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Application of Remote Sensing and GIS in Mineral Alteration Mapping and Lineament Extraction Case of Oudiane elkharoub (Requibat Shield, Northern of Mauritania)

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Open Journal of Geology 2024年第9期14卷 823-854页

作者： ould Mahmoud Hdeid Yousra Morsli Mohamed Raji Zouhir Baroudi Malika Adjour Khaled Cheikh Nebagha Zein el Arby Vetah Mohamed el Moktar Isselmou Brahim Vall Department of Geology Faculty of Sciences Ben Msik Hassan II University Casablanca Morocco Department of Geology Faculty of Sciences and Technology University of Nouakchott Al Asriya Nouakchott Mauritania National Agency for Geological Research and Mining Heritage Nouakchott Mauritania

The integration of remotely sensed data allowed the successful characterization of the mineral alteration zones of the Oudiane elkharoub area in the Northeastern part of Reguibat Shield using image transformation techniques. As both chemical and geochemical analyses showed significant Au, Ag, Cu, Pb, Mn, Cr, Ni, Th and Y anomalies, it’s very interesting to apply the remote sensing and GIS in mineral resources mapping. The remote sensing is a direct adjunct to the field, lithologic and structural mapping, and more recently, GIS has played an important role in the study of mineralization areas. The integration of several evidential maps highlighted the plausible areas with high concentrations of chlorite, epidote, kaolinite, calcite, alunite, hematite, illite and sulfur among other key mineral alterations that reflect the intensity of hydrothermal effects and the probable sites of ore bodies. The methodological approach integrates geological information acquired from Aster and Landsat 8 OLI/TIRS (Operational Land Imager/Thermal InfraRed Sensor) images and a multi-criteria GIS analysis. The superimposition of various lineament and hydrothermal alteration maps and the consideration of precious and base metal indicators allowed the zoning of sites likely to contain mineral concentrations. Remote sensing becomes an important tool for locating mineral deposits in its own right, when the primary and secondary processes of mineralization result in the formation of spectral anomalies. Reconnaissance lithological mapping is usually the first step of mineral resource mapping. This is complimented with structural mapping, as mineral deposits usually occur along or adjacent to geologic structures, and alteration mapping, as mineral deposits are commonly associated with hydrothermal alteration of the surrounding rocks. Ground truthing and laboratory studies including XRD analysis were utilized to verify the results.

关键词： Remote Sensing GIS ASTER Landsat 8 (OLI/TIRS) Structure Mineralization Alteration Mineral Lineament Reguibat Shield Oudiane elkharoub

An experimental investigation of transient cavitation control on a hydrofoil using hemispherical vortex generators

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Journal of Hydrodynamics 2021年第6期33卷 1139-1147页

作者： Ebrahim Kadivar Takaho Ochiai Yuka Iga ould el Moctar Ship Technology Ocean Engineering and Transport SystemsUniversity of Duisburg-EssenDuisburgGermany Institute of Fluid Scienece Tohoku UniversitySendaiJapan

Unsteady cavitation causes noise,damage,and performance decline in the marine engineering and fluid machinery ***,finding a method to control the cavitation and its destructive effects is important for the industrial *** this work,we proposed a passive method to control the unsteady behavior of transient cavitation at the medium Reynolds *** this aim,we performed an experimental study using a high-speed camera to analyze the effects of hemispherical vortex generators(VGs)on the cavitation dynamics around a hydrofoil *** addition,the pressure pulsations induced by the collapse of the cavity structures in the wake region of the hydrofoil were captured with a pressure transducer mounted on the wall downstream of the *** results showed that the instability behaviors of the cavity structures on the hydrofoil were mitigated using the proposed cavitation passive control *** addition,the pressure pulsations in the wake region of the hydrofoil were reduced *** can be concluded that the suppression of cavitation instabilities can improve the operating life and reliability of the marine and hydraulic systems.

关键词： Hydrodynamic cavitation cavitation passive control hemispherical vortex generators pressure pulsations high speed observation

Enhancing optical absorption in visible light of ZnO co-doped with europium and promethium by first-principles study through modified Becke and Johnson potential scheme

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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

Toxicology,biosynthesis,bio-control of aflatoxin and new methods of detection

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Asian Pacific Journal of Tropical Biomedicine 2016年第9期6卷 808-814页

作者： Mohamed Amine Gacem Aminata ould el Hadj-Khelil Laboratory of Protection of Ecosystems in Arid and Semi-Arid Area University of Kasdi Merbah Department of Biology Faculty of ScienceUniversity of Amar Tlidji

Mycotoxins and their derivatives since their discoveries and until the present time are behind unspecified economic and medical *** are classified according to their physical–chemical and toxicological characters in the most dangerous row of the *** aflatoxins are in part responsible,of irreversible medical disasters that are not easily manageable such as cancer of the liver and kidneys,and in the other part,of losses in the stored cereal *** on these crucial findings,monitoring of this toxin became imperative in post-harvest food products,during storage,during transformation chain and even during the long phases of *** of this toxin is delivered by detection methods using very advanced technologies to respond in the shortest possible *** addition,the knowledge of factors supporting the biosynthesis of aflatoxins such as the temperature,moisture content,concentration of nitrogen and carbon,and the molecules responsible for the genetic control of the synthesis will be reflected later in the choice of bio-control *** control is currently based on new strategies using the bioactives substances of the plants,the lactic bacteria and some strains of actinomycetes that have good inhibiting activity against aflatoxins with fewer side effects on *** the other hand,this brief review summarizes the results of new studies demonstrating the toxicity of the toxin,new detection methods and bio-control.

关键词： Mycotoxins Aflatoxins Cancer Biosynthesis Bio-controls Detection methods

Quantum Steganography via Greenberger-Horne-Zeilinger GHZ_4 State

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Communications in Theoretical Physics 2012年第4期57卷 577-582页

作者： A.el Allati M.B.ould Medeni Y.Hassouni Facultédes Sciences Département de PhysiqueLPT-URAC-13UniversitéMohammed V-Agdal.Av.Ibn BattoutaB.P.1014RabatMaroc The Abdus Salam International Centre for Theoretical Physics TriesteItaly Facultédes Sciences Laboratory of Mathematic Informatics and ApplicationsUniversitéMohammed V-Agdal.Av.Ibn BattoutaB.P.1014RabatMaroc

A quantum steganography communication scheme via Greenberger-Horne-Zeilinger GHZ 4 state is constructed to investigate the possibility of remotely transferred hidden ***,the multipartite entangled states are become a hectic topic due to its important applications and deep effects on aspects of quantum ***,the scheme consists of sharing the correlation of four particle GHZ4 states between the legitimate *** insuring the security of the quantum channel,they begin to hide the secret information in the cover of *** the scheme with the previous quantum steganographies,capacity and imperceptibility of hidden message are *** security of the present scheme against many attacks is also discussed.

关键词： quantum steganography GHZ4 entangled state quantum cryptography quantum communication

Multiple Solutions to the Problem of Kirchhoff Type Involving the Critical Caffareli-Kohn-Niremberg Exponent, Concave Term and Sign-Changing Weights

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Applied Mathematics 2017年第11期8卷 1703-1714页

作者： Mohammed el Mokhtar ould el Mokhtar Departement of Mathematics College of Science Qassim University Buraidah KSA

In this paper, we establish the existence of at least four distinct solutions to an Kirchhoff type problems involving the critical Caffareli-Kohn-Niremberg exponent, concave term and sign-changing weights, by using th... 详细信息

关键词： Kirchhoff Type Problems Critical Caffareli-Kohn-Niremberg Exponent Concave Term Sign-Changing Weights

Four Nontrivial Solutions for Kirchhoff Problems with Critical Potential, Critical Exponent and a Concave Term

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Applied Mathematics 2015年第14期6卷 2248-2256页

作者： Mohammed el Mokhtar ould el Mokhtar Departement of Mathematics College of Science Qassim University Buraidah Kingdom of Saudi Arabia

In this paper, we consider the existence of multiple solutions to the Kirchhoff problems with critical potential, critical exponent and a concave term. Our main tools are the Nehari manifold and mountain pass theorem.

关键词： Kirchhoff Problems Critical Potential Concave term Nehari Manifold Mountain Pass Theorem

On elliptic Problem with Singular Cylindrical Potential, a Concave Term, and Critical Caffarelli-Kohn-Nirenberg Exponent

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Applied Mathematics 2015年第11期6卷 1891-1901页

作者： Mohammed el Mokhtar ould el Mokhtar Department of Mathematics College of Science Qassim University Buraidah Kingdom of Saudi Arabia

In this paper, we establish the existence of at least four distinct solutions to an elliptic problem with singular cylindrical potential, a concave term, and critical Caffarelli-Kohn-Nirenberg exponent, by using the N... 详细信息

关键词： Singular Cylindrical Potential Concave Term Critical Caffarelli-Kohn-Nirenberg Exponent Nehari Manifold Mountain Pass Theorem

Five Nontrivial Solutions of p-Laplacian Problems Involving Critical Exponents and Singular Cylindrical Potential

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Journal of Physical Science and Application 2015年第2期5卷 163-172页

作者： Mohammed el Mokhtar ould el Mokhtar Departement of Mathemtics Qassim University BO 6644 Buraidah 51452 Kingdom of Saudi Arabia

In this paper, we establish the existence of at least five distinct solutions to a p-Laplacian problems involving critical exponents and singular cylindrical potential, by using the Nehari manifold, concentration-comp... 详细信息

关键词： Nehari manifold concentration-compacmess principle critical Hardy-Sobolev exponent singular cylindrical potential mountain pass theorem nontrivial cylindrical solution.