into account as well as the inherent ambiguity and uncertainty,evaluating educational institutions can be *** concept of a possibility Pythagorean fuzzy hypersoft set(pPyFHSS)is more flexible in this regard than other theoretical fuzzy set-like models,even though some attempts have been made in the literature to address such *** study investigates the elementary notions of pPyFHSS including its set-theoretic operations union,intersection,complement,OR-and *** results related to these operations are also modified for ***,the similarity measures between pPyFHSSs are formulated with the assistance of numerical examples and ***,an intelligent decision-assisted mechanism is developed with the proposal of a robust algorithm based on similarity measures for solving multi-attribute decision-making(mADm)problems.A case study that helps the decision-makers assess the best educational institution is discussed to validate the suggested *** algorithmic results are compared with the most pertinent model to evaluate the adaptability of pPyFHSS,as it generalizes the classical possibility fuzzy set-like theoretical ***,while considering significant evaluating factors,the flexibility of pPyFHSS is observed through structural comparison.

关键词： Hypersoft set Pythagorean fuzzy hypersoft set computational complexity multi-attribute decision-making optimization similarity measures uncertainty