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Evaluation of the Level of Pollution by Heavy Metals of Market Garden Soils along the Chari River in Ndjamena: Case of the 9th and 7th Districts

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Agricultural sciences 2024年第8期15卷 939-961页

作者： Kotva Wana Mackaye Hassane Taisso Likius Andossa Béral Djétenbé laboratoire Gosciences Dpartement des Sciences de la Terre Facult des Sciences Universit de NDjamena NDjamena Chad laboratoire Gosciences Dpartement des Sciences de la Terre Facult des Sciences Universit de Mongo Mongo Chad laboratoire Sol et Environnement (laSEN) Dpartement des Sciences de la Terre Facult des Sciences Universit de Ngaoundr Ngaoundr Cameroun

The main aim of this study was to characterize the metal content of soils used for market gardening along the Chari river: the 7th and 9th districts of NDjaména. To achieve this, two sites were selected: Gassi and Walia, and two control sites (Gassi and Walia). A total of fifty (50) soil samples were taken (24 from the Gassi site, 24 from the Walia site and 2 as control soils) and then analyzed to determine a number of physico-chemical parameters (pH, OM and electrical conductivity) and heavy metal concentrations in the various soils. The TME content (As, Cd, Cu, Cr, Ni, Pb, Hg and Zn) of the soils was determined by plasma-coupled Atomic Emission Spectrometry. In order to assess the level of contamination in Gassi and Walia soils, the geoaccumulation index (GeoIndex), contamination factor and degree of contamination were calculated. Results for physico-chemical parameters revealed that pH ranged from acidic (4.6) to moderately neutral (6.5), electrical conductivity was higher in cultivated soils (mean 292.14 μs/cm) than in control soils (mean 149.33 μs/cm), and soils were rich in organic matter. Overall, heavy metal concentrations in cultivated soils were higher than in control soils. The pollution estimate shows that soils in the area have no moderate contamination. The increase in TME concentrations in cultivated soils is thought to be due to the input of agricultural inputs to the soil. However, these levels are below the Average shale reference and Canadian guidelines for agricultural soil quality. Principal component analysis shows that metals are positively and significantly correlated with each other, and negatively and moderately significantly correlated with each other.

关键词： Contamination Agricultural Soils City of N’Djaména ETM Gassi Walia

Petrographic and Geochemical Characters of Granites of the Banfora Belt, Burkina Faso (West Africa)

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International Journal of Geosciences 2024年第9期15卷 682-697页

作者： Abdoulaye Ouedraogo Seta Naba Hermann Ilboudo laboratoire Gosciences et Environnement (laGE) Dpartement des Sciences de la Terre Unit de Formation et de Recherche en Sciences de la Vie et de la Terre Universit Joseph KI-ZERBO Ouagadougou Burkina Faso Bureau des Mines et de la Gologie du Burkina (BUMIGEB) Ouagadougou Burkina Faso

The Banfora’s birimian greenstones belt is located in the western part of Burkina Faso (west Africa). Recent petrographic and lithogeochemical studies have highlighted plutons intruding the metasedimentary and metavolcanic series. These plutonic rocks are composed of leucogranites belonging to the so-called Ferkessedougou’s or Ferké’s batholith, granites, granodiorites, monzodiorites and quartz monzonites. From the lithogeochemical studies, these plutonic rocks have a calc-alkaline and peraluminous character. The rare earth elements spectra of the Ferké’s leucogranites let distinguished two sub-facies. One of the sub-facies is composed of quartz monzonite to granite, while the other is granitic sensu stricto. However, all these plutonic rocks were emplaced in a geodynamic context of subduction followed by collision.

关键词： Burkina Faso Banfora Greenstones Belt Plutons Geodynamic Context Subduction

Insight from Lithostructural and Aeromagnetic Data from the Léo Square degree, Central-Western Burkina Faso

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Open Journal of Geology 2024年第1期14卷 19-28页

作者： Adama Ouédraogo Yaméogo Pascal Ouiya Gounwendmanaghré Hubert Zongo Omar Akonyiré Abraham Seydoux Traoré Saga Sawadogo Séta Naba Unité de Formation et de Recherche en sciences et Technologies Département des Sciences de la Vie et de la Terre Université Norbert Zongo Koudougou Burkina Faso Unité de Formation et de Recherche en sciences de la Vie et de la terre Laboratoire Géosciences et Environnement (LaGE) Département des Sciences de la Terre Université Joseph Ki-Zerbo Ouaga Burkina Faso Ecole Normale Supérieure (ENS)/Institut des sciences et de Technologie (IST) Ouaga Burkina Faso Ecole Supérieure d’Ingénieries Université de Fada N’gourma Fada N’Gourma Burkina Faso

This study, carried out in the Léo square degree (west-central Burkina Faso) in the Palaeoproterozoic domain of the Man/Léo ridge, aims to define the shapes and positions of granitic plutons and the organisation of deformation structures using aeromagnetic data. These data have shown that there are small sub-circular granitic bodies to the north of the granitic masses in this region, and a large sub-circular granitic body to the south, around which are other smaller granitic bodies. The lineament map shows that the deformation structures are organised along three main directions and largely form these sub-circular plutonic bodies. We suggest that the granitic plutons are coalescent, pending identification of the internal structures of these granites to further refine the geodynamic model.

关键词： Burkina Faso Lineaments Belts Rocks Leo’s Leaf Granitoïd Airbornes Magnétics

Petrographic and Geochemical Characteristics of the Granitoids in the South of Godé (North of the Square degree of Léo-Burkina Faso, West Africa)

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International Journal of Geosciences 2024年第2期15卷 106-118页

作者： Adama Ouédraogo Yaméogo Hubert Gounwendmanaghré Zongo Pascal Ouiya Omar Akonyiré Abraham Seydoux Traoré Saga Sawadogo Séta Naba Unité de Formation et de Recherche en sciences et Technologies Département des Sciences de la Vie et de la Terre Université Norbert Zongo Koudougou Burkina Faso Unité de Formation et de Recherche en sciences de la Vie et de la terre Laboratoire Géosciences et Environnement (LaGE) Départe-ment des Sciences de la Terre Université Joseph Ki-Zerbo Ouaga Burkina Faso Ecole Supérieure d’Ingénieries Université de Fada N’gourma Fada N’Gourma Burkina Faso Ecole Normale Supérieure (ENS)/Institut des sciences et de Technologie (IST) Ouaga Burkina Faso

South of Godé, in the central-western region of Burkina Faso, granitoids of Paleoproterozoic age are similar to those of the Man/Leo shield. This study focused on the petrographic and geochemical characteristics of these granitoids, with the following results: 1) The tonalite that outcrops in the south-west of the study area belongs to the TTG group or first generation granitoids. They are most often ribboned at outcrop and have a geochemical signature close to that of Archean TTGs. Tonalite has a metaluminous character and the REE spectrum indicates that it may be derived from partial melting of basic magmatic rocks. 2) Biotite granites have no outcrop structure. They are weakly metaluminous to peraluminous and potassic to highly potassic. Their rare earth spectra indicate that they may be derived from the partial melting of TTG granitoids. 3) Geotectonic diagrams show that the granitoids studied to the south of Godé were emplaced in an active tectonic context similar to that of present-day subduction zones.

关键词： Burkina Faso Godé Man/Leo Shield Petrography Geochemistry Partial Melting Geotectonic Setting

Petrographic and Geochemical Characteristics of the Pouni Palaeoproterozoic Formations North of the Léo Square degree (Burkina Faso, West Africa)

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Open Journal of Geology 2024年第1期14卷 126-141页

作者： Adama Ouédraogo Yaméogo Pascal Ouiya Hubert Gounwendmanaghré Zongo Omar Akonyiré Abraham Seydoux Traoré Saga Sawadogo Séta Naba Unité de Formation et de Recherche en sciences et Technologies Département des Sciences de la Vie et de la Terre Université Norbert Zongo Koudougou Burkina Faso Unité de Formation et de Recherche en sciences de la Vie et de la terre Laboratoire Géosciences et Environnement (LaGE) Département des Sciences de la Terre Université Joseph Ki-Zerbo Ouaga Burkina Faso Ecole Normale Supérieure (ENS) Institut des Sciences et de Technologie (IST) Ouaga Burkina Faso Ecole Supérieure d’Ingénieries Université de Fada N’gourma Fada N’Gourma Burkina Faso

The Pouni area is made up of basalts belonging to the Boromo belt, lamprophyres and granitoids. These geological formations are similar to geological formations of the same type in other regions of the Palaeoproterozoic domain of the Man/Leo shield. This study, which focused on the petrographic and geochemical characteristics of these geological formations, led to the following main conclusions: The lamprophyres are basic plutonic rocks that cut through other geological formations. The basalt belongs to the northern part of the Borormo belt and is thought to be a relic of overthickened oceanic plateaus. There are two groups of granitoid rocks. The granodiorite has a geochemical signature close to that of Archean TTGs and is metaluminous in character. It has a low potassium content. The minor element and rare earth element spectra indicate that it could be derived from partial melting of basic magmatic rocks. Biotite granites are peraluminous and highly potassic. Minor element contents and rare earth spectra indicate that they could be derived from partial melting of felsic materials. Geotectonic diagrams show that the granitoids identified in the Pouni zone were emplaced in an active tectonic context, similar to that of present-day subduction zones.

关键词： Burkina Faso Dori Man/Léo Shield Petrography Geochemistry Partial Melting Geotectonic Context

Evaluation of a Rapid Diagnostic Test, Boson Biotech SARS CoV-2 Ag, for the detection of SARS-CoV-2 in Gabon

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Advances in Infectious Diseases 2024年第2期14卷 469-477页

作者： Samira Zoa Assoumou Ulrich Leger Davy Mouangala Ludovic Mewono Davy-Christ Angoune Ndong Guy Paterne Malonga Mbembo Nely Meungang Alain Moutsinga Elvyre Anita Mbongo Kama Rodrigue Mintsa Nguema Dpartement de Bactriologie-Virologie Universit des Sciences de la Sant Libreville Gabon laboratoire Professeur Daniel Gahouma Libreville Gabon departement des sciences de la vie et de la terre Ecole Normale Suprieure Libreville Gabon Centre de sant de Glass Libreville Gabon laboratoire National de Sant Publique Libreville Gabon Dpartement de Biologie et Ecologie Animale Centre National de la Recherche Scientifique et Technologique Libreville Gabon laboratoire decologie des Maladies Transmissibles (LEMAT) Universit Libreville Nord (ULN) Libreville Gabon

1) Background: Rapid and acurate diagnostic testing for case identification, quarantine, and contact tracing is essential for managing the COVID 19 pandemic. Rapid antigen detection tests are available, however, it is important to evaluate their performances before use. We tested a rapid antigen detection of SARS-CoV-2, based on the immunochromatography (Boson Biotech SARS-CoV-2 Ag Test (Xiamen Boson Biotech Co., Ltd., China)) and the results were compared with the real time reverse transcriptase-Polymerase chain reaction (RT-PCR) (Gold standard) results;2) Methods: From November 2021 to december 2021, samples were collected from symptomatic patients and asymptomatic individuals referred for testing in a hospital during the second pandemic wave in Gabon. All these participants attending “CTA Angondjé”, a field hospital set up as part of the management of COVID-19 in Gabon. Two nasopharyngeal swabs were collected in all the patients, one for Ag test and the other for RT-PCR;3) Results: A total of 300 samples were collected from 189 symptomatic and 111 asymptomatic individuals. The sensitivity and specificity of the antigen test were 82.5% [95%CI 73.8 - 89.3] and 97.9 % [95%CI 92.2 - 98.2] respectively, and the diagnostic accuracy was 84.4% (95% CI: 79.8 - 88.3%). The antigen test was more likely to be positive for samples with RT-PCR Ct values ≤ 32, with a sensitivity of 89.8%;4) Conclusions: The Boson Biotech SARS-CoV-2 Ag Test has good sensitivity and can detect SARS-CoV-2 infection, especially among symptomatic individuals with low viral load. This test could be incorporated into efficient testing algorithms as an alternative to PCR to decrease diagnostic delays and curb viral transmission.

关键词： SARS-CoV-2 Rapid Diagnostic Test Evaluation COVID-19 Antigen Performance

Structural Pattern Related to Gold Mineralization in the Essakane Area (Northern Burkina Faso, West African Craton)

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Open Journal of Geology 2024年第9期14卷 855-879页

作者： Marc desire Valea Benjamin Sawadogo Kalidou Traoré Urbain Wenmenga Naba Seta Benjamin Allou laboratoire Gosciences et Environnement (laGE) Dpartement des Sciences de la Terre Universit Joseph Ki-Zerbo Ouagadougou Burkina Faso Essakane Sarl IAMGOLD Corporation Ouagadougou Burkina Faso laboratoire de Godynamique et de Cartographie Universit des Sciences des Techniques et des Technologies de Bamako Bamako Mali

The finite deformation structures recorded in the Essakane area, located in the northeast corner of Burkina Faso, highlight three major compressive deformation phases, successively named D1, D2, and D3. The D1 event phase, trending NE-SW, is characterised by P1 folds and S1 axial plane schistosity. The D2 phase trending NW-SE is characterised by folds P2, schistosity (S2) and shear (C) planes. And the D3 phase trending NNE-SSW to N-S is characterised by P3 folds, crenulation microfolds and S3 spaced schistosity. It has also been noted that gold mineralizations are mainly hosted in quartz, carbonate, pyrite, and arsenopyrite veins. Structural interpretation indicates that these veins are organized into lenticular bodies that were formed during the first two deformation phases (D1 and D2). This suggests a strong structural control typical of orogenic gold concentrations.

关键词： Burkina Faso Essakane Shear Zone deformation Phases Orogenic Gold

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

Gold Mineralisation in the Intiédougou Prospect (Diébougou District) in Southwest Burkina Faso, West African Craton

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Journal of Minerals and Materials Characterization and Engineering 2024年第1期12卷 63-77页

作者： Yao Honoré Koffi Wendkouni Passecdé Pauline Zongo Nanema Mathieu Urbain Wenmenga Département de Géosciences UFR Sciences Biologiques Université Peleforo Gon COULIBALY Korhogo C&#244te d’Ivoire UFR sciences et Technologie Université de Ouahigouya Ouahigouya Burkina Faso Département des sciences de la terre UFR Sciences de la Vie et de la Terre Université Ouaga I Pr. Joseph KI-ZERBO Ouagadougou Burkina-Faso

The Intiédougou located in the Houndé Birimian greenstone belt has been the subject of several mining and geoscience studies that have led to the discovery of mineralized gold targets. One of these mineralized targets has prompted work that raises the issue of control factors for the gold mineralization of the prospect. The methodology used in this study combines a study of core drill hole data located in the area and laboratory studies. The Intiédougou sector is based on andesito-basaltic, andesitic interstratified volcanoclastite rocks and Tarkwaïen type detrital sedimentary rocks caught in a vice in the volcano-sedimentary unit. Lithostructural analysis of the sector shows that the subvolcanic rocks bearing gold mineralization are subjected to heterogeneous ductile to brittle deformations and affected by hydrothermalism evolving at stages marked by large fissure fillings. These hydrothermal phases evolve in the zones of expansion created by the brittle deformations that have contributed to the deposits of different types of gold-enriched sulphides. These different phases of hydrothermal destabilization generally of low degree accompany the tardi to post-eburnean brittle tectonics. This deformation system is favorable to the establishment of gold mineralization in the form of vein bodies. The overimposition of deformed and altered areas suggests a genetic relationship between deformation and hydrothermal activity. In conclusion, the mineralization of Intiédougou in vein styles, set up in a volcanic arc environment with a paragenesis of gold-pyrite deposit ± chalcopyrite would be controlled by the structural aspect and accompanied by hydrothermal alteration.

关键词： Intiédougou Prospect Shear Hydrothermal Tarkwaïan Gold Mineralization