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Open Journal of Geology 2023年第5期13卷 312-336页

作者： samba Cissokho Adinane Ahamada Abdoulaye Ndiaye Diomaye Yatte Papa Malick Ngom Department of Geology Faculty of Sciences and Technics Cheikh Anta Diop University of Dakar (UCAD) Dakar Senegal

The Bangaani area is located in the northwestern part of the Karthala Massif on the island of Grande Comore, about 10 km from the capital Moroni. It is essentially constituted of basalt plateaus outcropping in the form of pahoehoe and aa lava flows or in the form of massive vesicular or non vesicular basalt flows. Petrographic analysis of the massive basalts studied shows a porphyritic microlitic texture marked by the successive crystallization of olivines, opaque minerals, clinopyroxenes and plagioclases in a relatively abundant mesostasis. This crystallization sequence is typical of a high pressure environment corresponding to primary alkaline magmas. The geochemical study of major and trace elements shows that the basalts studied are under saturated in silica (47.24%) but rich in alkali (2.26%) and titanium (2.66%). They correspond to intraplate alkaline basalts of type oceanic island basalts (OIB) and present a primary character marked by relatively high contents of magnesium (6.69%), chromium (151.23 ppm), nickel (107.53 ppm) and scandium (27.15 ppm). The REE and multi-element diagrams confirm that the Karthala basalts are alkaline basalts of type OIB by their enrichment in LILE and their depleted character in HREE and HFSE. In terms of isotopic ratios, they are comparable to HIMU and EM I.

关键词： Bangaani Karthala Comore Alkaline Basalts OIB

Effect of RF power on the structural and optical properties of ZnS thin films prepared by RF-sputtering

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Journal of Semiconductors 2018年第12期39卷 26-31页

作者： C.M.samba Vall M.Chaik H.Ait Dads H.El Aakib M.Elyaagoubi M.Aggour A.Outzourhit Laboratory of Nanomaterials for Energies and Environments Faculty of Sciences Semlalia Cadi Ayyad University Laboratory of Renewable Energy and Environment Faculty of Science Kenitra Ibn Tofail University

Zinc sulphide(ZnS) thin films have grown on glass and Si substrates by reactive cathodic radio frequency(RF) sputtering. The RF power was varied in the range of 100 to 250 W, while the deposition time is set at75 min. The optical, structural, and morphological properties of these thin films have been studied. The optical properties(mainly thickness, refractive index,absorption coefficient, and optical band gap) were investigated by optical transmittance measurements in the wavelength range of ultraviolet-visible-near infrared spectroscopy and spectroscopy infrared with Fourier transform. Fourier(FT-IR) and XRD analysis indicated that all sputtering ZnS films had a single-phase with a preferred orientation along the(111) plane of the zinc sphalerite phase(ZB). The crystallite size ranged from 11.5 to 48.5 nm with RF power getting a maximum of 200 W. UV-visible measurements exhibited that the ZnS film had more than 80% transmission in the visible wavelength region. In addition, it has been observed that the band gap energy of ZnS films is decreased slightly from 3.52 to 3.29 eV, and as the RF power is increased, the film thickness increases with the speed of deposit growth. Scanning electron microscopy observations revealed the types of smooth-surfaced films. The measurements(FT-IR) revealed at wave number1118 and 465.02 cmabsorption bands corresponding to the symmetrical and asymmetric vibration of the Zn-S stretching mode. X-ray reflectometry measurements of ZnS films have shown that the density of the films is(3.9 g/cm~3) close to that of solid ZnS.

关键词： ZnS thin films by sputtered RF-sputtering ZnS ZnS buffer layer for solar cell

Physico-Chemical and Petrographic Characterization of Carbonated Rocks of Mintom (South-Cameroon) and Their Potential Uses

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International Journal of Geosciences 2016年第5期7卷 775-783页

作者： Zo’o Zame Philémon Mpakam Hernanie Grelle samba Assomo Philippe Department of Earth Sciences Faculty of Sciences University of Yaoundé I Yaoundé Cameroon The Higher Institute of the Sahel University of Maroua Maroua Cameroon

The characterization of carbonated rocks of Mintom allowed identifying three features (massive limestone, banded limestone and dolomite). Samples taken in these features were subjected to the physico-chemical analyses and to the mechanical tests. The results obtained show a convergence in the mineralogical composition in particular in the calcareous features (smectite, micas and calcite);the dolomite feature being mainly constituted by dolomite associated with the smectite. The chemical composition allows finding contents raised in CaO, in all the samples. However, in the dolomite and the banded limestone, the concentrations in MgO and in SiO2 are also important. The mechanical properties showed a good compression resistance for the massive limestone and the dolomite, the mechanical behavior of the banded limestone being low. The exploitation of these results allows recommending carbonated rocks of Mintom in the production of the clinker, agricultural amendments and in the constructions of the civil engineering.

关键词： Mintom Carbonated Rocks Characterization Physico-Chemical Petrographic

The Impact of Climate Variabilities on the Water Resources of Nyong River (Cameroon) during Few Anterior Decades

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International Journal of Geosciences 2016年第4期7卷 459-469页

作者： Mpakam Hernanie Grelle Ombolo Auguste samba Assomo Philippe Bineli Ambomo Etienne The Higher Institute of the Sahel University of Maroua Maroua Cameroon Faculty of Science University of Yaoundé I Yaounde Cameroon

The Nyong River is situated in south Cameroon. The study of the impact of climate change on the water resource of the River shows that its precipitations and flow rate are decreasing. This negative effect is reinforcing by the fact that the water of the River is collected to feed the population of Yaoundé, the political capital of Cameroon and its environs. Given that no action can stop the variability of climate factors, it is necessary to ameliorate the management of water resource of Nyong River.

关键词： Climate Variability Water Resource Nyong River Impact

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外星人——罗纳尔多

希望月报(下半月) 2002年第19期 34-38页

作者： samba

罗纳尔多是这届世界杯的风云人物,球迷们关心现在的他,同时也关心往昔的他,青少年时的罗纳尔多是怎样的呢?请看下文——用报纸做足球小罗纳尔多童年时光很贫困,但很幸福,家庭和睦使他能在一个充满危险的社会里健康成长。很多人为了出人... 详细信息

罗纳尔多是这届世界杯的风云人物,球迷们关心现在的他,同时也关心往昔的他,青少年时的罗纳尔多是怎样的呢?请看下文——用报纸做足球小罗纳尔多童年时光很贫困,但很幸福,家庭和睦使他能在一个充满危险的社会里健康成长。很多人为了出人头地,为摆脱贫困采取不正当手段,甚至铤而

关键词：罗纳尔多席尔瓦世界杯弗拉门戈锦标赛室内足球外星人

Assessment of Geotechnical Properties of Lateritic Gravels from South-Cameroon Road Network

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International Journal of Geosciences 2017年第8期8卷 949-964页

作者： Philémon Zo’o Zame Philippe samba Assomo Josephine Nchekwube Onwualu Department of Earth Sciences Faculty of Science University of Yaoundé I Yaoundé Cameroon Department of Geology University of Port Harcourt Port Harcourt Nigeria

The southern road network covers the eastern, central and southern administrative regions;its linear network of national and provincial roads is about 5 620 km. It was the subject of a survey for the identification of lateritic quarries. To this effect, 144 sites have been discovered. The collected lateritic gravels were subjected to identification analyzes (Granulometry, Atterberg Limits, densimetry, water content) and geotechnical characterization tests (Proctor Modified, CBR at 95% OPM). The obtained results show that the grain size has a great percentage of gravels (>60%) followed by sand. Stones silt and clay particles are poorly represented. The samples show a high plasticity in conformity with Casagrande’s plasticity diagram. The density values of the solid particles (γ s) are quite stable in the studied area and vary between 26 and 29 KN/m3 for a natural water content comprised between 10% and 20%. The modified proctor test gives an optimal water value (Wop %) comprised between 8% and 12%. Dry density values (γ d) varied between 18 and 30 KN/m3. The bearing capacity of the materials is good (30 < CBR < 90). These results permit the recommendation of the studied materials as foundation layers of roads for traffic classes between T1-T4.

关键词： Properties Lateritic Gravel Tests Geotechnical Characterization Foundation Layers

Pulmonary Hypoplasia: A Rare Cause of Chronic Cough in TB Endemic Area

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Open Journal of Respiratory Diseases 2019年第1期9卷 18-25页

作者： Ouattara Khadidia Kanoute Tenin Baya Bocar Soumaré Dianguina Kamian Youssouf Mama Sidibé Youssouf Fofana Aminata Traoré Mohamed Maba Guindo Ibrahim Sidibe Fatoumata Dakouo Aimé Paul Sanogo Fatoumata Bintou Bamba Salimata Coulibaly Lamine Yossi Oumar kone Drissa samba Toloba Yacouba Department of Pneumology University Teaching Hospital of Point G Bamako Mali Department of ENT Secondary Hospital “Luxembourg” Bamako Mali Department of ENT Nianakoro Fomba Hospital Ségou Mali Department of Radiology Hospital of Mali Bamako Mali

Pulmonary hypoplasia is a rare disease characterized by a defect of lung development more often unilateral. The diagnosis requires several exams to eliminate other causes of pulmonary retraction. We report two cases at the department of pneumophtisiology of the University Teaching Hospital of Point G. The first case is a young adult who was complaining of a chronic cough. Etiological investigation required several exams including spirometry and Computed tomographic scan (CT scan). After elimination of all suspected causes of pulmonary opacity, the diagnosis of pulmonary hypoplasia was retained. The second case is a 2-year-old girl who was born with congenital cardiopathy whose respiratory complications were increasing during her childhood and respiratory explorations discovered pulmonary agenesis. Pulmonary hypoplasia is rare in our medical practice, but attention must be drawn to a retractile pulmonary opacity in young age after elimination of all infectious causes in TB endemic area.

关键词： A Chronic Cough Pulmonary Hypoplasia Bamako

An Explanation of the Black Color of River Nyong Water’s and Associated Alluviums (Cameroon)

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International Journal of Geosciences 2015年第4期6卷 388-392页

作者： samba Assomo Philippe Chi Cheyneysu Emmanuel Toussaints Kamgang Kabeyene Beyala Veronique Faculté des Sciences Université de Yaoundé I Yaoundé Cameroun Organisme Environnemental MIEUX-ETRE Douala Cameroun Ecole Normale Supérieur Université de Yaoundé I Yaoundé Cameroun

The River Nyong is situated in Akonolinga (central-south of Cameroon). In order to search for raw materials in ceramic use, samples of alluvium obtained from the deposits in the Nyong River clays have been studied. The results obtained show that, the samples contain important quantity of organic matter and the soil is acidic .These two parameters are necessary to understand the origin of the characteristic color of alluvium and water of the River Nyong.

关键词： Nyong River Black Color Akonolinga Alluvium Water

Modelling and Optimisation of Copper Adsorption in Solution by the Response Surface Method

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Advances in Chemical Engineering and Science 2023年第1期13卷 36-49页

作者： Kalidou Ba Alpha Ousmane Toure samba Ndiaye Moussa Diop Falilou Mbacke Sambe Laboratory of Water Energy Environment and Industrial Processes (LE3PI) Higher Polytechnic of Dakar (ESP) Cheikh Anta Diop University (UCAD) Dakar Senegal

Copper is considered a heavy metal that can be toxic at certain concentrations and its presence in water is a potential threat to public health. These heavy metals also contribute to a remarkable degradation of the environment, hence the need for effective treatment methods to remove them. In this study, a mixture of titaniferous sand and calcium silicate was used as adsorbent material to eliminate copper in solution. The calcium silicate was synthesised from fluosilicic acid, which is a by-product of phosphoric acid manufacture. The titaniferous sand is a residue from a mining industry. Both adsorbents were characterised by infrared spectroscopy and X-ray fluorescence to determine their compositions and physicochemical properties. The response surfaces, through the Box-Behnken model, were used to model and optimise various adsorption parameters, namely initial copper concentration (A: 60 - 200 mg/L), adsorbent dose (B: 0.1 - 0.6 g) and pH (C: 4 - 10). The copper removal efficiency (98.92%), after statistical analysis, was obtained under the following optimal conditions: an adsorbent dose of 0.55 g, an initial copper concentration of 197.25 mg/L and a pH of 9.85. The study of the effects of the operating parameters showed that they had a positive effect on the copper removal efficiency.

关键词： Adsorption Calcium Silicate Copper Response Surface Titaniferous Sand

Impact of Extraction on Biochemical Properties and Antioxidant Potential of Momordica charantia L. Seeds’ Oil

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Food and Nutrition Sciences 2022年第2期13卷 147-164页

作者： Balde samba Ayessou Nicolas Cyrille Khadim Niane Bou Ndiaye Mady Cisse Codou Mar Diop Centre d’Etude sur la Sécurité Alimentaire et les Molécules fonctionnelles (CESAM) Université Cheikh Anta DIOP de Dakar Fann Sénégal

In this study, the influence of provenance and extraction methods on the physicochemical properties and the antioxidant potential of M. charantia seeds oil were evaluated. The oil is obtained on the one hand by cold extraction with hexane and on the other hand by hot extraction with soxhlet. The results obtained show that the extraction yield is significantly impacted by the extraction methods and the origin of the seeds. In addition, the soxhlet extraction gives a higher oil yield (32.07 ± 0.01). Cold extraction has made it possible to obtain oils with less attenuated physicochemical characteristics. Indeed, the acid numbers are high in the oils extracted by soxhlet (5.92 ± 0.25;4.25 ± 0.62 and 13.86 ± 0.83) than in those cold extracted with very low peroxide for all the oils obtained. On the other hand, the iodine and refractive indices are high in oils obtained cold (91.58 ± 0.85;100.74 ± 0.03 and 102.08 ± 0.28) (1.53 ± 0.01;1.52 ± 0.01 and 1.52 ± 0.01) with low saponification indices. The polyphenol concentrations and the anti-free radical activity are higher with the oils obtained cold (0.086 ± 0.001;0.08 ± 0.000 and 0.09 ± 0.01 mgEAG/g of oil) and (DPPH) (55.75% ± 1.16%;55.03% ± 0.72% and 56.35% ± 0.45%). The color parameters (L*, a* and b*) of the different oils extracted also vary depending on the extraction method used. Principal Component Analysis (PCA) and correlation analysis were performed on the physicochemical properties and the antioxidant potential of the extracted oils. Therefore, the results suggest cold extraction to obtain a good quality and oxidation resistant oil.

关键词： Momordica charantia Oil Antioxidant Potential Extraction