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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

Physical Studies of Some Hydrazinobenzoic Acid Complexes

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Journal of Materials Science & Technology 2005年第1期21卷 140-144页

作者： M.g.Abd el Wahed S.Abd el Wanees M.el gamel S.Abd el Haleem Faculty of Science Zagazig University Zagazig EgyptFaculty of Science Zagazig University Zagazig EgyptFaculty of Science Zagazig University Zagazig EgyptFaculty of Science Zagazig University Zagazig Egypt

The stability constants of complexes of 2-hydrazinobenzoic acid and 4-hydrazinobenzoic acid with Ni (Ⅱ), Cu (Ⅱ), Zn (Ⅱ), Cd (Ⅱ), and Hg (Ⅱ) were determined potentiometricaIly at different temperatures. The thermodynamic parameters, △g0, △H0, and △S0 were calculated and proved that the complexation process is spontaneous and endothermic. The thermodynamic functions were analyzed in terms of electrostatic and non-electrostatic components and the results reveal that ionic bonds are formed between the studied ligands and metal ions. Conductometric titration was shown that the stoichiometry of the formed complexes are M:L and M:2L. The structure of the prepared solid complexes was characterized using IR, 1H NMR, 13C NMR spectroscopies as well as X-ray diffraction technique. Finally electrical conductivity of the ligands and their copper complexes was measured and shown that the ligands have a semiconductor behaviour.

关键词： Potentiometric titration Stability constants Thermodynamic parameters Structure of metal complexes

沉积成因Sr/Ba指示的福建潮控海湾全新世沉积环境及海平面意义

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海洋地质与第四纪地质 2024年第5期44卷 95-106页

作者：陈能邱彬焕张杰余欢刘演 el Said Shetaia 孙千里于俊杰陈静华东师范大学河口海岸学国家重点实验室上海200241 华东师范大学地理科学学院上海200241 中国地质调查局南京地质调查中心南京210016

福建沿海多发育潮控型海湾,潮滩平坦宽广,海湾水深较浅,有孔虫等微体生物较为匮乏,且其化石在地层中保存相对较差,致使沉积微相辨识存在一定难度,从而限制了深入理解该区全新世海平面变化过程及沉积环境响应。本研究拟利用不受保存环境... 详细信息

福建沿海多发育潮控型海湾,潮滩平坦宽广,海湾水深较浅,有孔虫等微体生物较为匮乏,且其化石在地层中保存相对较差,致使沉积微相辨识存在一定难度,从而限制了深入理解该区全新世海平面变化过程及沉积环境响应。本研究拟利用不受保存环境限制的沉积成因Sr/Ba指标,探索其在福建宁德三沙湾地区沉积微相的辨识潜力,并结合AMS 14C年龄,探讨该区全新世以来的沉积环境演化及区域海平面变化。结果表明:①沉积成因Sr/Ba在三沙湾潮滩和海湾表层沉积物中平均值分别为9.06和20.43,具有显著差异。潮滩沉积物中的Sr/Ba明显高于长江等大河口地区(1~3),这是该区淡水输入量较少、潮滩盐度较高所致,这说明该指标辨识海陆过渡沉积相时需要考虑区域水文特点。②晚第四纪NDgK2钻孔沉积物Sr/Ba自下而上可分为3层(Ⅰ—Ⅲ):层Ⅰ为杂色硬黏土,Sr/Ba比值全孔最低(均值5.29),但也高于淡水环境,推测为前期海相沉积物的暴露改造;层Ⅱ—Ⅲ均为深灰色黏土,其中层Ⅱ均值为10.77,接近潮滩相;层Ⅲ均值为全孔最高(13.44),接近海湾相。结合AMS 14C年龄可知,NDgK2钻孔的河漫滩-潮滩-海湾沉积相演化受控于全新世海平面上升过程,潮滩相形成于约8.9 ***,当时该区海平面大约在−21.0±2.5 m,最大海泛面出现于约8.2 ***,之后出现了长达6 ka的低沉积速率时期,直至约2.2 ***海湾内加速沉积。③该区15个钻孔全新统底部Sr/Ba均显现出明显的潮滩相特征,这为重建区域全新世相对海平面提供了可行性。

关键词：潮控海湾沉积成因Sr/Ba 潮滩相沉积环境海平面变化全新世

Mineralogical, REE-geochemical and fluid inclusion studies on some uranium occurrences, gabal gattar, Northeastern Desert, Egypt

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Chinese Journal Of geochemistry 2011年第4期30卷 430-443页

作者： el-Feky M.g. Nuclear Materials Authority

Altered granite occurrences (gII and gV) at gabal (g.) gattar are the most important mineralized rocks hosting U-mineralization in Egypt. This mineralized granite is affected by multi-stage hydrothermal alteration proc-esses along brittle structures. This alteration comprises pre-ore alkali-metasomatism and ore-stage hydrothermal hematitization, silicification, kaolinitization, fluoritization, carbonatization and episyenitization. Autoradiographic examination indicates that primary uranium mineralization is present as massive or disseminated ores along tectonic fractures, interstitially in granular minerals, and as cements of breccias. Uraninite, pitchblende and coffinite are the main primary minerals, while uranophane and kasolite are the secondary ones. galena, chalcopyrite, pyrrohtite and pyrite are the most abundant sulphides in association with uranium mineralizations. Hydrothermal alterations at the gII occurrence exhibit an increase in Ni, Cu, Zn, Pb, Mo, Nb, Rb beside HREEs and a decrease in Ba, Co, Sr, and V, while alterations at the gV occurrence show enrichment in Ni, Cu, Pb, Mo, Nb, Y, HREEs and depletion in Zn, Ba, Co, Rb, Sr, and V. Hydrothermal alteration during the late magmatic stage is also identified through the development of unusual REE patterns and fractionation of ratios like Zr/Hf and Y/Ho out of the CHARAC (Charge Radius Con-trolled) range. Non-chondritic Y/Ho ratio at gV is of larger value than chondritic one which may result from wa-ter-rock interaction or print from the encompassing sedimentary rocks. Fluid inclusion studies on quartz and fluorite revealed that temperatures of the mineralizing fluids range between 126 and 240℃ at pressure ≤0.5×108 Pa and give salinity values ranging between 1 wt% and 7.8 wt% NaCl equivalent.

关键词：稀土元素地球化学流体包裹体铀矿化矿物学埃及全球信息基础设施东北部沙漠

generic phase portrait analysis of finite-time singularities and generalized Teleparallel gravity

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Chinese Physics C 2017年第12期41卷 133-154页

作者： W. el Hanafy g.g.L. Nashed Centre for Theoretical Physics The British University in Egypt P.O. Box 43 El Sherouk City Cairo 11837 Egypt Mathematics Department Faculty of Science Ain Shams University Cairo 11566 Egypt Egyptian Relativity group (ERg) Cairo University Giza 12613 Egypt

We analyze the four common types of finite-time singularity using a generic framework of the phase portrait geometric approach. This technique requires the Friedmann system to be written as a one-dimensional autonomous system. We employ a scale factor that has been used widely in the literature to realize the four finite- time singularity types, then we give a detailed discussion for each case showing possible novel models. Moreover, we show how different singularity types can play essential roles in different cosmological scenarios. Among several modified gravity theories, we show that the f（T） cosmology is compatible with the phase portrait analysis, since the field equations include Hubble derivatives only up to first order. Therefore, we reconstruct the f（T） theory which generates these phase portraits. We also perform a complementary analysis using the effective equation of state. Furthermore, we investigate the role of the torsion fluid in realizing the cosmic singularities.

关键词： inflation bounce big brake ACDM teleparallel gravity

electronic and thermoelectric properties of YbMg_(2)X_(2)(X=P,As,Sb,Bi)zintl compounds by first-principles method

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Journal of Rare Earths 2024年第1期42卷 147-154,I0006页

作者： Sajid Khan Dil Faraz Khan R.Neffati Tariq Usman Muhammad Waqar Ahsraf Shamim Khan Saeed Ullah Jan g.Murtaza Department of Physics University of Science&Technology BannuBannu28100Pakistan Department of Physics Faculty of ScienceKing Khalid UniversityP.O.Box 9004AbhaSaudi Arabia Laboratoire de Physique de La Matiere Condensee Departement de PhysiqueFaculte des Sciences de TunisUniversite Tunis El ManarCampus Universitaire1060TunisTunisia Department of Physics Shaoxing UniversityShaoxing312000China Department of Mathematics&Natural Sciences Prince Mohammad Bin Fahd UniversityAlkhobar31952Saudi Arabia Materials Modeling Lab Department of PhysicsIslamia College Peshawar25120KhyberPakhtunkhwaPakistan

In this work the structural,electronic and thermoelectric properties of YbMg_(2)X_(2)(X=P,As,Sb,Bi)zintl compounds were investigated comprehensively using first principles *** electronic properties were studied using PBE ggA,TB-mBJ and hybrid(YS-PBE0)*** the structural parameters of optimized structures are in harmonious agreement to the available *** band structure study illustrates that the titled materials manifest metallic and semi metallic nature using PBE and TB-mBJ potentials while they show wide band gap semiconducting behavior by following hybrid(YS-PBE0)*** density of states(TDOS)and partial density of states(PDOS)were also calculated to glimpse the contribution of orbitals of atoms in the formation of *** properties were studied by using BoltzTraP2 code employed to *** get enormous values of Seebeck coefficient(S),power factor(PF)and thermoelectric figure of merit(ZT)for all the samples YbMg_(2)X_(2)(X=P,As,Sb,Bi),Moreover,the overwhelming transport properties for the titled compounds indicate the optimum level of carriers’concentration which pinpoints these materials to be better thermoelectrics in the 1-2-2 zintl family.

关键词： Zintl compounds Hybrid functional Band structure Thermoelectrics Rare earths

Analysis and Assessment of Wind Energy Potential of Socotra Archipelago in Yemen

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Computers, Materials & Continua 2022年第1期70卷 1177-1193页

作者： murad A.Almekhlafi Fahd N.Al-Wesabi Imran Khan Nadhem Nemri Khalid Mahmood Hany Mahgoub Noha Negm Amin M.el-Kustaban Ammar Zahary Department of electrical Engineering–Communication Engineering Sana’a UniversityYemen Department of Computer Science King Khalid UniversityMuhayel AseerKingdom of Saudi Arabia Faculty of Computer and IT Sana’a UniversitySana’aYemen Department of electrical Engineering University of Engineering and TechnologyPeshawarP.O.B 814Pakistan Department of Information Systems King Khalid UniversityMayahel AseerKSA Computer Science Department King Khaled UniversityKSA&Faculty of Computers and InformationComputer Science DepartmentMenoufia UniversityEgypt Computer Science Department King Khaled UniversityKSA&Faculty of ScienceDepartment of Mathematics and Computer ScienceMenoufia UniversityEgypt electronics Department Faculty of EngineeringUSTSana’aYemen Faculty of Computer and IT Sana’a UniversityYemen

The increasing use of fossil fuels has a significant impact on the environment and ecosystem,which increases the rate of *** the high potential of renewable energy sources inYemen and the absence of similar studies in the region,this study aims to examine the potential of wind energy in Socotra *** was done by analyzing and evaluating wind properties,determining available energy density,calculating wind energy extracted at different altitudes,and then computing the capacity factor for a number of wind turbines and determining the *** average wind speed in Socotra Island was obtained from the Civil Aviation and Meteorology Authority data,only for the five-year data currently *** results showed high wind speeds from June to September(9.85-14.88 m/s)while the wind speed decreased for the rest of the *** average wind speed in the five years was 7.95 m/*** average annual wind speed,wind energy density,and annual energy density were calculated at different altitudes(10,30,and 50 m).According to the International Wind Energy Rating criteria,the region of Socotra Island falls under Category 7 and is classified as‘Superb’for most of the *** study provides useful information for developing wind energy and an efficient wind approach.

关键词： Energy potential wind characteristics Weibull distribution wind power density Socotra island

Mineralogy,geochemistry,radioactivity and environmental impacts of gabal Marwa granites,southeastern Sinai,Egypt

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Chinese Journal Of geochemistry 2011年第2期30卷 175-186页

作者： el Feky M.g. el Mowafy A.A. Abdel Warith A. Nuclear Materials Authority MaadiCairoEgypt

The gabal Marwa area is located in the southeastern part of Sinai,*** comprises gneisses and migmatites,granodiorites and ***,petrographic,mineralogic and chemical investigations indicated that the gabal Marwa granites are classified as granodiorites and *** monzogranites constitute the most predominant rock unit exposed in the study *** have been subjected to hydrothermal alterations,especially along the shear ***,desilicification,nametasomatism and development of spotty or dendritic manganese oxides are the most pronounced alteration *** alterations resulted in the increase of TiO2,Al2O3,FeOt,MnO,CaO,MgO,Na2O,K2O and Cr,Zr,Rb,Y and Sr and the decrease of SiO2,P2O5,Ni,Zn,Ba and *** studies indicated that the altered granites belong to high thorium,high uranium *** U,Th,U and Th,Th/U,Th and U-K variation diagrams suggested that magmatic processes controlled the distribution of these elements but the effect of hydrothermal alteration processes were clearly *** Scanning electron Microscope and X-ray Diffraction analyses indicated that the most important radioactive minerals include uranothorite,thorite,zircon,monazite and *** and Mn minerals were also *** the U,Th,Ra and K activity concentrations obtained for all the studied granitic samples,radium equivalent activity(Raeq),external hazard index(Hex),and internal hazard index(Hin),were calculated to assess the radiation hazard to human beings living in dwellings made of the studied *** monzogranites have radioactivity above the proposed acceptable level and,therefore,caution must be taken when these granites are used as building materials.

关键词： granodiorite monzogranites 放射性 gabal Marwa 西奈埃及

Mineralogy,M-type tetrad effect and radioactivity of altered granites at the *** garadi shear zone,central Eastern Desert,Egypt

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Chinese Journal Of geochemistry 2011年第2期30卷 153-164页

作者： el Nahas H.A. el Feky M.g. Mira H. Nuclear Materials Authority P.O. Box 530 Cairo Egypt

The g. Abu garadi area is covered mainly by metasediments, alkali feldspar granites and stream sediments. The alkali feldspar granite is traversed by a major strike-slip fault trending in an N-S direction as well as two subordinate sets of faults trending NW to WNW for the first one and NE for the second one. These faults represent the shear zones affected by magmatic (syngenetic) as well as hydrothermal (epigenetic) activities causing alteration of the granitic rocks. The most common alteration features are albitization, greisenization and koalinitization. The mass balance calculations of the studied altered samples show enrichments in Zr, Y, Ni, U, Th and ga and depletions in Zn, Sr, Nb, Ba, Pb, Cu and V. Only the greisenized samples exhibit a significant enrichment in Nb, ∑REE budget and pronounced lanthanide tetrad effect (M-type), especially TE1,4, while weakly expressed tetrad effects are for the other albitized and koalinitized samples. Mineralogically, the common accessory minerals in the altered samples include samarskite-(Y), betafite, uranothorite, zircon, fluorite and cassiterite. The greisenized granites contain high eU and eTh than the other altered types, where they are characterized by an assemblage of the radioactive minerals; samarskite-(Y), betafite, uranothorite in addition to zircon. The inter-element relationships between U and Th and also their ratios illustrate that the radioelement distribution in these granites is mainly governed by magmatic processes, in addition to post-magmatic ones. The distribution of chemical elements and the fractionation of some isovalents within the shear zone are largely controlled by the newly formed mineral phases. With respect to uranium mobilization, uranium migrated from the host alkali feldspar granites of g. Abu garadi, while the shear zones acted as traps for the migrated uranium. Moreover, U migrated in the shear zone during greisenization and albitization, and migrated out during koalinitization.

关键词： M 类型四个效果改变的花岗石 g。Abu garadi 砍地区中央东方沙漠埃及

Higher-Order Corrections to Earth's Ionosphere Shocks

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Communications in Theoretical Physics 2017年第1期67卷 90-96页

作者： H.g.Abdelwahed E.K.el-Shewy Plasma Technology and Material Science Unit(PTMSU) Physics DepartmentCollege of Science and Humanitarian StudiesPrince Sattam bin Abdulaziz UniversityAlkharjKSA Theoretical Physics group Physics DepartmentFaculty of ScienceMansoura UniversityMansouraEgypt

Nonlinear shock wave structures in unmagnetized collisionless viscous plasmas composed fluid of positive(negative) ions and nonthermally electron distribution are examined. For ion shock formation, a reductive perturbation technique applied to derive Burgers equation for lowest-order potential. As the shock amplitude decreasing or enlarging,its steepness and velocity deviate from Burger equation. Burgers type equation with higher order dissipation must be obtained to avoid this deviation. Solution for the compined two equations has been derived using renormalization analysis. Effects of higher-order, positive- negative mass ratio Q, electron nonthermal parameter δ and kinematic viscosities coefficient of positive(negative) ions η1 and η2 on the electrostatic shocks in Earth's ionosphere are also argued.

关键词： nonthermal electrons ion shock waves Burgers equation Burger type equation renormalization method higher-order dissipation