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Differential Pulse Voltammetric Simultaneous Determination of Paracetamol and Omnipaque on Boron Doped Diamond Electrode: Application to Natural Tomato, Carrot, Cucumber Juices and Wastewater
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作者 Koffi Konan Martin Sadia Sahi Placide +4 位作者 Kouadio Brou Albert Gnamba Corneil Quand-Même Fofié Thiery Auguste Appia Koffi Konan Sylvestre Lassiné Ouattara 《American Journal of Analytical Chemistry》 2023年第10期434-450,共17页
This article describes the use of a boron-doped diamond electrode (BDDE) as an electrochemical sensor for the simultaneous determination of omnipaque (OMP) and paracetamol (PCM) in perchloric acid medium (HClO4 0.1 M)... This article describes the use of a boron-doped diamond electrode (BDDE) as an electrochemical sensor for the simultaneous determination of omnipaque (OMP) and paracetamol (PCM) in perchloric acid medium (HClO4 0.1 M) and in complex matrices such as tomato, carrot and cucumber juices and waste water from the Treichville University Hospital. Voltammetric studies allowed us to have well-defined oxidation peaks at distinct potentials of OMP (E = 0.5 V/SCE) and PCM (E = 0.7 V/SCE). Under optimized conditions, well-defined quantities of OMP and PCM, introduced simultaneously by metered additions, gave linear responses in concentration ranges of 259.8 - 467.2 μM for OMP and 58.73 - 116.3 μM PCM. The detection limits obtained are 7.23 μΜ and 3.6 μΜ respectively for OMP and PCM with recovery rates between 85.8% ± 0.1% and 92.6% ± 0.1% for OMP and between 99.9% ± 0.1% and 101.2% ± 0.4% for the PCM. This technique has been successfully used to simultaneously detect these pharmaceuticals in these complex environments. It allows recovery of OMP and PCM respectively up to 97.5% ± 0.0% and 91.6% ± 0.3% in tomato juice;100.0% ± 0.0% and 95.2% ± 0.2% in carrot juice;101.4% ± 0.1% and 97.3% ± 0.3% in cucumber juice;100.1% ± 0.9% and 100.9% ± 0.1% in wastewater. The relevance of this technique for the simultaneous detection of OMP and PCM in tomato, carrot, cucumber juices and in waste water can be studied in the context of the contamination of certain fruits and vegetables by the substances organic pharmaceuticals released into the environment without prior treatment. 展开更多
关键词 OMNIPAQUE Paracétamol Differential Pulse Voltammetry Boron Doped Diamond Electrode
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Yield, Growth and Vegetative Development Parameters Response of Dry Beans to Organic and Inorganic Fertilizers and Biofertilizer
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作者 Noupé Diakaria Coulibaly André Gabazé Gadji +5 位作者 Serge Hervé Kimou Christian Landry Ossey Lassina Fondio Mako François De Paul N’Gbesso Aya Félicité N’Gaza Louis Butare 《Agricultural Sciences》 2023年第12期1688-1701,共14页
As part of the promotion of common bean cultivation, fertilization methods will have to be proposed to growers. The aim of this study is therefore to develop a technical itinerary for dry bean fertilization. To this e... As part of the promotion of common bean cultivation, fertilization methods will have to be proposed to growers. The aim of this study is therefore to develop a technical itinerary for dry bean fertilization. To this end, different types of chemical and organic fertilizers were evaluated on three dry bean varieties (HARI25/GHA19, HARI35/GHA19 and HARI36/GUI21). Seven (7) doses of chemical and organic fertilizers were used, including two controls (D0 with no fertilizer and D1, the reference dose using NPK base and cover fertilizers in the form of urea). The fertilization trial was set up as a Split-Plot design, with variety as the primary factor and dose as the secondary factor. The experiment was repeated three (3) times. The results showed that vegetative development parameters and fruit set rate varied according to the variety studied. For yield and its components, the treatments had a significant effect. Indeed, the response of varieties to fertilizers was specific. For each variety used, the optimum yield was obtained with a different treatment, thus highlighting the genotype effect of the dry bean varieties studied. Among the treatments tested, D4 (5 t organic fertilizer/ha) performed best in all three varieties, generating yield increases of 20%, 46% and 91% respectively. 展开更多
关键词 Dry Bean VARIETY Chemical Fertilizer Organic Matter BIOFERTILIZER
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Kinetic and Thermodynamic Study of the Elimination of Remazol Black on Activated Carbon Based on Ricinodendron heudelotii Shells
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作者 Kouakou Yao Urbain Kambiré Ollo +2 位作者 Eroi N’goran Sévérin Koné Yétchié Tchonrontcha Trokourey Albert 《Journal of Materials Science and Chemical Engineering》 2023年第9期1-20,共20页
Activated carbon made from the shells of Ricinodendron heudelotii was used to remove the remazol black dye in aqueous solution. The results of the characterization of this carbon revealed that it is microporous, with ... Activated carbon made from the shells of Ricinodendron heudelotii was used to remove the remazol black dye in aqueous solution. The results of the characterization of this carbon revealed that it is microporous, with a basic global surface (0.337 mmol/L) and a specific surface of 612 m<sup>2</sup>/g. The prepared carbon therefore has excellent adsorbent properties. Kinetic and thermodynamic studies were carried out to describe the adsorption mechanism of remazol black on this carbon. It appears from this study that the pseudo-second-order kinetic model is the best suited to describe this adsorption phenomenon with an equilibrium time of 200 min. The adsorption equilibrium study revealed that Langmuir and Freundlich models can help to describe the adsorption process. We note that the optimum pH and optimum mass for the removal of 20 mg/L of remazol black are 3 and 0.25 g, respectively. This carbon made it possible to eliminate more than 98% of the remazol dye in aqueous solution. The thermodynamic study revealed that the adsorption is of the physisorption type, spontaneous and endothermic. 展开更多
关键词 Activated Carbon Ricinodendron heudelotii Dye Removal Optimization Adsorption Isotherm
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Study and Comparison of Swelling and Compressibility Characteristics of Crumb Marl, Flaky Marl with Attapulgite and Sandy Clay from the Diamniadio Urban Pole at the Oedometer
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作者 Khadim Faye Fatou Samb +1 位作者 Yves Berthaud Pape Sanou Faye 《Geomaterials》 2023年第3期61-70,共10页
In Senegal, the Diamniadio, Sebikhotane and Bargny sector contains clay soils that are problematic for construction. In order to have more information on the behavior of the clay soils of Diamniadio, free swelling tes... In Senegal, the Diamniadio, Sebikhotane and Bargny sector contains clay soils that are problematic for construction. In order to have more information on the behavior of the clay soils of Diamniadio, free swelling tests followed by load-discharge cycles were carried out according to standard NF P 94-090-1. These tests were carried out using an Oedometric device on the three samples from the study site (sandy clays with calcareous concretion, marls with crumbs and laminated marls with attapulgite) to apprehend their swelling aspects in saturated conditions. For the free swelling test, a determination of the different swelling phases will be carried out followed by a comparison of the rate of evolution of the phases for the three samples from the site. In the same vein, the compressibility characteristics of the samples will also be provided from load-unload Oedometric tests. Thereafter, we proceed to a comparison of the void index at the initial state of the samples after two charge-discharge cycles and the influence of the cycles on the reorganization of the internal structure of the samples. These studies will provide more information on the swelling behavior of Diamniadio soils in the presence of water. 展开更多
关键词 Clay Swelling Expansive Soil Evolution of The Swelling Compressibility Coefficient Charge-Discharge Cycle
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Properties and Characterization of Two Clays Raw Material from Mountain District (West of Côte d’Ivoire) for Use in Low-Carbon Cements
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作者 Wedjers Max Robin Manouan Bi Irié Hervé Gouré Doubi +3 位作者 Lébé Prisca Marie-Sandrine Kouakou Atta Kouamé Brice Koffi Alfred Niamien Kouamé Namory Méité 《Advances in Materials Physics and Chemistry》 CAS 2024年第8期137-145,共9页
This work was devoted to the study of the physico-chemical properties of two clay minerals from the Mountain District (West Côte d'Ivoire) referenced ME1 and ME2. These samples were characterized by the exper... This work was devoted to the study of the physico-chemical properties of two clay minerals from the Mountain District (West Côte d'Ivoire) referenced ME1 and ME2. These samples were characterized by the experimental techniques, such as X-ray diffraction (XRD), Infrared spectroscopy (IR), Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES), Differential Thermal Analysis and Thermogravimetry (DTA-TG), Brunauer, Emett and Teller method (BET), laser particle size analysis and Scanning Electron Microscope (SEM). The main results of these analyses reveal that the two clay samples mainly contain quartz (52.91% for ME1 and 51.72% for ME2), kaolinite (36.60% for ME1 and 41.6% for ME2) and associated phases, namely goethite and hematite (13.47% for ME1 and 11.00% for ME2). The specific surface values obtained for samples ME1 and ME2 are 34.78 m2/g and 29.18 m2/g respectively. The results obtained show that the samples studied belong to the kaolinite family. After calcination, they could have good pozzolanic activity and therefore be used in the manufacture of low-carbon cements. 展开更多
关键词 QUARTZ KAOLINITE Mountain District Low-Carbon Cements
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Study of the Biological Quality of the Water in the Manantali Dam Reservoir: Analysis of the Fish Fauna and Plankton Communities
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作者 Joseph Mbeur Faye Saïdou Ndao Louis Eugène Victor Sambou 《Journal of Agricultural Chemistry and Environment》 2024年第1期100-114,共15页
The aim of this study of the Manantali dam reservoir is to investigate the biological quality of the water through inventories and analysis of the ichthyofauna and planktonic communities (zooplankton and phytoplankton... The aim of this study of the Manantali dam reservoir is to investigate the biological quality of the water through inventories and analysis of the ichthyofauna and planktonic communities (zooplankton and phytoplankton). Inventories of ichthyofauna and plankton communities were carried out quarterly from 2003 to 2022. The fish populations studied on the basis of bioindicators (species richness, diversity index, equitability index, diversification index) identified 29 species belonging to 10 families. The Cichlidae family is the most represented, while the Schilbeidae and Tetraodontioae families are less represented in terms of number of species. The species Hydrocynus forskalii and Brycinus nurse with relative abundances of 40.12% and 21.4% respectively, both from the family Alestidae, are the most abundant. The species H. forskalii has a frequency of occurrence of 100%. The specific diversity index of 2.9 and the equitability index of 0.6 show an average diversity of fish species. The diversification index of 2.9 indicates a theoretical number of habitats of 2 to 3. The planktonic community is made up of zooplankton and phytoplankton. The inventory of zooplankton shows the presence of 28 zooplankton species belonging to 9 families of the three zooplankton groups Rotifera, Cladocera and Copepoda. Analysis of the frequencies of occurrence of the various taxa showed that the characteristic species of Lake Manantali are the omnipresent rotifers Keratella cochlearis, Keratella quadrata and Trichocerca chattoni. For phytoplankton, the inventories carried out show the presence of 65 species belonging to 5 families (Chlorophycees, Diatomees, Dinophycees, Chrysophycees and Cyanophycees). An analysis of the frequency of occurrence of the various taxa shows that the characteristic species of Lake Manantali are Chlorophycees, with 7 species: Desmidium baileyi, Micrasterias alata, Sphaerocystis schroeteri, Spondylosium sp., Staurastrum heimii, Staurastrum subanchora, Staurodesmus wandae;Diatoms, with one species: Navicula sp. and Cyanophycees, with one species: Microcystis aeruginosa. 展开更多
关键词 INVENTORY Fish ZOOPLANKTON PHYTOPLANKTON Diversity Manantali
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Management of Significant Environmental Aspects and Impacts in Accordance with the ISO 14001:2015 Standard during the Operation and Maintenance Phase of Senegal River Basin Development Authority Hydroelectric Works and Facilities: The Case of Manantali Dam
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作者 Joseph Mbeur Faye Saïdou Ndao Louis Eugène Victor Sambou 《Journal of Geoscience and Environment Protection》 2024年第10期89-110,共22页
This study aims to determine the environmental aspects and impacts of the phase relating to the operation of Manantali’s hydroelectric structures and facilities according to the requirements of the ISO 14001 version ... This study aims to determine the environmental aspects and impacts of the phase relating to the operation of Manantali’s hydroelectric structures and facilities according to the requirements of the ISO 14001 version 2015 standard. To do this, the mapping of the different work areas made it possible to identify all the activities within the framework of the farm. Based on the mapping, environmental measurements made including noise level, brightness, electric and magnetic fields, total particles, PM10, PM2.5, PM1 showed the work areas with the exposure limit values exceeded. The inventories of the waste produced show eighteen (18) types of waste, 67% of which are special industrial waste (SIW), 28% are ordinary industrial waste (OIW) and 5% are inert industrial waste (IIW). The identification and assessment of environmental aspects and impacts made it possible to determine sixteen (16) positive and negative significant environmental aspects (ESAs). The positive AES must be maintained, and for the negative ones, mitigation and mitigation measures must be put in place in order to manage them effectively. This will ultimately improve environmental management in the operation of hydroelectric structures and facilities. 展开更多
关键词 Manantali Environmental Aspect Environmental Impact Waste Mitigation and Mitigation Measures
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Comparative Study of Physico-Chemical and Biological Water Quality Upstream and Downstream of the Manantali Dam and Hydropower Plant from 2019 to 2023
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作者 Joseph Mbeur Faye Saïdou Ndao Louis Eugène Victor Sambou 《Journal of Geoscience and Environment Protection》 2024年第10期111-131,共21页
The comparative study is designed to monitor the physico-chemical and biological quality of the water upstream and downstream of the Manantali hydroelectric dam. The physico-chemical parameters are sampled at 3 measur... The comparative study is designed to monitor the physico-chemical and biological quality of the water upstream and downstream of the Manantali hydroelectric dam. The physico-chemical parameters are sampled at 3 measuring points located at Station 1 of the dam’s reservoir, immediately downstream of the dam and hydroelectric power station at the level of the damping basin, and at the Bafing-Bakoye confluence at Bafoulabe (Bafing side), the biological parameter (ichthyological fauna) is characterized by ichthyological inventories of landings in the various fishing camps around the reservoir and at the Mahina market (Bafing side). The study assesses the environmental impact of hydroelectric structures and facilities on the physico-chemical and biological quality of the water. Physical parameters such as temperature, conductivity, pH, turbidity and chemical parameters such as dissolved oxygen, nitrite, nitrate, manganese, hydrogen sulfide, ammonium, iron, silica and phosphorus are measured in order to identify the various variations existing between the different measurement points. Analysis of the values obtained shows very high similarities between the various measuring points, and most parameters comply with WHO standards, with the exception of turbidity, manganese, hydrogen sulfide and iron. These data attest to good water quality, allowing normal development of flora and fauna with a low level of degradation. Comparative analysis of the ichthyological fauna shows the existence of 34 species of fish belonging to 11 families at the fishing camps around the Manantali dam reservoir, and 37 species belonging to 12 families at Mahina on the Bafing River. At Mahina on the Bafing, the specific composition of the catches is characterized by the presence of the Claroteidae family and four species (Alestes sp., Brycinus leuciscus, Auchenoglanis occidentalis, Distichodus engycephalus) not recorded at the camps. In contrast, all the fish families recorded in the camps are present in Mahina, and only one species (Hydrocynus brevis) is absent from the Mahina landings. The difference in species richness could be explained by the upwelling of some fish from the Bakoye to the Bafing at the confluence. The Shannon diversity index of 4.07 at Mahina is higher than the 2.98 recorded at camp level, and the equitability index of 0.78 at Mahina and 0.58 at the camp level indicate average diversity and the non-dominance of one species over the others. The diversification index values of 3.09 and 3.08 at camp level and Mahina respectively show that the number of theoretical habitats is three. 展开更多
关键词 Manantali Dam Physical Parameters Chemical Parameters Fish Fauna
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Intra-Seasonal Variability of Aerosols and Their Radiative Impacts on Sahel Climate during the Period 2000-2010 Using AERONET Data 被引量:4
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作者 Mamadou Simina Drame Moctar Camara Amadou T. Gaye 《International Journal of Geosciences》 2013年第1期267-273,共7页
This paper presents a study using in situ measurements (AERONET data) to characterize the intra-seasonal variability of aerosols and their shortwave radiative impacts on Sahel (11N - 18N and 20W - 15E) climate using a... This paper presents a study using in situ measurements (AERONET data) to characterize the intra-seasonal variability of aerosols and their shortwave radiative impacts on Sahel (11N - 18N and 20W - 15E) climate using a long time series (2000 to 2010) from AERONET data. We first used the MISR aerosol optical depth (AOD) averaged between 2000 and 2010 to identify dust maxima regions. They are mainly located over Eastern Mauritania-Northern Mali and Eastern Niger-Western Tchad (near the Bodele depression). Moreover the aerosol loading is stronger during the spring (MAM) and particularly during the summer (JJA). The analysis of AERONET data at 4 Sahelian stations (Dakar, Agoufou, Banizoumbou and Ouagadougou) shows that Sahel is under dust influence all year long. The dust season is mainly located between March and October, with two peaks of AOD recorded in March and June;while the maximum of biomass burning activity is recorded in winter (December to February). The radiative forcing of aerosols on the Sahelian climate results mainly in a cooling as well as at the surface than at the top of the atmosphere (TOA) but the forcing is stronger at the surface and particularly during the summer (JJA) and spring (MAM) periods. Although there is not a sharp difference between DJF and SON periods from a station to another one when considering the aerosol loading (AOD), the radiative forcing is stronger at the surface and weaker at the TOA during DJF for most stations. The analysis of the force effectiveness (ratio between AOD and the radiative forcing) suggests that the BOA radiative forcing is mainly influenced by the nature of aerosols. 展开更多
关键词 AERONET Aerosol Optical Depth RADIATIVE FORCING
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Experimental and Theoretical Investigations on Copper Corrosion Inhibition by Cefixime Drug in 1M HNO<sub>3</sub>Solution
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作者 N’guessan Yao Silvère Diki Nagnonta Hippolyte Coulibaly +1 位作者 Ollo Kambiré Albert Trokourey 《Journal of Materials Science and Chemical Engineering》 2021年第5期11-28,共18页
Cefixime, a third-generation semi-synthetic cephalosporin antibiotic was used as a copper corrosion inhibitor in 1M HNO<sub>3</sub> solution. The study was conducted through the weight loss technique at 29... Cefixime, a third-generation semi-synthetic cephalosporin antibiotic was used as a copper corrosion inhibitor in 1M HNO<sub>3</sub> solution. The study was conducted through the weight loss technique at 298 - 318 K and theoretical studies based on quantum chemistry. The studied drug inhibited the corrosion of copper in 1M HNO<sub>3</sub> over the cefixime concentration range (0.02 - 2 mM). The inhibition efficiency increased with an increase in the inhibitor concentration to reach 91.07% at 2 mM, but decreased with an increase in temperature. The thermodynamic functions related to the adsorption of cefixime on the copper surface and that of the metal dissolution were computed and analyzed. The results point out spontaneous adsorption, mainly through a physisorption mechanism following Langmuir adsorption isotherm model and an endothermic dissolution process. Quantum chemical calculations were also performed at B3LYP level with 6-31G (d, p) basis set and lead to molecular descriptors such as E<sub>HOMO</sub> (energy of the highest occupied molecular orbital), E<sub>LUMO</sub> (energy of the lowest unoccupied molecular orbital), Δ<i>E</i> (energy gap) and <i>μ<span style="white-space:normal;"></span></i> (dipole moment). The global reactivity descriptors such as <span style="white-space:normal;"><i></i></span><i>χ<span style="white-space:normal;"></span></i> (electronegativity), <span style="white-space:normal;"><i></i></span><i>χ<span style="white-space:normal;"></span></i> (global hardness), <span style="white-space:normal;"><i></i></span><i>S<span style="white-space:normal;"></span></i> (global softness), and <span style="white-space:normal;"><i></i></span><i>ω<span style="white-space:normal;"></span></i> (electrophilicity index) were derived using Koopman’s theorem and analyzed. The local reactivity parameters, including Fukui functions and dual descriptors were determined and discussed. Experimental and theoretical results were found to be in good agreement. 展开更多
关键词 CEFIXIME Corrosion LANGMUIR Quantum Chemistry Weight Loss
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Phosphorus and Nitrogen Removal by Saturated Vertical-Flow Constructed Wetlands (SVCWs) Type Micro-Pilot Using Shale from Ivory Coast as a Substrate
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作者 Dan Eude Kpannieu Norbert Kouakou Kouadio +4 位作者 N’Dri Séraphin Konan Coulibaly Nagnonta Hippolyte Martine Mallet Lacina Coulibaly Christian Ruby 《Journal of Geoscience and Environment Protection》 2022年第8期24-38,共15页
This study evaluates the performance of shale from Ivory Coast used as substrate in vertical-flow constructed wetlands in removal of phosphates and nitrogen. The pilot-scale artificial wetland has been duplicated: fil... This study evaluates the performance of shale from Ivory Coast used as substrate in vertical-flow constructed wetlands in removal of phosphates and nitrogen. The pilot-scale artificial wetland has been duplicated: filter planted with Panicum maximun and unplanted. They were set up outdoors, and fed with a municipal wastewater. The wetlands have been fed with three batches per week (intermittent) over a period of 3 months. During the operation period, the hydraulic residence time (HRT) 52 h was used, while wastewater temperatures varied from about ~33&#176;C. The removal performance of the constructed wetland units was very good, since it reached on an average 98%, 89.4%, 89.4%, 84%, 80%, 84.8% and 92% for TSS, DOC, BOD<sub>5</sub>, , TKN, TP and respectively. In addition, the vegetation did not demonstrate superior performance to unplanted controls. Therefore, this study focuses on the role of shale in the phosphorus and nitrogen removal from wastewater by constructed wetland. 展开更多
关键词 Constructed Wetlands Vertical Flow SHALE Panicum maximun Phosphorus Removal NITROGEN
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Analysis, Variability and Rainfall Prediction in Sub-Saharan Africa: The Case of the Lake Guiers in Senegal
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作者 Abdou Arame Fall Saidou Ndao Aba Diop 《Open Journal of Ecology》 2023年第11期806-819,共14页
The aim of this article is to predict the rainfall evolution of a sub-Saharan area in which one of the most important freshwater resources is located: Lake Guiers. Characterized by short seasonal rains of three months... The aim of this article is to predict the rainfall evolution of a sub-Saharan area in which one of the most important freshwater resources is located: Lake Guiers. Characterized by short seasonal rains of three months, it experienced a long period of drought in the 1970s. We begin by analyzing the temporal distribution of the rainfall including the variability of the data, with a view to predicting a possible return. For this reason, we present here univariate modeling results of rainfall series collected on three stations in the area. The challenge lies in the adequacy of the parameters for the monthly rainfall series, which generates more or less significant forecast errors on the learning bases because of the missing data. This later motivated their conversion to moving average series. On the other hand, the normality of the latter seems to be rejected by the D’Agostino test. Student’s and Mann-Whitney’s tests confirmed the homogeneity. The autocorlograms show the presence of autoregressive terms in the data. Dickey-Fuller and Mann-Kendall tests reveal both trend and seasonality. The stationarity tests of Dickey-Fuller, Phillips-Perron and KPSS have shown that they are non-stationary. As a result, we did an ARIMA modeling method using the Box-Jenkins [1] method with the R software, which involves estimating model parameters, tests of significance, analysis of residualss, selection according to information criteria and forecasts. The results obtained during the learning-test phase showed a quasi-similarity of the base-tests in all the series except for that of Louga. 展开更多
关键词 Time Series RAIN TREND Stationarity RESIDUALS Model FORECAST
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Factors Predisposing and Triggering the Phenomenon of Shrinkage-Swelling of Clay Soils in the Urban Center of Diamniadio
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作者 Khadim Faye Fatou Samb +1 位作者 Pape Sanou Faye Yves Berthaud 《Geomaterials》 CAS 2023年第2期23-34,共12页
The phenomena of shrinkage and swelling of clay induce damage to housing structures every year. Precipitation, climatic changes and drought are the cause of wall cracks due to subsidence or swelling of the supporting ... The phenomena of shrinkage and swelling of clay induce damage to housing structures every year. Precipitation, climatic changes and drought are the cause of wall cracks due to subsidence or swelling of the supporting soil. This movement alters the balance between the soil and the structures. To explain this defection, the soil is made up of three elements: the solid, the liquid and the gas. Sometimes in a natural way or following a human intervention, one of these elements undergoes an abnormal variation that causes the loss of the balance between land and works. It is in this sense that this article deals on the one hand with the factors of predisposition and triggering of the phenomena of shrinkage-swelling of the clay soils of Diamniadio and on the other hand, the factors of aggravation linked to the lithological heterogeneity and the variation in the thickness of the layers susceptible to shrinkage-swelling. The studies carried out have enabled a deeper understanding of the behavior of expansive soils following their interactions with climate, vegetation, hydrology, hydrogeology, constructions among others, but also the influence of lateral and vertical variations of fine soil facies. 展开更多
关键词 Swelling Clays Expansive Soil Shrinkage-Swelling Desiccation Cracks Diamniadio
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Physical Characterization and Evaluation of the Water Potential of the Watershed of the Ferlo Fossil Valley, Senegal: Louga Area
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作者 Louis Eugène Victor Sambou Saïdou Ndao Papa Babacar Diop Thioune 《Open Journal of Modern Hydrology》 2023年第4期181-192,共12页
This study is an evaluation of the water potential of the Ferlo fossil valley in the Louga area in Senegal. It consisted in determining the volume of water that could be mobilized at the level of a confluence point of... This study is an evaluation of the water potential of the Ferlo fossil valley in the Louga area in Senegal. It consisted in determining the volume of water that could be mobilized at the level of a confluence point of the waters according to the flow lines, where a dam would be placed to create a reservoir. This volume of mobilizable water was compared to the average water consumption of the area in order to evaluate its adequacy or not. To do this, a delineation, physical characterization and mapping of the Ferlo watershed was done using Google Earth, Global Mapper and Arc GIS softwares. A catchment area of 28,754 sq·km was obtained with a perimeter of 976 km, an average slope of 0.52% and a hydraulic length of 336 km. Then the decennial runoff of the watershed was calculated using the CIEH method, this flow is estimated at 1120 cm/s. On the basis of this flow, the annual volume of water that can be mobilized was estimated at 11,089,758 cm per year with a solid deposits of 93 cm per year. The conclusions reached are that there is a lack of mobilizable water resources in the area and that the entire fossil valley needs to be rewatered to provide a sustainable alternative water source. 展开更多
关键词 Ferlo Fossil Valley WATERSHED DAM Water Resources REVITALIZATION
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Impacts of the Sahel-Sahara Interface Reforestation on West African Climate: Intra-Annual Variability and Extreme Temperature Events 被引量:1
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作者 Ibrahima Diba Moctar Camara Arona Diedhiou 《Atmospheric and Climate Sciences》 2019年第1期35-61,共27页
The impacts of the reforestation of the Sahel-Sahara interface on the seasonal distribution of the surface temperature and thermal extremes are studied in the Sahel (West African region lying between 11&#176N and ... The impacts of the reforestation of the Sahel-Sahara interface on the seasonal distribution of the surface temperature and thermal extremes are studied in the Sahel (West African region lying between 11&#176N and 18&#176N). We performed a simulation with the standard version of the RegCM4 model followed by another one using the altered version of the same model taking into account an incorporated forest. The impacts of the vegetation change are assessed by analyzing the difference between the two runs. The reforestation may influence strongly the frequency of warm days (TG90P) and very warm days (TX90P) by decreasing it over the reforested zone from March to May (MAM) and the entire Sahel during the June-August (JJA) period. These TG90P and TX90P indices decrease may be due to the strengthening of the atmospheric moisture content over the whole Sahel region and the weakening of the sensible heat flux over the reforested zone. The analysis also shows a decrease of the TN90P indice (warm nights) over the Sahel during the wet season (JJA) which could be partly associated with the strengthening of the evapotranspiration over the whole Sahel domain. The analysis of additional thermal indices shows an increase of the tropical nights over the entire Sahel from December to February (DJF) and during the warm season (MAM). The strengthening of the tropical night is partly associated with an increase of the surface net downward shortwave flux over the reforested zone. When considering the heat waves, an increase (a decrease) of these events is recorded over the southern Sahel during JJA and SON periods (over the whole Sahelian region during DJF), respectively. Changes in latent heat flux appear to be largely responsible for these extreme temperatures change. This work shows that the vegetation change may impact positively some regions like the reforested area by reducing the occurrence of thermal extremes;while other Sahel regions (eastern part of the central Sahel) could suffer from it because of the strengthening of thermal extremes. 展开更多
关键词 RegCM4 REFORESTATION Heat WAVES SAHEL
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Modified Atomic Orbital Calculations of Energy of the(2s^(2)^(1)S)Ground-State,the(2p^(2)^(1)D);(3d^(2)^(1)G)and(4f^(2)^(1)I)Doubly Excited States of Helium Isoelectronic Sequence from H-to Ca^(18+) 被引量:1
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作者 Malick Sow Ibrahima Sakho +9 位作者 Boubacar Sow Abdou Diouf Youssou Gning Babou Diop Matabara Dieng Abdourahmane Diallo Mamadou DiouldéBa Jean KouhissoréBadiane Mamadi Biaye Ahmadou Wagué 《Journal of Applied Mathematics and Physics》 2020年第1期85-99,共15页
We report in this paper the ground-state energy 2s^(2)^(1)S and total energies of doubly excited states 2p^(2)^(1)D,3d^(2)^(1)D,4f^(2)^(1)I of the Helium isoelectronic sequence from H-to Ca^(18+).Calculations are perf... We report in this paper the ground-state energy 2s^(2)^(1)S and total energies of doubly excited states 2p^(2)^(1)D,3d^(2)^(1)D,4f^(2)^(1)I of the Helium isoelectronic sequence from H-to Ca^(18+).Calculations are performed using the Modified Atomic Orbital Theory(MAOT)in the framework of a variational procedure.The purpose of this study required a mathematical development of the Hamiltonian applied to Slater-type wave function[1]combining with Hylleraas-type wave function[2].The study leads to analytical expressions which are carried out under special MAXIMA computational program.This first proposed MAOT variational procedure,leads to accurate results in good agreement as well as with available other theoretical results than experimental data.In the present work,a new correlated wave function is presented to express analytically the total energies for the 2s21S ground state and each doubly 2p^(2)^(1)D,3d^(2)^(1)D,4f^(2)^(1)I excited states in the He-like systems.The present accurate data may be a useful guideline for future experimental and theoretical studies in the(nI^(2))systems. 展开更多
关键词 Modified Atomic Orbital Theory Variational Calculations Correlated Wavefunction ENERGIES GROUND-STATE Doubly Excited States Helium Isoelectronic Sequence Atoms and Ions
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Efficiency of Nanofiltration Membrane TFC-SR3 and SelRo MPF-34 for Partial Elimination of Fluoride and Salinity from Drinking Water
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作者 Mouhamadou A. Diallo Saidou N. Diop +1 位作者 Mohamad M. Diémé Courfia K. Diawara 《Journal of Water Resource and Protection》 2015年第7期547-552,共6页
Consumption of safe drinking water is essential to human health. The excess of certain elements in drinking water causes health problem for people consuming these waters. In Senegal, the excessive levels of fluoride a... Consumption of safe drinking water is essential to human health. The excess of certain elements in drinking water causes health problem for people consuming these waters. In Senegal, the excessive levels of fluoride and salts found in the groundnut basin cause public health problem such as dental and/or skeletal fluorosis. Thus, the treatment of such waters is essential before consumption to prevent health problems. For a partial removal of fluoride and salinity, we tested the performance of two commercial nanofiltration membranes namely TFC-SR3 and SelRO MPF-34 at laboratory scale. The results showed that TFC-SR3 membrane was very efficient with rejection rates of 83% - 96% for fluoride ions and 89% - 96% for salinity. For SelRo MPF-34 membrane, retention rates of 25% - 52% were obtained for fluoride ions and 24% - 60% for the salinity. 展开更多
关键词 FLUORIDE NANOFILTRATION REJECTION SALINITY
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Renewable Energy Powered Membrane Process for Removal of Excess Fluoride Ions and Safe Drinking Water Supply in Rural Areas in Senegal
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作者 Mohamad Moustapha Dieme Saidou Nourou Diop +3 位作者 Mouhamadou Abdoulaye Diallo Amadou Dieye Amadou Lamine Diouf Courfia Kéba Diawara 《Journal of Environmental Science and Engineering(B)》 2022年第6期241-247,共7页
The analysis results made on drinking water from the rural areas of Kaolack,Diourbel and Fatick central region of Senegal showed the excess of fluoride and chloride ions.Depending on the area,the fluoride concentratio... The analysis results made on drinking water from the rural areas of Kaolack,Diourbel and Fatick central region of Senegal showed the excess of fluoride and chloride ions.Depending on the area,the fluoride concentration in the water can reach 3.5 mg/L.The values obtained are completely above of WHO(World Health Organization)limits.The objective of this study is to assess the performances of membrane filtration units powered by renewable energies for fluoride and salinity excess removal in remote village in Senegal.Many membrane filtration units have been installed in rural areas of regions such as Kaolack,Fatick and Diourbel.These membrane filtration units are equipped by the LPRO(Low Pressure Reverse Osmosis)membranes with 9 m^(2)of surface.A rejection rate of fluoride and chloride ions obtained is 99.33%and 95.25%respectively.The conversion rates are ranged from 45%to 65%.These results clearly show that membrane processes can be used in Africa,especially in isolated rural areas,with the combination of renewable energies.Currently,more than twenty membrane filtration units are installed in Senegal and provide drinking water of very good quality for populations living in rural areas.The prospect is to expand it on a larger scale,which is already underway,with the construction of a desalination plant in Dakar. 展开更多
关键词 FLUORIDE renewable energy LPRO membrane drinking water rural areas
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Optimization of Preparation Conditions of Activated Carbons Based on the Shells of Ricinodendron heudoltii
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作者 Kouakou Yao Urbain Karidioula Daouda +3 位作者 Zran Vanh Eric-Simon Trokourey Albert Yao Kouassi Benjamin Drogui Patrick 《Journal of Materials Science and Chemical Engineering》 CAS 2022年第10期40-58,共19页
The purpose of this work is to prepare better activated carbons from the shells of Ricinodendron Heudelotii by chemical activation with sulfuric acid (H<sub>2</sub>SO<sub>4</sub>) and sodium hy... The purpose of this work is to prepare better activated carbons from the shells of Ricinodendron Heudelotii by chemical activation with sulfuric acid (H<sub>2</sub>SO<sub>4</sub>) and sodium hydroxide (NaOH). The process was optimized by a full factorial design (2<sup>K</sup>) based on the analysis of the external specific surface area of sixteen (16) activated carbons prepared according to the parameters of the preparation. This active analysis reveals that under the preparation conditions, good carbons are obtained for a sodium hydroxide concentration equal to 1 M, an impregnation time of 24 h and carbonization at 500&#730;C for 1 h. The external specific surface of this carbon is 358 m<sup>2</sup><sup> </sup>&#8226;<sup></sup> g<sup>-1</sup>. The characteristics of this prepared carbon are as follows: a pH at zero point charge (pHpzc) of 8.2, a predominantly amorphous structure, a basic character and a low ash content (4.2%). It also has surface functions;the lactonic and carbonyl groups (C=O) at 1600 cm<sup>-1</sup> and the carboxylate groups (O-H or C-O) at 1340 cm<sup>-1</sup>. 展开更多
关键词 Activated Carbons Ricinodendron Heudelotii Chemical Activation OPTIMIZATION Specific Surface
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Improvement of Cashew Apple Juice (<i>Anacardium occidentale</i>L.) by Association with Passion Fruit Juice (<i>Passiflora edulis</i>)
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作者 Marc Adou Yao Désiré Adjouman +2 位作者 Kouadio Olivier Kouadio Achille Fabrice Tetchi N’Guessan Georges Amani 《Food and Nutrition Sciences》 2021年第7期787-804,共18页
Despite many advantages, the many technologies studied to eliminate astringen</span><span style="font-family:Verdana;">cy from cashew apple juice are not all accessible and not adopted by pr</... Despite many advantages, the many technologies studied to eliminate astringen</span><span style="font-family:Verdana;">cy from cashew apple juice are not all accessible and not adopted by pr</span><span style="font-family:Verdana;">ocessors due to the lack of financial means to access these sophisticated technologies. Thus, the formulation of mixed juice based on cashew apple juice and passion fruit juice has proved to be a way of adding value to the cashew apple, a co-product of the production of the nut. After the formulation of the mixed juice in different proportions and the sensory evaluation, it appears that the juice of formulation E is more appreciated by the tasters. Indeed, this juice has preferred sensory characteristics in terms of color (6.90), flavor (5.47), odor (6.42), settling (6.28) and overall acceptance (6.53). These characteristics are similar to those of passion fruit juice in terms of color, odor, and overall acceptance, where the latter obtained scores of 6.94, 7.17 an</span><span style="font-family:Verdana;">d 6.00 respectively;and also, to those of cashew apple juice in terms of f</span><span style="font-family:Verdana;">la</span><span style="font-family:Verdana;">vor and decanting, where the latter obtained scores of 5.19 and 6.14 respe</span><span style="font-family:Verdana;">ctively. Therefore, the addition of passion fruit juice to cashew apple juice results in a new product that is more appreciated when mixed with proportions of 90 mL of passion fruit juice and 10 mL of cashew apple juice. For exam</span><span style="font-family:Verdana;">ple, passion fruit juice, due to its color, flavor, and odor, has helped re</span><span style="font-family:Verdana;">duce the pronounced astringency of raw cashew apple juice. Ultimately, formulation E is recommended to improve the organoleptic value of cashew apple juice. 展开更多
关键词 Cashew Nut Cashew Apple Juice Passion Fruit Juice Sensory Analysis
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