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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

in situ strength of coal bed based on the size effect study on the uniaxial compressive strength

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international Journal of mining Science and Technology 2014年第6期24卷 747-754页

作者： Gonzatti C. Zorzi L. Agostini i.m. Fiorentini J.A. Viero A.P. Philipp R.P. Department of mineralogy and Petrography of the Federal University of Rio Grande do Sul Brazil Foundation for Science and Technology of Rio Grande do Sul State Brazil

in the early 1990 s, the Foundation for Science and Technology of Rio Grande do Sul State(CiENTEC)developed a pioneering study in Brazil, related to the simultaneous mining of multiple coal *** of the activities included detailed studies on the geomechanical characterization of materials present in the irapua coal seam, under exploitation in the A-Sangao mine, located near the city of Crici.m.-SC,within the South-Catarinense coalfield. The goal of the laboratory tests was to define the behavior of the uniaxial compressive strength of the irapua coal seam and establish a first approximation for the in situ strength value of this coal seam, since existing knowledge is solely based on practical mining experience over the years. Large samples of the coal seam were collected, using special techniques to maintain the integrity of the material, and a set of 56 uniaxial compression tests in cubic specimens, with side length ranging from 4.5 to 31 cm, were conducted in laboratory. This paper describes the experimental techniques used in the assays, and also presents the uniaxial compression strength results ***, important aspects of this type of study are considered, highlighting the size effect for the carbonaceous bed and the estimation of in situ strength values for the irapua coal seam.

关键词： Size effect in situ strength Coal seam lrapua

Extraction of niobi.m.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 niobi.m.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 niobi.m.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

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 equilibri.m.loading experiments were carded out on a bench scale for the extraction of rare earths （ceri.m.and yttri.m. 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% sodi.m.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

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

Amination of biochar surface from watermelon peel for toxic chromi.m.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.i.m.il 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 ammoni.m.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 mechani.m. 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

Forensic toxicological study on adipocere formation in submerged cadavers of female albino rats intoxicated with cadmium

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Forensic Sciences Research 2021年第2期6卷 159-167页

作者： Nabela i.el-Sharkawy Yasmina m.Abd-elhakim Alklech m.Alklech Department of Forensic medicine and Toxicology Faculty of Veterinary MedicineZagazig UniversityZagazigEgypt

There is a dearth of information on the mutual interaction between metal intoxication and adipocere ***,40 adult female albino rats were distributed into two equal groups,one used as control while the other orally administered single dose of cadmi.m.chloride(CdCl_(2))225mg/kg·bw(LD_(min)).Control group was killed by cervical *** of dead rats of both groups were subjected for determination of iodine value and estimation of cadmi.m.Cd)residues while the other half of both groups were submerged in opened glass container previously filled with 4L dechlorinated tap water kept in closed room with an open air access(one cadaver/container).Gross morphological changes of submerged cadavers were recorded weekly along the *** the end of the experiment,after 3months,samples were collected again for iodine value determination and estimation of Cd *** obtained results revealed the depressant effect of Cd toxicity on development of *** residues were found in different tissues of cadavers at time of death with the highest amount in the intestines followed by the liver and kidneys,then lungs,adipose tissue,muscles,and finally the *** 3months of water submersion,tissues exhibited significant decrease in the amount of Cd residues but to a limit that was still *** study concluded the possibility of detection of Cd residues even after adipocere ***,it shed light on the possibility of the interference of environmental pollution with the natural rate of decomposition especially adipocere formation.

关键词： Forensic sciences forensic toxicology adipocere cadmium submersion rats

Adsorption properties of Rosmarinus officinalis oil as green corrosion inhibitors on C38 steel in 0.5 m H_2SO_4

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Acta metallurgica Sinica(English Letters) 2010年第1期23卷 13-20页

作者： E.el Ouariachi J.Paolini.m.Bouklah A.elidrissi A.Bouyanzer B.Hammouti J-m.Desjobert J.Costa Laboratoire de Chimie Appliqu'ee et Environnement Facult'e des SciencesUniversit'e Mohamed PremierBP71760000 OujdaMorocco UmR CNRS 6134 Laboratoire de Chimie des Produits NaturelsUniversit'e de CorseFrance

Rosmarinus officinalis essential oil obtained by hydrodistillation was tested as corrosion inhibitor of steel in 0.5 m H2SO4 using weight loss measurements, and electrochemical .polarisation methods. Results obtained indicate that the corrosion rate is reduced and R. officinalis oil adsorbs on the metal surface and then inhibits corrosion process. its inhibition efficiency increases with oil increasing content to reach 61% at 1 g/L. Polarisation curves indicate that RO acts as a cathodic inhibitor. The inhibition efficiency of naturally oil remains slightly constant with the rise of temperature. Chemical analysis of R. officinalis essential oil was carried out using capillary GC and GC/mS. The oil composition was characterized by high amount of oxygenated monoterpene （77%） with 1,8-cineol （52.1%） as main component. Discussion of adsorption was investigated on the the isotherm adsorption of essential oil on basis of essential oil composition. Finally the steel has been also reported.

关键词： Rosmarinus officinalis oil Adsorption Corrosion inhibition Steel 1,8-cineol

Study of Three Different Types of Plasma ion Sources

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Plasma Science and Technology 2009年第5期11卷 604-608页

作者： m.m.ABDelRAHmAN H.el-KHABEARy Accelerators & ion Sources Department Nuclear Research CenterAtomic Energy Authority

Three types of plasma ion sources designed, manufactured and optimized in the Accelerators and ion Sources Department, Nuclear Research Center, Atomic Energy Authority are introduced. Different means were investigated to generate the discharge current and ion beam current extracted from the plasma. The various plasmas described include a DC glow discharge plasma, an arc discharge plasma and a radio frequency discharge plasma.

关键词： ion sources ionization processes sputtering and etching processes

Vibrational, rotational, and triaxiality features in extended O(6) dynamical symmetry of i.m.using three-body interactions

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Nuclear Science and Techniques 2020年第5期31卷 44-56页

作者： A.m.Khalaf Azza O.el-Shal m.m.Taha m.A.el-Sayed Physics Department Faculty of ScienceAl-Azhar UniversityCairoEgypt mathematics and Theoretical Physics Department Nuclear Research CenterAtomic Energy AuthorityCairo 13759Egypt

The shape transition between the vibrational U(5)and deformed c-unstable O(6)dynamical symmetries of sd interacting boson model has been investigated by considering a modified O(6)Hamiltonian,providing that the coefficients of the Casimir operator of O(5)are N-dependent,where N is the total number of *** modified O(6)Hamiltonian does not contain the number operator of the d boson,which is responsible for the vibrational *** addition,the deformation features can be achieved without using the SU(3)limit by adding to the O(6)dynamical symmetry the three-body interaction[QQQ]^(0),where Q is the O(6)symmetric quadrupole ***,triaxiality can be generated through the inclusion of the cubic d-boson interaction[d+d+d+]^(3)·∣ddd∣^(3).The classical limit of the potential energy surface(PES),which represents the expected value of the total Hamiltonian in a coherent state,is studied and *** modified O(6)model is applied to the even–even^124-132 Xe *** parameters for the Hamiltonian and the PESs are calculated using a simulated search program to obtain the minimum root mean square deviation between the calculated and experimental excitation energies and B(E2)values for a number of low-lying levels.A good agreement between the calculations and experiment results is found.

关键词： Nuclear structure Extended O(6)of iBm Three-body interactions Coherent state