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Petrology, geochemistry, radioactivity, and M–W type rare earth element tetrads of El Sela altered granites, south eastern desert,Egypt

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Acta Geochimica 2019年第1期38卷 95-119页

作者： A.M.El Mezayen M.A.Heikal M.G.El-Feky H.A.Shahin I.K.Abu Zeid S.R.Lasheen Geology Department Faculty of Science Al Azhar University nuclear material authority

The southern part of the Eastern Desert of Egypt—about 30 km southwest of Abu-Ramad city—is mainly covered by ophiolitic rocks(Sul Hamed), island arc assemblage, younger granites(muscovite granites of Qash Amer and two mica granites of El Sela), and various acidic and basic dikes. Field, petrological, and geochemical studies indicate that the El Sela shear zone has been subject to hydrothermal and supergene alteration such as kaolinization, albitization, sericitization, and hematitization. It is invaded by quartz ENE–WSW veins associated with hydrothermal alteration accompanied by radioactive mineralization. The investigated younger granitic rocks had very low contents of compatible elements, such as Cr, Ni,and Co; and high contents of incompatible elements, such as Zr, and large ion lithophiles, such as Sr, especially in the El Sela shear zone. Major oxide and trace element analyses revealed calc-alkaline affinity and peraluminous *** highly differentiated granitic rocks' lower Zr/Hf and higher Y/Ho than the normal ratio are consistent with hydrothermal alteration. Most samples had rare earth element(REE)-patterns with an M-type tetrad effect in the first and fourth segments and a W-type tetrad in the third segment. The average ∑REE in the studied granites was lower than the world granite average; the ratio of light to heavy REEs greater. The main radioactive, uranium-bearing, and uraniferous Fe and Mn minerals are uranothorite,autunite, uranophane and autunite as compounds, kasolite,columbite, xenotime, uranophane-bearing zircon and jarosite, silver-bearing pyrite, hematite, and autunite-bearing pyrolusite.

关键词： Geochemistry REE-tetrad effect Radioactive minerals Radiometric measurements Qash Amer El Sela

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Geochemistry, mineralogy, and radioactivity of the Abu Furad Area, Central Eastern Desert, Egypt

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Acta Geochimica 2019年第2期38卷 307-326页

作者： A.M.El Mezayen E.K.Abu Zeid W.S.Hosny M.G.El-Feky S.M.Omar S.A.Taalab Geology Department Faculty of Science Al Azhar University nuclear material authority Cairo Egypt

Abu Furad is in the Central Eastern Desert,Egypt. It comprises metasediments, metavolcanics,metagabbros, syn-to late-orogenic granites, and post-orogenic granites, in addition to numerous dykes and veins of different shapes and composition invading all the older rocks cropping out in the study area. Field, petrographic,mineralogical, and chemical investigations led to the classification of Abu Furad granites as quartz diorite, tonalite,granodiorite, and *** oxide and trace element data revealed that the syn-to late-orogenic granites and post-orogenic granites are peraluminous. Syn-to lateorogenic granites originated from calc-alkaline volcanic arc–related magma; while the post-orogenic granites(syenogranite) are highly fractionated, calc-alkaline granite from a within plate regime. Radiometrically, the studied quartz diorite, tonalite, and granodiorite had lower uranium and thorium contents and higher eU/eTh ratios than the syenogranites. This may indicate that the syn-to late-orogenic rocks originated from sources depleted in these elements. The average e Th/eU ratio of syenogranites was higher than that of average continental crust, suggesting that the syenogranites are relatively depleted in U. The studied altered syenogranites were strongly enriched in U and Th compared to the Earth's crust. On the other hand, the average of e U in pegmatites is lower than the global average for uraniferous pegmatites. The most recorded accessory minerals in the altered syenogranites were thorite, fergusonite, samarskite, columbite, zircon, monazite, xenotime,apatite, fluorite, sphene, atacamite, and malachite, in addition to chromium and nickel inclusions.

关键词： Hydrothermal alterations Major oxide and trace elements Radiometry Mineralogy Geochemistry Altered syenogranites Egypt

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Geology and geochemistry of the granitic rocks and associated dykes,East Gabal Nuqra,South Eastern Desert,Egypt

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Chinese Journal Of Geochemistry 2012年第4期31卷 376-389页

作者： Ibrahim H.Ibrahim Mostafa E.Darwish nuclear material authority 530 P.O.El MaadiCairoEgypt

A crescent-shape granitic stock and associated dykes is located to the East Gabal Nuqra at the extreme western part of Wadi Natash,South Eastern Desert,*** examined granites are classified as alkali-feldspar granites and mainly consist of quartz,potash feldspars,plagioclases,and ***,zircon,apatite and allanite are accessories representing the source of Y,U,Th and REEs in these *** granites are characterized by high K2O,Na2O and Zn contents and Rb/Sr ***,they are highly enriched in high field strength elements(HFSE),especially Zr(1529×10-6),Nb(100×10-6),Hf(91×10-6) and Y(624×10-6) and light rare-earth elements(LREE,141×10-6) concentrations and strongly depleted in Ca,Mg,Sr and Eu *** features suggest that they are similar to A-type granites(type-2).The rhyolite dykes and granites have similar geochemical characteristics whereas the chondrite-normalized REE patterns show a LREE enriched feature with strong negative Eu-anomaly,whereas the REE pattern of trachydacites show slightly fractionated pattern with no *** is suggested that the trachydacites were generated by small degree of partial-melting deep-seated basic *** liquid,when subjected to fractional crystallization involving separation of plagioclases as residue,generated the alkali-feldspar *** further fractional crystallization gave rise to the alkali *** igneous rock suite originated from metaluminous to alkaline trachytic magma,and was developed in a within-plate tectonic *** extension caused by NW-SE right-lateral shear in area led to the emplacement of the alkali-feldspar *** later extrusion of the alkali rhyolite and trachydacite dykes was due to cauldron subsidence.

关键词：碱长花岗岩地球化学特征堤坝沙漠埃及轻稀土元素碱性流纹岩元素富集特征

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Leakage of nuclear material powder from pressure container through a small orifice

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Particuology 2014年第3期12卷 117-123页

作者： Longbo Liu Yanmin Wu Yongyang Su Hanbing Tang Zhihong Zhang Ping Huang Lili Zhang Lixing Zhang Northwest Institute of nuclear Technology

Because of the radioactivity and toxic nature of nuclear materials, their containment within oxide matrices, encased in sealed containers, has been proposed as a suitable means for storage and transportation. However, container failures because of cracks or small orifices present a major leakage risk for nuclear materials, consequently posing a significant hazard to the environment and human beings. In this study, terbium oxide powder was used as a nuclear material representative to examine the leakage of nuclear material powder through orifices located at the base of a pressure container. The dependence of the orifice diameter, the powder layer thickness, and the internal pressure of the container on the leakage mechanism and amount was examined. A simplified model correlating the dependence of the above-mentioned parameters to determine the utmost leakage amount was also developed based on the present results. The leakage of the nuclear material powder was assessed by measuring its concentration using an optical particle counter. The diameter of the orifice determined the powder leakage mechanism, which in turn influenced the amount of leakage produced. Comparison studies showed that unlike the changes in the differential pressure, the volume of the container has little effect on the leakage amount. Under sufficiently high internal pressures, the oxide powder can be released as a fine aerosol. The work is not only crucial from the nuclear safety aspect, but is also beneficial for the safe application of powder and nanoparticles.

关键词： nuclear materials Powder Leakage Risk assessment

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Autunite-Group Minerals and Their Paragenesis from the Sheared Granite of Gabal El Sela, South Eastern Desert, Egypt

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Open Journal of Geology 2020年第6期10卷 703-725页

作者： Ehab K. Abu Zeid nuclear material authority Cairo Egypt

G. El Sela is located in the Southern Eastern Desert of Egypt cropping as two parts, occupied by monzogranites that were categorized as biotite granite, muscovite granite and two mica granites. The northern part is more significant according its high concentrations of uranium that controlled by complicated structure regime;faulting, infrastructures and shearing are the most common structural criteria of this part. The Egyptian nuclear materials authority (NMA) mined this part to produce the uranium ore. The previous mineralogical studies indicated that this granite was dominated by primary uranium minerals (pitchblende and coffinite) and secondary minerals belong to the autunite group (autunite, metautunite, phurcalite) in addition to uranophane. In the present work, petrographic and mineralogical studies are applied for the granites using the polarized and stereo microscopes and followed by electron microscope and XRD. The result of the microscopic examinations revealed the tectonic regime controlling the radioactivity and recognized the sodic autunite (meta-natroautunite) beside the pre-mentioned autunite group minerals completing the paragenetic sequrnce of these minerals. In this study, it is concluded that the sheared biotite granite is monzogranite originated during the episode of the continental plate collision (syncollision). The study finished to presence of two main types of the alteration corresponding to the two high levels of radioactivity (moderate and anomalous). The first is the thermal alteration (saussiritization, sericitization, kaolinization, silicification and hematization) and the second is the chemical transformation (oxidation, dehydration, ion substitutions and confusion) responsible for formation of the secondary uranium minerals. The temperature needed for the thermal alteration is sourced by the hydrothermal solutions, while the temperature needed for the uranium minerals transformation may be generated during the episode of the continent

关键词： Autunite-Group Paragenesis Thermal Alteration Chemical Alteration Confusion

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Effects of carbon content on the microstructure and tensile properties of a low-density steel

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International Journal of Minerals,Metallurgy and materials 2025年第2期32卷 391-401页

作者： Yongxuan Shang Mingyu Fan Shuyong Jiang Zhongwu Zhang Key Laboratory of Superlight materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China State Key Laboratory of Metal material for Marine Equipment and Application Iron&Steel Research Institute of Ansteel Group CorporationAnshan 114009China

Carbon can change the phase components of low-density steels and influence the mechanical *** this study,a new method to control the carbon content and avoid the formation ofδ-ferrite by decarburization treatment was *** microstructural changes and mechanical characteristics with carbon content induced by decarburization were systematically ***-Jaoul(C-J)analysis was employed to examine the work hardening characteristics during the tensile *** decarburization by heat treatments,the carbon content within the austenite phase decreased,while Mn and Al were almost unchanged;this made the steel with full austenite transform into the austenite and ferrite dual ***,(Ti,V)C carbides existed in both matrix phase and the mole fraction almost the *** addition,the formation of other carbides *** loss induced a decrease in strength due to the weakening of the carbon solid *** the steel with the single austinite,the deformation mode of austenite was the dislocation planar glide,resulting in the formation of *** the dual-phase steel,the deformation occurred by the dislocation planar glide of austenite first,with the increase in strain,the cross slip of ferrite took place,forming dislocation cells in *** the late stage of deformation,the work hardening of austinite increased rapidly,while that of ferrite increased slightly.

关键词： low-density steels carbon content decarburization strengthening mechanisms work hardening behavior

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Life cycle assessment of oxygen-18 production using cryogenic oxygen distillation

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Chinese Journal of Chemical Engineering 2018年第9期26卷 1960-1966页

作者： Meysam Akbarian Shourkaei Abbas Rashidi Javad Karimi-Sabet Faculty of Engineering University of Mazandaran material and nuclear Fuel Research School (MNFRS) Nuclear Science and Technology Research Institute

In this study, life cycle assessment of oxygen-18 by using cryogenic distillation of oxygen is performed using SimaPro 8.3 software. Life cycle assessment is performed to understand the environmental profile and hotspots of this process in order to be used in design and development. Simulation of oxygen-18 process is executed by Hysys software, and the required inputs and outputs for inventory of life cycle were acquired. By doing life cycle assessment and considering achieved results after characterization and normalization of inventory data it has been investigated that in the majority of environmental impacts electricity consumption has a huge contribution relative to other parts of the system like liquefied oxygen production from air separation unit,required facilities for air separation and oxygen-18 units, and needed transportation. Also, among 17 impact categories investigated in ReCiPe impact assessment method, fossil depletion, climate change(human health),particulate matter formation, climate change(ecosystem), human toxicity, and metal depletion have the most contribution in entire environmental loads respectively. Furthermore, sensitivity analysis showed that changing life cycle impact assessment method from ReCiPe to IMPACT 2002+ has no significant effect on acquired results and results are confident. In addition, assumption of market for depleted oxygen from heavy isotopes which is withdrawn from top of distillation columns showed some positive effects compared to first case and environmental impacts resulted from liquefied oxygen production(feed) reduced but because of huge contribution of electricity consumption compared to other sections, this positive effect has no remarkable influence on entire environmental loads of product system.

关键词： Life cycle assessment Oxygen- 18 production Cryogenic distillation Isotope separation

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Anisotropic Migration of Defects under Strain Effect in BCC Iron

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Chinese Physics Letters 2017年第7期34卷 164-167页

作者：高宁高飞王志光 Laboratory of Advanced nuclear material Institute of Modern PhysicsLanzhou Department of nuclear Engineering and Radiological Sciences University of Michigan

The basic properties of defects （self-interstitial and vacancy） in/3CC iron under uniaxial tensile strain are investi- gated with atomic simulation methods. The formation and migration energies of them show different dependences on the directions of uniaxial tensile strain in two different computation boxes. In box-1, the uniaxial tensile strain a/ong the （1005 direction influences the formation and migration energies of the （1105 dumbbell but slightly affects the migration energy of a single vacancy. In box-2, the uniaxial tensile strain along the 〈111〉 direction influences the formation and migration energies of both vacancy and interstitials. Especially, a 〈110〉 dumbbell has a lower migration energy when its migration direction is the same or close to the strain direction, while along these directions, a vacancy has a higher migration energy. Aft these results indicate that the uniaxial tensile strain can result in the anisotropic formation and migration energies of simple defects in materials.

关键词： der BCC 110

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Preparation of ZrO_2 nano-particles by the hydrolysis of ZrOCl_2 solution in the reverse micelles

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Journal of University of Science and Technology Beijing 2006年第4期13卷 355-358页

作者： Chensha Li Tongxiang Liang Tianyong Luo New material Division Institute of Nuclear Energy Technology Tsinghua University Beijing 102201 China

Zirconia nano-particles have been produced by the hydrolysis of ZrOCl2 solution in the reverse micelles of a liquid-liquid two-phase system, in which sodium bis（2-ethylhexyl） sulfosuccinite （AOT） and toluene were chosen as the surfactant and organic phase, respectively. The reverse micelles prevented the aggregation of primary particles and reduced the diameters of zirconia nanoparticles. Superfine zirconia powders soft-aggregated by the zirconia nano-particles were obtained. The diameters of zirconia nanoparticles were influenced by the quantity of the surfactant.

关键词： zirconia nanoparticles hydrolysis surfactant

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Microstructure and corrosion behavior of Zr–1.0Cr–0.4Fe–xMo alloys

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Rare Metals 2015年第2期34卷 118-124页

作者： Tian-Guo Wei Lu Zhang Zhi Miao Hong Liu Bai-Feng Luan Wen Wang Chong-Sheng Long Reactor Fuel and materials Key Laboratory Nuclear Power Institute of China nuclear and Radiation Safety Ministry of Environmental Protection Institute of material Science and Technology Chongqing University

Possibility of using Mo as an alloying element in Zr-based alloys was attractive in terms of microstructure refinement and mechanical properties strengthening. In this research, Zr–1.0Cr–0.4Fe–xMo（0, 0.2, 0.4, and 0.6） alloys with different Mo contents were prepared by vacuum arcmelting method, the microstructure and the corrosion resistance of these alloys were investigated. Addition of Mo has a refinement effect on the microstructure; with the increase of Mo content, the a-laths in the as-cast samples and the grain size in the annealed samples decrease. Zr–1.0Cr–0.4Fe–xMo alloys have large numbers of fine second-phase particles（SPPs） in the matrix, the area fraction of the SPPs is more than 10 %. With the increase of Mo content, the population density of the SPPs increases significantly, while the average diameter of the SPPs decreases. Mo addition also affects the texture; the intensity of basal pole texture aligning normal direction decreases with the increase of Mo content in the *** with Zr-4 and Zr–1Nb, Zr–1.0Cr–0.4Fe–xMo alloys have excellent corrosion resistance in 500 ℃/10.3 MPa steam. The corrosion rates of Mo-containing alloys are higher than that of Mo-free alloy, which is mainly attributed to the solute Mo atoms in the Zr *** of the SPPs features due to the increase of Mo content alleviates the degradation of corrosion resistance in some degree, but it is not the dominant factor.

关键词： Zr-based alloys Mo addition Microstructures Second-phase particles Corrosion behavior

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