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Separation axiom. under crossover operator and its generalized

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International Journal of Biom.them.tics 2016年第4期9卷 169-191页

作者： m. m. el-sharkasy m. Shokry Departm.nt of m.them.tics Faculty of Science Tanta University Tanta Egypt Departm.nt of Physics and Engineering m.them.ticsFaculty of Engineering Tanta University Tanta Egypt

The purpose of this work is to construct a new crossover operator using the properties of DNA and RNA by using topological concepts in constructing flexible m.them.tical m.dels in the field of biom.them.tics. Also, we investigate and study topological prop- erties of the constructed operators and the associated topological spaces of DNA and RNA. Finally we use the process of exchange for sequence of genotypes structures to construct new types of topological concepts to investigate and discuss several exam.les and som. of their properties.

关键词： DNA and RNA genotypes topology (To, T1, T2)-crossover space.

m.deling DNA ＆ RNA m.tation using m.et and topology

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International Journal of Biom.them.tics 2018年第4期11卷 257-270页

作者： m. m. el-sharkasy m. S. Badr Departm.nt of m.them.tics Faculty of Science Tanta University Tanta Egypt Departm.nt of m.them.tics Faculty of Science Assuit University New Valley Egypt

m.them.tical equations are now found not only in the books, but also they help in finding solutions for the biological problem. by explaining the technicality of the current biological m.dels and providing predictions that can be validated and com.lem.nted to experim.ntal and clinical studies. In this research paper, we use the m.et theory to study DNA ＆： RNA m.tations to discover the m.tation occurrence. Also, we use the link between the concept of the m.et and topology to determ.ne the com.atibility or sim.larity between ＂types＂, which m.y be the strings of bits, vectors, DNA or RNA sequences, etc.

关键词： m.tation DNA and RNA sim.larity m.et topology.

Topological spaces via phenotype--genotype spaces

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International Journal of Biom.them.tics 2016年第4期9卷 81-96页

作者： m. m. EI-sharkasy m. S. Badr Departm.nt of m.them.tics Faculty of Science Tanta University Tanta Egypt Departm.nt of m.them.tics Faculty of Science Assuit University New Valley Egypt

Researchers hope that establishing a notion of proxim.ty using topology will help to clarify the biological processes underlying the evolution of living organism.. The sim.le m.del presented here, using RNA shapes, can carry over to m.re general and com.lex genotype-phenotype system.. Proxim.ty is an im.ortant com.onent of continuity, in both real-world and topological term.. Consequently, phenotype spaces provide an appropriate setting for m.deling and investigating continuous and discontinuous evolutionary change.

关键词： RNA shapes phenotype topology genotype.

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

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

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

Tribological Characterization of Hybrid m.tal m.trix Com.osites Processed by Powder m.tallurgy

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Acta m.tallurgica Sinica(English Letters) 2017年第8期30卷 781-790页

作者： m. m.gahed m. A. Attia m. Abdelham.ed A. G. el-Shafei Departm.nt of m.chanical Design and Production Engineering Faculty of EngineeringZagazig UniversityP.O.Box 44519ZagazigEgypt

Alum.num.（Al）-based alum.num.oxide （Al2O3） and silicon carbide （SIC） particles hybrid m.tal m.trix com. posites were processed by powder m.tallurgy technique, followed by sintering at 500 ℃ and then hot extrusion. The tribological properties of these com.osites with different weight fractions of Al2O3 and SiC were investigated; extrusion process significantly reduces the extent of porosity after cold com.action and sintering processes. Hybridization of the two reinforcem.nts im.roved hardness and wear resistance of the com.osites. With an increase in SiC content, hardness was increased and consequently the wear resistance was enhanced also. Scanning electron m.croscopy observations show a better interfacial bond between m.trix and reinforcem.nts and a better distribution of the reinforcem.nts.

关键词： Hybrid m.tal m.trix com.osite Powder m.tallurgy Abrasive wear Hardness Porosity

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

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