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Clustered Hyperbolic Categories

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Algebra Colloquium 2018年第1期25卷 81-106页

作者： ibrahim saleh mathematics Department University of Wisconsin 80 Regent Street Madison Wisconsin 53715 USA

We introduce a class of categories, called clustered hyperbolic categories, which are constructed from a categorized version of preseeds called categorical preseeds using categorical mutations that are a ＂functorial＂ edition of preseed mutations. Every Weyl preseed p gives rise to a categorical preseed P which generates a clustered hyperbolic category; this is formed by copies of categories each one of which is equivalent to the category of representations of the Weyl cluster algebra H（p）. A ＂categorical realization＂ of Weyl cluster algebra is provided in the sense of defining a map Fp from any clustered hyperbolic category induced from p to the Weyl cluster algebra H（p）, where the image of Fp generates H（p）.

关键词： cluster algebras Weyl cluster algebras representations theory categorification of generalized Weyl algebras

Geochemistry and spectrometric prospection of younger granites and granitic pegmatites bearing uranium mineralization at *** El Rakeb area, Central Eastern Desert, Egypt

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Acta Geochimica 2021年第4期40卷 575-601页

作者： Gehad m.saleh Bahaa m.Emad ibrahim B.Abdel Kader Nuclear materials Authority El MaadiP.O.Box 530CairoEgypt

The present study deals with the detailed field geology,mineralogy,geochemistry,and spectrometric prospection of rare metals and radioactive minerals associated with granitic pegmatites in the Gabal Um LassafAbu Dob-Um Atelia-Kadabora-Kab El Rakeb area(LDAKK),which are situated in the central Eastern Desert of *** study area is composed of granodiorites and *** latter is dissected by granitic pegmatites with a discriminatory distribution of economically important mineralization(rare-metals and U-Th minerals).The granitic pegmatites display a zoning structure composed of feldspar-rich zones enveloping pockets of mica(mostly muscovite) and all zoning internal quartz ***,the monzogranite and granitic pegmatites are composed of potash-feldspar,albite,and quartz with a small amount of biotite and *** mineralogical investigation of the highly radioactive zones in the granitic pegmatite shows enrichment in kasolite,uranothorite,thorite,xenotime,columbite,zircon,bismuth,and ***,the granitic pegmatites are enriched with high field strength elements(HFSE;Zr,Nb,Th,and U) and ion lithophilic elements(LILE;Rb,and Pb) and depleted in Ba,Sr,and *** are strongly peralkaline to metalumainous except for two samples,which are *** are formed by partial melting of metagreywackes at *** studied granitic pegmatites could belong to the NYF family(Niobium-Yttrium-Fluorine family) according to the geochemistry of the trace *** studied granitic pegmatites show deep negative Eu anomaly and display a strong m-type tetrad effect of rare earth *** field spectroscopy measurements showed the localization of the radiometric anomalous associated with the granitic pegmatites,which are intruded in the granitic host *** eU and eTh contents reached up to 316 and 1367 ppm,*** and thorium occurrences in the investigated granitic pegmatites are related to magmatic(syngenetic)ori

关键词： Geochemistry Gabal Um Lassaf-Abu Dob-Um Atelia-Kadabora-Kab El Rakeb area(LDAKK) Uranium REE Egypt

The possible source of uranium mineralization in felsic volcanic rocks,Eastern Desert,Egypt of the Arabian-Nubian Shield:Constraints from whole-rock geochemistry and spectrometric prospection

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Acta Geochimica 2021年第5期40卷 819-845页

作者： Gehad.m.saleh Bahaa.m.Emad ibrahim.B.Abdel Kader Rania.m.Sakr Nuclear materials Authority El MaadiP.O.Box 530CairoEgypt

The present work deals with the detailed geology,mineralogy,geochemistry,and spectrometric prospection of the felsic volcanic rocks at the Eastern Desert,Egypt of the Arabian-Nubian *** volcanic rocks are an essential source for rare earth elements(REEs)and uranium occurrences in this *** are compositionally uniform with tholeiitic to calc-alkaline affinities,peraluminous and belong to the series of rhyolite with high-K *** exhibit more enrichment in high field strength elements(HFSE,***,Ta,Nd,Th,and U)and large-ion lithophile elements(LILE,*** and Rb)compared to the country rocks of the studied area,with REE ranging from 188.20 to 442.70 ppm and strong depletion in Ti,Sr,P with deep negative Eu *** felsic volcanic rocks were mostly generated from the partial melting of quartz-amphibolite facies accreted during the *** oddities of Zr-U-Th for the felsic volcanic rocks determine the involvement of crustal *** volcanic rocks are found in A-type suites of magma and represent highly fractionated rocks derived from rhyolitic magma,with insignificant interaction with continental crust in the low-pressure environment and during fractional *** volcanic rocks have higher values of radioactivity in which eU range from 0.5 to 121 ppm and eTh from 1.0 to 415.10 *** high values of eU and eTh can be ascribed to the mineralization of uranium and the presence of accessory minerals of radiogenic nature such as uranophane,uranothorite,zircon,and *** is considered as the mineral with most enriched uranium contents in the studied felsic volcanic rocks in which(UO2=87.30 wt%).Also,they are enriched with REE-bearing accessory minerals comprising allanite,titanite,and *** geological investigations of the felsic volcanic rocks in the studied areas are inappropriate to clear the feasible economic potentialities of rare earth elements and U occurrences;itemized and invaluable

关键词： Felsic volcanic rocks Geochemistry REE Uranium mineralization Egypt Arabian-Nubian Shield

Ocellar lamprophyre dyke bearing mineralization,Wadi Nugrus,Eastern Desert,Egypt:Geology,mineralogy and geochemical implications

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Chinese Journal Of Geochemistry 2010年第4期29卷 383-392页

作者： ibrahim m.E. saleh G.m. Dawood N.A. Aly G.m. Nuclear materials Authority P.O.Box 530El-MaadiCairoEgypt

The ocellar lamprophyre dyke(ENE-WSW) is recorded at Wadi Nugrus,Eastern Desert,*** cuts porphyritic biotite granites and varies in thickness from 0.5 to 1.5 m and up to 3 km in *** lamprophyre dyke has been altered,and it is characterized by porphyritic and panidiomorphic textures with plagioclase,olivine,and augite constituting the porphyritic phase in a fine groundmass of the same ***,titanite,apatite,fluorite,graphite,calcite,allanite,autunite and Fe-Ti oxides are accessory ***,chlorite and epidote are secondary *** and hematitization are *** to sub-rounded porphyritic and zoned ocelli with radiate or brush-like shapes are generally common and represent physical traps for *** ocellar features are interpreted to represent the late stage of magmatic segregation or magmatic crystallization involving two immiscible magmatic *** studies of altered lamprophyre samples,based on X-ray diffraction(XRD) and environmental scanning electron microscopy(ESEm),indicate the presence of secondary uranium minerals(autunite and uranophane),associated with gold,silver,nickel,atacamite,molybdenum,pyrite and *** presence of kaolinite indicates a high temperature *** mixing of volatile fluids with meteoric water and fluid-wall rock interaction result in changes of pH and oxygen activity and deposition of base metals in reducing environs(graphite and pyrite).Precipitation of hematite probably decreased the pH of the solution and rose acidic *** sudden change in pH and temperature of the fluids would lead to destabilization of base metal complexes favoring their *** magma source of the Nugrus lamprophyre is determined to be between calc-alkaline and alkaline and it has HKCAB and shoshonitic nature and may be derived from decomposition melting of such a metasomatised lithospheric *** is a major fractional phase to account for a rapid

关键词：煌斑岩脉矿物学地球化学沙漠埃及地质学黑云母花岗岩矿化

Synthesis of amyl ester grafted on carbon-nanopolymer composite as an inhibitor for cleaner shale drilling

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Petroleum 2022年第4期8卷 529-537页

作者： Tawfik A.saleh mukaila A.ibrahim Department of Chemistry King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Chemistry and Biochemistry University of Lethbridge4401University DriveLethbridgeAlbertaT1K 3M4Canada

Wellbore instability in oil and gas industry well drillings is a significant challenge that is linked to shale swelling when shale interacts with free water molecules in the water-based drilling *** design of environmentally benign,biodegradable,and effective shale hydration inhibitors is a prominent objective of contemporary exploration in well-drilling fluids as a replacement for the common KCl which is detrimental to aquatic *** work reports the synthesis and potential of novel green acrylic polymer-amyl ester activated carbon(-C)nanocomposite to hinder shale hydration in formations during *** less hydrophobic acrylic acid-acrylamide-activated carbon-amyl ester(AA-AAm-C-Amyl)and more hydrophobic acrylic acid-acrylamide-octadecene-activated carbon-amyl ester(AA-AAm-OD-CAmyl)composites were synthesized,characterized,and tested with standard methods as a cleaner fluid additive for shale swelling inhibition,and their results compared with that of *** polymer matrixes displayed remarkable thermal *** also indicate that AA-AAm-C-Amyl and AA-AAm-OD-CAmyl composites could stabilize wellbore effectively with 95.2%and 93.7%anti-swelling ratio,and shale recovery capacity of 97%and 95.2%*** surface evaluation of the composite fluidtreated bentonite revealed that the mechanism of inhibition could be based on the collaborative action of nanopore plugging of carbon core and strong adsorption of the polymer component of the materials on clay surfaces via encapsulation and hydrogen bonding to form an impressive filter cake which could actively prevent water invasion into ***,AA-AAm-C-Amyl and AA-AAm-OD-C-Amyl composites could be a sustainable substitute for the conventional KCl as a shale inhibitor for welldrilling.

关键词： Clean shale drilling Sustainable materials Advanced technology Amyl ester activated carbon Polymer composite

An efficient nano-adsorbent via surfactants/dual surfactants assisted ultrasonic co-precipitation method for sono-removal of monoazo and diazo anionic dyes

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Chinese Journal of Chemical Engineering 2021年第12期34卷 225-236页

作者： marwa m.ibrahim Department of Chemistry Faculty of EducationAin Shams UniversityRoxy 11711CairoEgypt

To preserve the environment for civilization,we should remove the pollutants like toxic dyes by friendly and cost efficacious *** this study,the effect of surfactants or mixed surfactants on physicochemical,optical and adsorption properties of ternary mixed oxide CeO_(2)-ZrO_(2)-Al_(2) O_3(CZA) are *** ternary mixed oxide CZA was prepared by surfactants or mixed surfactants assisted ultrasonic coprecipitation *** physicochemical and optical properties are estimated by different techniques like XRD,TEm,EDX,FTIR,S_(BET) and UV-Vis/*** CZA_T and CZA_C have hybrid shapes and high surface *** adsorption properties of ternary mixed oxides adsorbents were characterized by sono-removing anionic dyes such as Congo red(CR) and Remazol red RB-133(RR).The different factors like contact time,different dye concentrations and temperatures also *** kinetics and isotherms applications showed that,the adsorption process was followed pseudo second order kinetics and the Freundlich isotherm ***,the adsorption is spontaneous and endothermic process through the thermodynamic ***,the results showed that the ternary mixed oxide nano-adsorbent(CeO_(2)-ZrO_(2)-Al_(2) O_3) is promising and functional materials for anionic dye sweep from wastewater.

关键词： CeO_(2)-ZrO_(2)-Al_(2)O_3 Surfactants Ultrasonic co-precipitation method Optical properties Wastewater Adsorption

The chromite deposits associated with ophiolite complexes, Southeastern Desert, Egypt: Petrological and geochemical characteristics and mineralization

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Chinese Journal Of Geochemistry 2006年第4期25卷 307-317页

作者： Gehad m. saleh Nuclear materials Authority P.O.Box: 530 El Maadi Cairo Egypt

The podiform chromitites occur in a well-preserved mantle sequence consisting of lherzolite-harzburgite with abundant lenses of olivine dunite. The podiform chromitite deposits are common as small and irregularly shaped masses in the Southeastern Desert (SED) of Egypt. The podiform chromitites exhibit a wide range of compositions from high Cr to high Al varieties. The Cr of chrome spinel ranges from 0.67 to 0.88 in olivine-dunite, quite similar to that of the high-Cr chromitite, whereas it is around 0.62 in lherzolite-harzburgite. Primary hydrous mineral inclusions, amphibole and phlogopite, in chrome spinel have been reported for the first time from the Pan-African Proterozoic podiform chromitites. On the other hand, petrographic and geochemical evidence suggests that podiform chromitites in the SED of Egypt were formed as a result of crystallization of mafic melts, probably of boninitic composition, the boninitic parental magmas were probably produced by a second stage of melting above a subduction zone. Three types of chromite ores can be distinguished within the SED of Egypt: (a) sulphide-poor podiform ores; (b) brecciated ores; and (c) sulphide-rich ores. Two textural types of inclusions in chromite are distinguished: (1) primary silicate inclusions generally have high mg-number (>96), Cr and Ni, and are dominated by pargasitic amphibole, forsterite, diopside, enstatite and Na-phlogopite. A diversity of primary and secondary platinum group minerals (PGm) is described from the chromitites, including alloys, sulphides, sulpharsenides and arsenides of Ru, Os, Ir, Rh, Ni, Cu, Fe and Co; (2) in addition to primary PGm and hydrous silicates, the fluids are of low to moderate salinity, sodium-dominated aqueous solutions with complex gas contents. Variable amounts of water, hydrogen, hydrocarbons, carbon dioxides and nitrogen have been determined in inclusion-rich samples. The chondrite-normalized PGE patterns of lherzolite-harzburgite and olivine-dunite have negative

关键词：铬铁矿沉淀蛇绿岩复合物东南沙漠埃及岩石学

Geologic relationships and mineralization of peralkaline/alkaline granite-syenite of the Zargat Na’am ring complex, Southeastern Desert, Egypt

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Chinese Journal Of Geochemistry 2006年第2期25卷 97-111页

作者： Gehad m. saleh Nuclear materials Authority P.O. Box: 530 EL Maadi Cairo Egypt

The Zargat Na’am ring complex crops out 90 km NW of Shalatin City in the Southeastern Desert of Egypt. The ring complex forms a prominent ridge standing high above the surrounding mafic-ultramafic hills. It is cut by two sets of joints and faults which strike predominantly NNW-SSE and E-W, and is injected by dikes, porphyritic alkaline syenites, and felsite porphyries. It consists of alkali syenites, alkali quartz syenites, and peralkaline arfvedsonite-bearing granitic and pegmatitic dikes and sills. The complex is characterized locally by extreme enrichments in REEs, wolframite and rare, high field strength metals (HFSm), such as Zr and Nb. The highest concentrations ({1.5} wt% Zr, {0.25} wt% Nb, {0.6} wt% ∑REEs) occur in aegirine-albite aplites that formed around arfvedsonite pegmatites. Quartz-hosted melt inclusions in arfvedsonite granite and pegmatite provide unequivocal evidence that the peralkaline compositions and rare metal enrichments are primary magmatic features. Glass inclusions in quartz crystals also have high concentrations of incompatible trace elements including Nb (750×10+{-6}), Zr (2500×10+{-6}) and REEs (1450×10+{-6}). The REEs, Nb and Zr compositions of the aegirine-albite aplites plot along the same linear enrichment trends as the melt inclusions, and Y/Ho ratios mostly display unfractionated, near-chondritic values. The chemical and textural features of the aegirine-albite aplites are apparently resultant from rapid crystallization after volatile loss from a residual peralkaline granitic melt similar in composition to the melt inclusions.

关键词：花岗岩埃及矿化作用地质条件

Geology and rare-earth element geochemistry of highly evolved, molybdenite-bearing granitic plutons, Southeastern Desert, Egypt

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Chinese Journal Of Geochemistry 2007年第4期26卷 333-344页

作者： Gehad m. saleh Nuclear materials Authority P.O.Box: 530 El Maadi Egypt

The field relations, mineralogy, and major and trace elements (including REE analyses of whole-rock samples and minerals) of granites and their associated molybdenite + uranium mineralized aplites in Southeastern Desert, Egypt, have been studied. The granites are leucocratic and mostly peraluminous in nature with muscovite increasing at the expense of biotite. The chemical and mineralogical characteristics of the granitic rocks indicate that their melts originated from the LILE-enriched mantle wedge by partial melting and are contaminated by crustal melts, followed by thermogravitational processes. Leucogranites with higher Na2O/K2O ratios from Um Dargag and Um maiat crystallized under H2O-saturated equilibrium conditions in which the exsolved vapor continuously migrated away. The REE patterns of the granites studied are characterized by LREE enrichments and negative Eu anomalies. In comparison, the potassic aplites and the more sodic leucogranites are depleted in LREE, enriched in HREE and show more remarkable negative Eu anomalies. Allanite and monazite are the most important REE carriers in the granites. These minerals are strongly enriched in LREE, whereas fluorite and xenotime, which are more abundant in the aplites, are enriched in HREE. The average Lu/Ce ratio represents the fractionation trend with respect to HREE. It is 0.71 for radioactive fluorite, and it increases to 1.22 for non-radioactive fluorite. The high REE contents of molybdenite represent re-deposition of the mobilized mo and REE. Due to the strong control of accessory minerals, the REEs are of limited use in petrogenetic modelling of highly evolved granitic systems.

关键词：辉钼矿稀土资源褐帘石独居石西南地区沙漠地带埃及