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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

Changing dietary n-6:n-3 ratio using different oil sources affects performance,behavior,cytokines mRNA expression and meat fatty acid profile of broiler chickens

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Animal Nutrition 2018年第1期4卷 -页

作者： Doaa Ibrahim Rania el-Sayed Safaa I.Khater Enas N.Said Shefaa a.m.el-mandrawy Department of Nutrition and Clinical Nutrition Faculty of Veterinary MedicineZagazig University Department of Biochemistry Faculty of Veterinary MedicineZagazig University Department of Veterinary Public Health Faculty of Veterinary MedicineZagazig University Department of Clinical Pathology Faculty of Veterinary MedicineZagazig University

Typical formulated broiler diets are deficient in n-3 poly-unsaturated fatty acids(PUFA) due to widening n-6:n-3 PUFA ratio which could greatly affect performance,immune system of birds and,more importantly,meat *** study was conducted to evaluate the effect of modifying dietary n-6:n-3 PUFA ratio from plant and animal oil sources on performance,behavior,cytokine m RNA expression,antioxidative status and meat fatty acid profile of broiler ***(n=420) were fed 7 diets enriched with different dietary oil sources and ratios as follows: sunflower oil in control diet(C); fish oil(FO); 1:1 ratio of sunflower oil to FO(C1 FO1); 3:1 ratio of sunflower oil to fish oil(C3 FO1); linseed oil(LO); 1:1 ratio of sunflower oil to linseed oil(C1 LO1); 3:1 ratio of sunflower oil to linseed oil(C3 LO1),resulting in dietary n-6:n-3 ratios of approximately 40:1,1.5:1,4:1,8:1,1:1,2.5:1 and 5:1,*** best final body weight,feed conversion ratio as well as protein efficiency ratio of broilers were recorded in the C1 FO1 and C1 LO1 *** with the control group,the dressing percentage and breast and thigh yield were highest in the C1 FO1 and C1 LO1 *** the dietary n-6:n-3 ratio increased(P meat contents of eicosapentaenoic acid and docosahexaenoic acid increased(P m FO and LO clearly decreased(P m total cholesterol,triglycerides and very low-density lipoproteins and enhanced antioxidative *** feeding frequency was decreased(P mpared to plant oil,to broiler diets enhanced the relative m RNA expression of interferon gamma,interleukin-1 beta,interleukin-2 and

关键词： Broiler n-6:n-3 PUFA ratio Performance Antioxidant status meat Immunity

Combining ability of Egyptian cotton(Gossypium barbadense L.)reveals genetic potential for improved yield and fiber quality

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Journal of Cotton Research 2024年第2期7卷 109-122页

作者： Abdelghany Ahmed m. el-Banna Aly A.A. Lamlom Sobhi F el-Sorady Gawhara A. Salama Ehab A.A. Ren Honglei Shaibu Abdulwahab S. Yehia Waleed m.B. Crop Science Department Faculty of AgricultureDamanhour UniversityDamanhour 22516Egypt Plant Production Department Faculty of Agriculture Saba BashaAlexandria UniversityAlexandria 21531Egypt Agricultural Botany Department Faculty of Agriculture Saba BashaAlexandria UniversityAlexandria 21531Egypt Heilongjiang Academy of Agricultural Sciences Soybean Research InstituteHarbin 150086China Department of Agronomy Bayero University KanoKano 700001Nigeria Cotton Breeding Department Cotton Research InstituteAgriculture Research CenterGizaEgypt

Background As the most widely cultivated fiber crop,cotton production depends on hybridization to unlock the yield potential of current varieties.A deep understanding of genetic dissection is crucial for the cultivation of enhanced hybrid plants with desired traits,such as high yield and fine fiber *** this study,the general combining ability(GCA)and specific combining ability(SCA)of yield and fiber quality of nine cotton parents(six lines and three testers)and eighteen F1 crosses produced using a line×tester mating design were *** The results revealed significant effects of genotypes,parents,crosses,and interactions between parents and crosses for most of the studied ***,the effects of both additive and non-additive gene actions played a notably significant role in the inheritance of most of the yield and fiber quality *** F1 hybrids of(Giza 90×Aust)×Giza 86,Uzbekistan 1×Giza 97,and Giza 96×Giza 97 demonstrated superior performance due to their favorable integration of high yield attributes and premium fiber quality *** analysis revealed that lint yield has the highest positive direct effect on seed cotton yield,while lint percentage showed the highest negative direct effect on seed cotton *** component analysis identified specific parents and hybrids associated with higher cotton yield,fiber quality,and other agronomic *** This study provides insights into identifying potential single-and three-way cross hybrids with superior cotton yield and fiber quality characteristics,laying a foundation for future research on improving fiber quality in cotton.

关键词： Gossypium barbadense L. Combining ability Seed cotton yield Fiber quality Cluster analysis Path analysis

Estimation of radiation hazard indices from natural radioactivity of some rocks

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Nuclear Science and Techniques 2006年第2期17卷 118-122页

作者： A.ABBADY N.K.AHmED a.m.el-ARABI R.mICHel A.H.el-KAmel A.G.E.ABBADY Physics Department Faculty of Science Qena South Valley University Egypt Institute of the Radiation Protection and Radioecology Hannover University Germany Physics Department Faculty of Science Assiut University Egypt

Different samples of igneous and metamorphic rocks from Egypt and Germany have been considered to measure γ-ray activity concentrations due to naturally occurring, potentially hazardous radonuclides 226Ra, 232Th and 40K. The radiation hazard parameters including radiation equivalent activity, gamma-absorbed dose rate, and exter- nal and internal hazard indices have been estimated. The gamma-absorbed dose rates in air of rocks in Egypt range from 4.2 to 128.5 nGy·h-1 with a mean value of 55.3 nGy·h-1. For igneous and metamorphic rocks from Germany, the values of absorbed dose rates fluctuate from 5.1 to 148.6 nGy·h-1, with a mean value of 60.9 nGy·h-1. Generally, it is found that the radiation hazard indices in common igneous rocks are distinctly higher in acidic than in ultrabasic rocks. The results are discussed and compared with the corresponding published data.

关键词：自然放射性岩石变质岩环境放射学

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

Uncovering the dominant contribution of intermediate volatility compounds in secondary organic aerosol formation from biomass-burning emissions

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National Science Review 2024年第3期11卷 150-158页

作者： Kun Li Jun Zhang David m.Bell Tiantian Wang Houssni Lamkaddam Tianqu Cui Lu Qi mihnea Surdu Dongyu Wang Lin Du Imad el Haddad Jay G.Slowik Andre S.H.Prevot Environment Research Institute Shandong University Laboratory of Atmospheric Chemistry Paul Scherrer Institute

Organic vapors from biomass burning are a major source of secondary organic aerosols(SOAs). Previous smog chamber studies found that the SOA contributors in biomass-burning emissions are mainly volatile organic compounds(VOCs). While intermediate volatility organic compounds(IVOCs) are efficient SOA precursors and contribute a considerable fraction of biomass-burning emissions, their contribution to SOA formation has not been directly observed. Here, by deploying a newly-developed oxidation flow reactor to study SOA formation from wood burning, we find that IVOCs can contribute ～70% of the formed SOA, i.e.>2 times more than VOCs. This previously missing SOA fraction is interpreted to be due to the high wall losses of semi-volatile oxidation products of IVOCs in smog chambers. The finding in this study reveals that SOA production from biomass burning is much higher than previously thought, and highlights the urgent need for more research on the IVOCs from biomass burning and potentially other emission sources.

关键词： atmospheric chemistry biomass burning secondary organic aerosol intermediate volatility organic compounds

Ultralong hydroxyapatite-based forward osmosis membrane for freshwater generation

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Frontiers of Chemical Science and Engineering 2024年第9期18卷 37-49页

作者： mohamed Gamal Gomaa Hamdy maamoun Abdel-Ghafar Francesco Galiano Francesca Russo Alberto Figoli el-Sayed Ali Abdel-Aal Abdel-Hakim Taha Kandil Bahaa Ahmed Salah Central metallurgical Research and Development Institute(CmRDI) 11421 CairoEgypt Chemistry Department Faculty of ScienceHelwan University11795 CairoEgypt Institute on membrane Technology(CNR-ITm) 87036 RendeItaly

Increasing global water shortages are accelerating the pace of membrane manufacturing,which generates many environmentally harmful *** challenges need a radical rethink of developing innovative membranes that can address freshwater production without generating environmentally harmful *** work utilized the synthesized ultra-long hydroxyapatite(UHA)by the solvothermal method using the green solvent oleic acid in preparing UHA-based forward osmosis *** membranes were developed using different loading ratios of graphene oxide(GO)by vacuum-assisted filtration *** prepared GO/UHA membranes were identified using X-ray diffraction,scanning electron microscope,Fourier-transform infrared spectroscopy,and X-ray photoelectron *** contact angle and pore size distribution were determined for the obtained GO/UHA *** obtained hierarchical porous structure in the prepared membranes with interconnected channels results in a stable water flux with reverse salt *** best water flux rate of 42±2 L·m^(–2)·h^(–1)was achieved using the 50 mg GO/UHA membrane,which is 3.3 times higher than the pristine membrane,and a reverse salt flux of 67 g·m^(-2)·h^(–1).The obtained results showed a promising capability of a new generation of sustainable inorganic-based membranes that can be utilized in freshwater generation by energy-efficient techniques such as forward osmosis.

关键词： forward osmosis ultra-long hydroxyapatite graphene oxide inorganic-based membrane

Robust Giant Octahedral[6+8]Porous Organic Cages for Efficient Ethylene/Ethane Separation

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CCS Chemistry 2024年第9期6卷 2264-2274页

作者： Lijuan Feng Yan-Xi Tan el-Sayed mel-Sayed Fenglei Qiu Wenjing Wang Kongzhao Su Daqiang Yuan State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002 College of Chemistry Fuzhou UniversityFuzhou 350116 Chemical Refining Laboratory Refining Department Egyptian Petroleum Research InstituteNasr CityCairo 11727 University of the Chinese Academy of Sciences Beijing 100049 Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108

The exploration of ethane(C_(2)H_(6))-selective porous materials for the direct production of polymer-grade ethylene(C_(2)H_(4))from a C_(2)H_(6)/C_(2)H_(4) mixture in a single energy-saving adsorption step is of utmost importance but remains a significant ***,developing robust C_(2)H_(6)-selective adsorbents with high C_(2)H_(6) capacity and C_(2)H_(6)/C_(2)H_(4) selectivity is urgently needed for industrial *** this study,we have successfully designed and synthesized two novel calix[4]resorcinarene-based porous organic cages(POCs)named CPOC-501 and *** POCs were formed via a Schiff-base reaction involving face-directed[6+8]condensation between a bowlshaped tetratopic tetraformylcalix[4]resorcinarene and triangular tritopic amine *** using single crystal X-ray crystallography revealed that both cages possess large truncated octahedral cavities with a volume of approximately 6500Å3 and 12 accessible rhombic windows with a side length of approximately 10.5Å.Furthermore,the cages exhibited excellent chemical stability under neutral,acidic,and basic conditions and high Brunauer–Emmett–Teller specific surface areas of up to 2175 m^(2) g^(−1) after *** POCs demonstrated superior adsorption capabilities for C_(2)H_(6) over C_(2)H_(4).Notably,CPOC-502 exhibited a C_(2)H_(6) capacity and C_(2)H_(6)/C_(2)H_(4) selectivity of 83 cm^(3) g^(−1) and 2.83,respectively,surpassing most of the best-performing C_(2)H_(6)-selective porous organic materials reported to ***,breakthrough experiments confirmed that both cages efficiently produced polymer-grade C_(2)H_(4)(>99.9%)directly from the C_(2)H_(6)/C_(2)H_(4) mixture,highlighting their outstanding recyclability.

关键词： C_(2)H_(6)/C_(2)H_(4)separation porous organic cages calixresorcinarene gas adsorption and separation host-guest interactions

Endemics and endangered species in the biodiversity hotspot of the Shada mountains, Saudi Arabia

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Journal of Arid Land 2017年第1期9卷 109-121页

作者： Jacob THOmAS mohamed A el-sheikh Abdulrehman A ALATAR Department of Botany & microbiology College of Science King Saud University Riyadh 11451 Saudi Arabia Botany Department Faculty of Science Damanhour University Damanhour 22516 Egypt

Shada mountains in Saudi Arabia, separated by maleel Wadi into twin mountains（i.e., Shada Alalah and Shada Asfal）, are rich in biodiversity. We investigated the diversity of endemics and endangered species of the mountains based on the data collected from 38 stands falling in 8 elevational zones ranging from 500 to 2215 m a.s.l. Results indicated that 495 plant species falling in 314 genera and 76 families occurred in the Shada mountains, including 19 endemic species and 43 endangered species, and accounting for 22% of the total flora in Saudi Arabia. Canonical correlation analysis indicated that physiographic features, particularly altitude play an important role in the frequency and abundance of species. Endemics were not evenly distributed in the Shada mountains and mostly restricted in the elevation zone of 1000–1500 or ＆gt;1500 m a.s.l. When the altitude reached up to 2000 m a.s.l., the endemics decreased substantially due to the significantly low temperature. The endangered species existed three different distribution patterns：（i） most endangered species distributed in the altitudes of 1000–1800 m a.s.l.;（ii） endangered trees, lianas, and shrubs occupied the altitudes 1000–1300 m a.s.l.; and（iii） endangered subshrubs and herbs inhabited the altitudes 1500–2100 m a.s.l. The results demonstrated that the biodiversity of endangered species in the Shada mountains is high and undisturbed by invasive species, and protective measures should be taken against human disturbances to the small-scale hotspot.

关键词： elevational gradient invasion Shada Alalah Shada Asfal Wadi Jof