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radionuclides measurements and mineralogical studies on beach sands, East rosetta Estuary, Egypt

Chinese Journal Of Geochemistry 2013年第2期32卷 146-156页

作者： Abd el Wahab m. el Nahas H.A. Physics Department Faculty of Women for Arts Science and Education Ain Shams University Cairo P.O 11757 Egypt Nuclear materials Authority Cairo P.O. Box 530 Egypt

radiometric measurements were carried out for the beach sands from East rosetta estuary to determine the activity concentrations of 238 U, 226 ra, 232 Th, and 40 K, using a Hyper Pure Germanium spectrometer, to estimate the dose rates and radiation hazard indices. The average specific activities are 778.20 Bq/kg for 238 U; 646.89 Bq/kg for 226 ra; 621.92 and 627.85 Bq/kg for the 222 rn daughters 214 Pb and 214 Bi respectively. The average specific activity of 232 Th is 1510.25 Bq/kg, while the calculated specific activity for 40 K has an average of 8.41 Bq/kg. The average specific activity of 235 U is 38.61 Bq/kg. The average absorbed dose rate is 1211.36 nGy/h, 20 times higher than the estimated average global primordial radiation of 60 nGy/h and 6 times higher than that of the world range (10-200 nGy/h). The radium equivalent (ra eq ) values are from 6 to 9 times the recommended value. The internal and external hazard indices (H int , H ex ) indicate that their values are from 6 to 11 times the permissible values of these indices. These higher values may be due to the presence of economic heavy minerals containing radionuclides as zircon and monazite as well as some trace minerals, thorite and uranothorite. The mineralogical study indicates the beach sands contain heavy minerals, zircon, monazite, rutile, ilmenite, leucoxene, magnetite and garnet. The average abundance of zircon is 0.175 wt% ranging from 0.125 wt% to 0.239 wt%, while it is 0.004wt% ranging from 0.001 wt% to 0.007 wt% for monazite. The average abundance is 0.087 wt% for rutile; 2.029 wt% for ilmenite; 1.084 wt% for magnetite; 0.384 wt% for leucoxene and 0.295 wt% for garnet.

关键词：放射性核素海滩砂矿物学核素测量河口平均丰度埃及辐射测量

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Clinicobiochemical investigations of gangrenous mastitis in does:immunological responses and oxidative stress biomarkers

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第1期14卷 33-39页

作者： Wael m.el-DEEB Department of Clinical Studies College of Veterinary Medicine and Animal ResourcesKing Faisal University Department of Veterinary medicine Infectious Diseases and Fish DiseasesFaculty of Veterinary MedicineMansoura University

A total of 50 does were used to determine selected hematological and biochemical parameters with special references to oxidative stress markers, acute phase protein profiles, and proinflammatory cytokines in healthy and gangrenous mastitis affected does. Animals were divided into two equal groups represented as clinically healthy （control） and diseased groups, respectively. The bacteriological examination of milk samples from diseased does revealed many types of bacterial infection. The isolated bacteria were Staphy/ococcus aureus （N=23/25）, Escherichia coil （N=11/25）, and Clostridium perfringens （N=4/25）. There was a significant increase in the levels of β-hydrexybutyrate, non-esterified free fatty acids, triglyceride, low density lipoprotein cholesterol （LDL-C）, aspartate aminotransferase, and alanine aminotransferase and a significant reduction in the levels of glucose, cholesterol, and high density lipoprotein cholesterol （HDL-C） in does with gangrenous mastitis compared to healthy does. moreover, there was a significant increase in the levels of malondialdehyde and uric acid with a significant decrease in the levels of reduced glutathione, super oxide dismutase, and catalase in does with gangrenous mastitis compared to healthy does. In addition, there was a significant increase in the haptoglobin, serum amyloid A, fibrinogen, interleukin 6 （IL-6）, IL-1β, and tumor necrosis factor-a （TNF-a） in does with gangrenous mastitis compared to healthy ones. Conclusively, oxidative stress biomarkers, acute phase proteins, and proinflammatory cytokines play an essential task as biomarkers for gangrenous mastitis in does. mastitis may be considered as one of the ketotic stressors in does after parturition.

关键词： Haptoglobin Serum amyloid A malondialdehyde Interleukin 1β Interleukin 6 Tumor necrosis factor-a

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Alumina Effect on the Phase Transformation of 3Y-TZP Ceramics

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Journal of materials Science & Technology 2008年第6期24卷 873-877页

作者： Ezzat S.elshazly m.el-Sayed Ali S.m.el-Hout Department of metallurgy Nuclear Research CenterAtomic Energy AuthorityCairoEgypt

The isothermal tetragonal-to-monoclinic phase transformation of 3 mol fraction Y2O3-ZrO2 ceramics contain- ing different amounts of Al2O3 during ageing in water at 130℃ for periods of time up to 40 h was investigated to explore the effect of Al2O3 addition on this transformation. The propagation of the transformation into the specimen interiors was suppressed by the addition of Al2O3. The transformation kinetics showed a nucleation and growth mechanism on the specimen surface to be dominant in the low temperature ageing in water environment.

关键词： Phase transformation 3Y-TZP Al2O3 Kinetics

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Enhancing optical absorption in visible light of ZnO co-doped with europium and promethium by first-principles study through modified Becke and Johnson potential scheme

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Journal of rare Earths 2019年第4期37卷 416-421页

作者： A.G.el Hachimi m.L.Ould NE A.el Yousfi A.Benyoussef A.el Kenz Laboratory of Condensed matter and Interdisciplinary Sciences (LamCScI) Associé Au CNRST (URAC 12) Département de Physique B.P.1014 Faculté des SciencesUniversité Mohammed V Hassan Ⅱ Academy of Science and Technology

By using first-principles calculations we studied the electronic, optical and magnetic properties of ZnO co-doped with Eu and Pm. In this calculation, we used Wien2 k code based on full potential linearized augmented plane waves(FP-LAPW) method with the modified Becke-Johnson(mBJ) approximation. This correction gives good band gap compared to experimental band gap. The introduction of Eu and Pm codoping leads to an increase in the band gap. electrons can transit easily from the valence band to the conduction band, which results in an enhancement of visible light absorption in a wider absorption range. Absorption spectra reach a high value in visible and infrared light regions. With the significance of the obtained results, the studied compounds may potentially find spintronic and optoelectronic applications.

关键词： Zinc oxide rare earth Density functional theory modified Becke-Johnson magnetic properties Spintronics

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Isotherm and kinetic studies on the adsorption of humic acid molecular size fractions onto clay minerals

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Acta Geochimica 2019年第6期38卷 863-871页

作者： mohamed E.A.el-Sayed moustafa m.r.Khalaf James A.rice Department of Chemistry and Biochemistry South Dakota State UniversityBrookingsSD 57007USA Soils Waterand Environmental Research InstituteAgriculture Research CenterEl-GizaEgypt Chemistry Department Faculty of ScienceMinia UniversityEl-Minia 61519Egypt

Humic acid(HA)can adsorb onto mineral surfaces,modifying the physicochemical properties of the ***,understanding the sorption behavior of HA onto mineral surfaces is of particular interest,since the fate and transport of many organic and inorganic contaminants are highly correlated to HA adsorbed onto clay *** to the extreme heterogeneity of HA,the extracted IHSS Leonardite humic acid(LHA)used in this work was fractionated using an ultrafiltration technique(UF)into different molecular size fractions(Fr1,>0.2μm;Fr2,0.2 pm-300,000 daltons;Fr3,300,000-50,000 daltons;Fr4,50,000-10,000 daltons;Fr5,10,000-1000 daltons).Equilibrium and the kinetics of LHA and fraction adsorption onto kaolinite and montmorillonite were *** results demonstrated that the maximum adsorption capacity of LHA,Frl,Fr2,Fr3,Fr4,and Fr5 was 5.99,13.69,10.29,7.02,5.9&and 5.09 on kaolinite while it was 8.29,22.62,13.17,8.91,8.62,and 5.69 on montmorillonite,*** adsorption equilibrium data showed that the adsorption behavior of LHA and its fractions could be described more practically by the Langmuir model than the Freundlich *** rate of humic acid fraction adsorption onto clays increased with decreasing molecular size fraction and increasing carboxylic group ***-first-and second-order models were used to assess the kinetic data and the rate *** results explained that LHA and its fractions adsorption on clay minerals conformed more to pseudosecondo rder.

关键词： Kaolinite montmorillonite Leonardite humic acid Humic acid fractions Kinetics Equilibrium

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Extraction of niobium from sulfate leach liquor of Egyptian ore sample 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 materials Authority P.O. Box 530 El MaadiCairoEgypt

The refractory niobium bearing minerals,Samarskite,Fergusonite,Betafite and Pyrochlore of the ore sample obtained from Kadabora,Egypt,was subjected to sulfuric acid leaching using acid concentrations varied from 17.6 to 4.5 mol/ 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 methylene chloride. It has been found that extraction efficiency of 84% was achieved by contacting equal volumes of 0.32% extractant with 4.5 mol/L sulfate solution for 15 min. The stripping was performed by 0.5 mol/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

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Dynamic response of Composite materials with 2D reduced micromorphic model

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Acta mechanica Solida Sinica 2022年第4期35卷 603-615页

作者： A.r.el Dhaba C.W.Lim Department of mathematics Faculty of ScienceDamanhour UniversityDamanhourEgypt Department of Architecture and Civil Engineering City University of Hong KongKowloonHong Kong SARChina

In this article,we introduce a complete set of constitutive relations and field equations for the linear reduced micromorphic *** further investigate the internal variables and their relationship in the case of two-dimensional(2D)wave *** dynamic response is investigated for composite materials,which is due to an external wave in two dimensions applied at the boundary of the considered *** solutions for the model are unavailable at this stage due to dependency of the field equations on spatial and time variables in a complicated manner.A finite element approach is adopted to derive approximate solutions for the field equations,and numerical finite element solutions for the internal fields are presented in detail and discussed.

关键词： Composite materials Finite element method(FEm) reduced micromorphic model Wave propagation

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Separation of rare earth elements from sulfate leach liquor by heterocyclic nitrogen compound

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

作者： GHADA m. mahmoud NABIL T. el Hazek AHmAD m. Farag OmNEYA m. el Hussaini Nuclear materials Authority P.O. Box 530 El Maadi Cairo Egypt Chemistry department Faculty of Science Cairo University Giza Egypt

Separation of rare earth dements by solvent extraction has actually been widely used in various fields from analytical chemistry to hydrometallurgy. A representative ore sample obtained from Kadabora Batholiths-Eastern Desert of Egypt, containing the multiple oxides rare earth minerals： Samarskite, Fergusonite, Betafite, and Pyrochlore, was subjected to sulfuric acid leaching. Different sets of equilibrium loading experiments 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 methylene 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： triazolopyrimidine extraction stripping precipitation rare earths

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Amination of biochar surface from watermelon peel for toxic chromium removal enhancement

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Chinese Journal of Chemical Engineering 2021年第8期34卷 199-222页

作者： mohamed A.el-Nemr Ibrahim m.A.Ismail Nabil m.Abdelmonem Ahmed el Nemr Safaa ragab Department of Chemical Engineering Faculty of EngineeringCairo UniversityGizaEgypt renewable Energy Program Zewail City of Science and TechnologyEgypt Environmental Division National Institute of Oceanography and FisheriesKayet BeyEl-AnfoushyAlexandriaEgypt

Watermelon peel residues were used to produce a new biochar by dehydration *** new biochar has undergone two methods of chemical modification and the effect of this chemical modification on its ability to adsorb Cr(VI)ions from aqueous solution has been *** biochars,melon-B,melon-BO-NH_(2) and melon-BO-TETA,were made from watermelon peel via dehydration with 50%sulfuric acid to give melon-B followed by oxidation with ozone and amination using ammonium hydroxide to give melon-BO-NH_(2) or Triethylenetetramine(TETA)to give *** prepared biochars were characterized by BET,BJH,SEm,FT-Ir,TGA,DSC and EDAX *** highest removal percentage of Cr(VI)ions was 69%for melon-B,98%for melon-BO-NH_(2) and 99%for melon-BO-TETA biochars of 100 mg·L^(−1) Cr(VI)ions initial concentration and 1.0 g·L^(−1) adsorbents *** unmodified biochar(melon-B)and modified biochars(melon-BO-NH_(2) and melon-BO-TETA)had maximum adsorption capacities(Q_(m))of 72.46,123.46,and 333.33 mg·g^(−1),*** amination of biochar reduced the pore size of modified biochar,whereas the surface area was *** obtained data of isotherm models were tested using different error function *** Freundlich,Tempkin and Langmuir isotherm models were best fitted to the experimental data of melon-B,melon-BO-NH_(2) and melon-BO-TETA,*** adsorption rate was primarily controlled by pseudo-second–order rate ***,the functional groups interactions are important for adsorption mechanisms and expected to control the adsorption *** adsorption for the melon-B,melon-BO-NH_(2) and melon-BO-TETA could be explained for acid–base interaction and hydrogen bonding interaction.

关键词： Waste treatment Powder technology Citrullus lanatus Hexavalent chromium Biochar amination Adsorption

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Fluoride distribution and the effect of some ions along Alexandria coastal mediterranean seawater of Egypt

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Journal of Environmental Sciences 2003年第5期15卷 639-646页

作者： W.m.el-Sarraf m.S.masoud A.A.Harfoush GH.F.el-Said NationalInstituteofOceanographyandFisheries ChemistryDepartmentChemistryDepartmentNationalInstituteofOceanographyandFisheries AlexandriaEgyptFacultyofScienceAlexandriaUniversityEgyptFacultyofScienceAlexandriaUniversityEgyptAlexandriaEgypt

The coastal seawater of mediterranean of Alexandria receives large amount of discharged waters containing industrial wastes, sewage, and agricultural and domestic drainage. Fluoride and some parameters were(chemical and physical) determined. The data gave indication that the content and the amount of the discharged water largely affect the chemical composition of the coastal water. Stepwise regression analysis was highly significant and the model was very fruitful, where the observed and calculated values were mostly concordant. This may indicated that there was a relation between fluoride content in coastal seawater and its content in the discharged water.

关键词： fluoride distibution Alexandria costal mediterranean Egypt physical and chemical parametrs regression analysis

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