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Calculation of photon shielding properties for som. neutron shielding m.terials

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Nuclear Science and Techniques 2017年第5期28卷 74-80页

作者： A. m. el-Khayatt Physics Departm.nt College of Science Al Imam Mohammad Ibn Saud Islamic University (IMSIU) RiyadhSaudi Arabia Reactor Physics Departm.nt NRC Atomic Energy Authority 13759 Cairo Egypt

The objective of the present study is to calculate photon shielding param.ters for seven polyethylene-based neutron shielding m.terials. The param.ters include the effective atom.c num.er(Z_(eff)), the effective electron density(N_(eff)) for photon interaction and photon energy absorption,and gam.a-ray kerm. coefficient(kc). The calculations of Z_(eff)are presented as a single-valued and are energy dependent. While Z_(eff)values were calculated via sim.listic powerlaw m.thod, the energy-dependent Z_(eff)for photon interaction(Z_(PI-eff)) and photon energy absorption(Z_(PEA-eff)) are obtained via the direct m.thod for energy ranges of 1 keV–100 GeV and 1 keV–20 m. V, respectively. The kccoefficients are calculated by sum.ing the contributions of the m.jor partial photon interactions for energy range of 1 keV–100 m.V. In m.st cases, data are presented relative to pure polyethylene to allow direct com.arison over a range of energy. The results show that com.ination of polyethylene with other elem.nts such as lithium.and alum.num.leads to neutron shielding m.terial with m.re ability to absorb neutron and crays. Also, the kerm. coefficient first increases with Z of the additive elem.nt at low photon energies and then converges with pure polyethylene at energies greater than 100 keV.

关键词： Neutron shielding m.terials Effective atom.c num.er Kerm. coefficient c-rays

Fault Diagnosis in Distribution Networks with Distributed Generation

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Sm.rt Grid and Renewable Energy 2011年第1期2卷 1-11页

作者： amany m. el-zonkoly 不详

The penetration of distributed generation (DG) in distribution power system.would affect the traditional fault current level and characteristics. Consequently, the traditional protection arrangem.nts developed in distribution utilities are difficult in coordination. Also, the reclosing schem. would be affected. With the rapid developm.nts in distribution system.autom.tion and com.unication technology, the protection coordination and reclosing schem. based on inform.tion exchange for distribution power system.can be realized flexibly. This paper proposes a m.lti-agent based schem. for fault diagnosis in power distribution networks with distributed generators. The relay agents are located such that the distribution network is divided into several sections. The relay agents m.asure the bus currents at which they are located such that it can detect and classify the fault, and determ.ne the fault location. The proposed technique uses the entropy of wavelet coefficients of the m.asured bus currents. The perform.nce of the proposed protection schem. is tested through sim.lation of two system.. The first system.is a benchm.rk m.dium.voltage (m.) distribution system.and the second system.is practical 66 kV system.of the city of Alexandria.

关键词： Cooperative System. Relay Agent Fault Diagnosis Distributed Generation Wavelet Transform Entropy Calculation

The com.ined effects of farm.yard m.nure and boron application on growth,and oil quality of Canola grown under newly reclaim.d soils

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Oil Crop Science 2024年第1期9卷 53-59页

作者： Farid Hellal Saied el Sayed amany Abdel m.hsen Ram.dan Doaa m.Abobasha Plant Nutrition Departm.nt National Research Centre33 El-Behouth St12622DokkiCairoEgypt Botany Departm.nt National Research Centre33 El-Behouth St12622DokkiCairoEgypt

Two field experim.nts were conducted during the m.in seasons of 2021/2022 at the Research and Production Station of National Research Centre in Egypt to investigate the effects of farm.ard m.nure(FYm.and boron on Canola growth,yield,oil yield,and *** results unequivocally dem.nstrated that the com.ined application of FYm.at a rate of 14.4 ton ha^(-1)with a foliar spray of boron at 100 ppm.positively influenced plant characteristics,leading to enhanced growth rates and higher yields com.ared to the control ***,this integrated approach significantly im.roved nutrient content by enhancing levels of oil content,carbohydrates,proteins,phenolics,flavonoids,and total soluble *** findings provide com.elling evidence that utilizing farm.m.nure along with boron can effectively enhance Canola properties in newly reclaim.d soils while prom.ting sustainable agricultural practices.

关键词： Oil quality Farm.ard m.nure Phytochem.cal content Canola Yield production

Thiolsulfonate functionalized polystyrene resin:Preparation and application in the isolation and identification of electrophilic m.tagens

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Journal of Environm.ntal Sciences 2007年第12期19卷 1520-1527页

作者： Wu el Robert m. Carlson Research Center for Eco-Environm.ntal Sciences Chinese Academy of Sciences Beijing 100085 China Departm.nt of Chem.stry University of Minnesota-Duluth Duluth MN 55812 USA

A new approach for isolation and identification of elecrtophilic m.tagens from.com.lex m.trix was developed. Thiosulforfic anion was im.obilized onto polystyrene beads and used as separation m.dia. Potassium.polystyryl-thiosulfonate, prepared from.polystyryl- sulfonyl chloride and KHS, was observed to selectively react with m.del electrophilic m.tagens such as alkyl halides, ct-chloroketones and α-chloroesters to produce polystyryl-thiosulfonlc esters. After separation from.other nonreactive organic com.ounds, the beads then reacted with ethanethiol to produce unsym.etrical ethyl disulfides which are easily detected by GC/m.. For one m.tagenic com.ound, only one unsym.etrical disulfide was found to contain its structure part. Thus, the structure of the parent m.tagens could be deduced from.that of the unsym.etrical disulfides. The degree of functionalization of the potassium.polystyryl-thiosulfonate resin was 1.11 m.ol/g. Its reactivity was discussed and its recycling m.thod was reported here.

关键词： functionalized polystyrene potassium.polystyryl-thiosulfonate unsym.etrical ethyl disulfides electrophilic m.tagens

Separation of rare earth elem.nts from.sulfate leach liquor by heterocyclic nitrogen com.ound

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Journal of Rare Earths 2008年第4期26卷 544-551页

作者： GHADA m. m.hm.ud NABIL T. el Hazek AHm.D m. Farag Om.EYA m. el Hussaini Nuclear m.terials Authority P.O. Box 530 El Maadi Cairo Egypt Chem.stry departm.nt Faculty of Science Cairo University Giza Egypt

Separation of rare earth dem.nts by solvent extraction has actually been widely used in various fields from.analytical chem.stry to hydrom.tallurgy. A representative ore sam.le obtained from.Kadabora Batholiths-Eastern Desert of Egypt, containing the m.ltiple oxides rare earth m.nerals： Sam.rskite, Fergusonite, Betafite, and Pyrochlore, was subjected to sulfuric acid leaching. Different sets of equilibrium.loading experim.nts were carded out on a bench scale for the extraction of rare earths （cerium.and yttrium. from.the sulfate leach liquor using 8,9-dihydro[1,2,4]triazolo[1,5-a]quinazolin-6（TH）-one {TQ} dissolved in m.thylene chloride. Stripping was carded out by 20% sodium.hydroxide. A rare earth cake was produced by oxalic acid precipitation. Its purity reached 87.3%.

关键词： triazolopyrim.dine extraction stripping precipitation rare earths

Extraction of niobium.from.sulfate leach liquor of Egyptian ore sam.le by triazoloquinazolinone

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中国有色金属学会会刊：英文版 2009年第2期19卷 474-478页

作者： O. m. el HUSSAINI Nuclear m.terials Authority P.O. Box 530 El MaadiCairoEgypt

The refractory niobium.bearing m.nerals,Sam.rskite,Fergusonite,Betafite and Pyrochlore of the ore sam.le obtained from.Kadabora,Egypt,was subjected to sulfuric acid leaching using acid concentrations varied from.17.6 to 4.5 m.l/ L. The extraction of niobium.from.the sulfate leach liquors was done using the synthesized 8,9-dihydro[1,2,4]triazolo[1,5-a]quinazolin6(7H)-one dissolved in m.thylene chloride. It has been found that extraction efficiency of 84% was achieved by contacting equal volum.s of 0.32% extractant with 4.5 m.l/L sulfate solution for 15 m.n. The stripping was perform.d by 0.5 m.l/L HF with efficiency of 86.7%.

关键词：硫酸浸出液矿石样品提取效率铌矿物埃及使用浓度二氯甲烷硫酸溶液

Topological m.del for recom.ination of DNA and RNA

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International Journal of Biom.them.tics 2018年第8期11卷 35-49页

作者： m. m. el-Sharkasy Departm.nt of m.them.tics Faculty of Science Tanta University Tanta Egypt sharkasy 78 @yahoo. com

The aim.of this paper is to use topological concepts in the construction of flexible m.them.tical m.dels in the field of biological m.them.tics. Also, we will build new topographic types to study recom.ination of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Finally, we study the topographical properties of constructed operators and the associated topological spaces of DNA and RNA.

关键词： Recom.ination DNA RNA topology closure lim.t point and connectedspace

Wavelet Entropy Based Algorithm.for Fault Detection and Classification in FACTS Com.ensated Transm.ssion Line

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Energy and Power Engineering 2011年第1期3卷 34-42页

作者： amany m. el-zonkoly Hussein Desouki 不详

Distance protection of transm.ssion lines including advanced flexible AC transm.ssion system.(FACTS) de-vices has been a very challenging task. FACTS devices of interest in this paper are static synchronous series com.ensators (SSSC) and unified power flow controller (UPFC). In this paper, a new algorithm.is proposed to detect and classify the fault and identify the fault position in a transm.ssion line with respect to a FACTS device placed in the m.dpoint of the transm.ssion line. Discrete wavelet transform.tion and wavelet entropy calculations are used to analyze during fault current and voltage signals of the com.ensated transm.ssion line. The proposed algorithm.is very sim.le and accurate in fault detection and classification. A variety of fault cases and sim.lation results are introduced to show the effectiveness of such algorithm.

关键词： FACTS SSSC UPFC Wavelet Transform Entropy Calculation

Geochem.stry of Late Cretaceous (60-67 m.) igneous activities in the Hebrides Terrace seam.unt (guyot) area, Scotland

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Chinese Journal Of Geochem.stry 2005年第1期24卷 9-17页

作者： m. el-Tokhi m. Om.an A. el-m.slem Geology Dept. Mansoura University Damietta 34517 EgyptGeology Dept. Mansoura University Damietta 34517 EgyptGeology Dept.United Arab Emirates University 17551 United Arab Emirates

Tholeiitic basalts in various stages of alteration were dredged from.Late Cretaceous volcanic rocks (60-67 m.) in the Hebrides Terrace seam.unt area in the Atlantic Ocean. These rocks are extrusive olivine basalts, including high- and low-Al basalts. High-Al basalts are depleted in m.O, CaO, Cr, Sc, V, Sr, Zr and enriched in TiO-2, Na-2O, Nb, Rb as com.ared with low-Al basalts. Petrography and bulk-rock com.osition (m.jor, trace and rare-earth elem.nts) data defined clear tholeiitic suites displaying possible liquid lines of descent related to different degrees of crystal fractionation and partial m.lting. Isotopic dating of dredged sam.les gave the guyot an age of 60-67 m., in support of the assum.tion that it was form.d during the Late Cretaceous.

关键词：地球化学白垩纪硅采样标准火成活性苏格兰