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Study and Optimization of a Photovoltaic Mill System Functioning on the Course of the Sun

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Energy and Power Engineering 2017年第4期9卷 260-272页

作者： Tafsir Abdoulaye Gaye Biram Dieng Senghane Mbodji ousmane Sow Grégoire Sissoko Department of Physics UFR Applied Sciences and Information and Communication Technologies Alioune Diop University of Bambey Bambey Senegal Universitary Institute of Technology University of Thies Thies Senegal Department of Physics Faculty of Science and Technology Cheikh Anta Diop University of Dakar Dakar Senegal

This paper dealt with the optimization of the performance of a photovoltaic mill system operating on the sun race. Depending on the characteristics of the powered load which is a DC motor driving a grain mill and on the weather conditions (temperature and illumination), we noted a very big difference between the potential maximum power and that actually transferred to the load. In order to improve the overall efficiency of the system, we use an adaptation circuit consisting of a boost converter controlled by a numerical MPPT (Maximum Power Point Tracking) command. With the Perturb & Observe (P & O) algorithm, the MPPT control measure the photocurrent, the photo tension and the power released by the photovoltaic generator. From this result, the MPPT control adjusts the duty cyclic of the converter to bring the system to the optimum operating point. Hence, using MATLAB/Simulink software, we did the modeling and the simulation of the system which is composed by a PV generator, a boost converter, a Pulse Width Modulation and a DC motor.

关键词： PV Generator Boost Converter PWM Signal MPPT Control Perturbation & Observation DC Motor Mill

Process for the Biological Removal of Fe (II) from Reconstituted Waters on a Support of Filter Material with Coated Jujube Seeds

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Journal of Geoscience and Environment Protection 2022年第12期10卷 65-76页

作者： Mamadou Faye Falilou Mbacké Sambe Alpha ousmane Toure Mouhamed Ndoye Codou Guèye Mar Diop Water Energy Environment and Industrial Processes Laboratory Ecole Supérieure Polytechnique (ESP) Dakar Senegal Cheikh Anta Diop University Dakar Senegal

Three beakers for removing Fe (II) in reconstituted water (doped with FeSO4) were built and tested. Given the set operating conditions ([O2] > 4 mg·L-1, Patm = 1.013 bar, T = 25°C ± 1°C and [Fe2+]0 = 0.5 to 2 mg·L-1), removal of iron was caused by biological and possibly physical and chemical oxidation because there is a quantity of free oxygen in the medium. The extent of each type of oxidation has not been evaluated as it specifically studies the biological degradation of iron in these beaker tests by setting the operating conditions (pH > 6.5, dissolved oxygen from 0 to 8 mg·L-1, Redox Potential from 100 to 400 mV). The experimental studies focused particularly on the measurements of maximum wavelength, conversion efficiencies from Fe (II) to Fe (III), the effect of the Fe (II) concentration, the influence of pH, the action of the temperature of the prepared solutions and the effect of O2 concentration under specified operating conditions. It noticed precipitated amounts of iron deposited at the bottom of the beakers. Thus, the low concentrations of Fe (II) detected in the influent after the biological oxidation operation could be attributed to microorganisms that consume iron as a substrate.

关键词： Biofilm Batch Test Biological Oxidation Iron Removal Beaker Doped Water

Multi-Criteria Analysis Using Remote Sensing and GIS: Insight into Groundwater Potential of the Fissured Aquifers in the Liptako Socle (Southwestern Niger)

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Journal of Water Resource and Protection 2021年第11期13卷 881-899页

作者： Maman Sani Abdou Babaye Karimou Dia Hantchi Ibrahim Wagani Boukari Issoufou ousmane Issoufou Sandao Department of Geology UMR SERMUG Faculty of Science and Techniques Dan Dicko Dankoulodo University Maradi Niger Department of Geology Faculty of Science and Techniques Abdou Moumouni University Niamey Niger

In the basement of southwestern Niger, weathering and fractured zones concentrate most of the groundwater. This study focuses on fractured media and aims to identify areas of productivity in this aquifer to improve the region’s water coverage. The cartographic approach developed made it possible to establish synthetic maps based on multi-criteria analysis. The hydrogeological parameters selected include fracturing data, drainage system, slope and piezometric level as well as shallow and deep lithology. The choice of these criteria is based on their physical meaning but also on the availability of data. The integration of all the criteria in a GIS allowed to generate maps of recharge and potential productivity of fractured aquifers in the area. The validation of these thematic maps with independent data confirms their utility as reference standards for accessibility for future resource exploitation. Like any spatialization tool, potential recharge maps will provide valuable information about areas where infiltration is more important, and help control and manage risk zoning. The upward evacuation effect is even more prominent along the lineaments, faults or fractures: thus, to avoid possible pollution and to locate the future hydraulic structures, the analysis of the potential recharge zones remains necessary. The potential productivity index map, in addition to the very punctual sites identified by the fracturing study, made it possible to define areas of high potential productivity.

关键词： Multi-Criteria Analysis Fissured Aquifers Productivity Groundwater Potential Niger

Analysis of the Level of Pollutants in the ICS Location Area

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Open Journal of Air Pollution 2023年第3期12卷 92-101页

作者： Sokhna Die Ka Dia Issa Samb ousmane Niass Thaddée Adiouma Seck Gorgui Ka Natural Justice Hub de Dakar Senegal Organic and Therapeutic Chemistry Research Team (ECOT) Department of Chemistry University Alioune Diop Bambey Senegal

The present study deals with the analysis of the level of pollution found in the area where the Chemical Industries of Senegal (ICS) is located. The results of various field surveys and physicochemical analyses show a high exposure of sulphur and phosphate. This study aims to define abatement strategies to reduce the effects of pollution in the area where ICS is located and mitigate the harmful impacts to the health of the population by creating a system to inform the population of the level of concentration of pollutants in the environment. This will allow the different targets to understand pollution, its manifestations and its effects on health and the environment, prevention, participation in the limitation of pollutant emissions and the formation of eco-citizens sensitive to the issue of environmental pollution of ICS.

关键词： Environment Pollutants Physicochemical Analysis

Experimental Processus for Acquisition Automatic Features of I-V Properties and Temperature of the Solar Panel by Changing the Operating Point

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Circuits and Systems 2016年第11期7卷 3984-4000页

作者： Babou Dione ousmane Sow Mamadou Wade L. Y. Ibrahima Senghane Mbodji Gregoire Sissoko Laboratory of Semiconductors and Solar Energy Physics Department Faculty of Science and Technology University Cheikh Anta Diop Dakar Senegal University Institute of Technology University of Thiès Thiès Sénégal Polytechnic School of Thiès Thiès Sénégal Université Alioune DIOP de Bambey Bambey Sénégal

A development of an acquisition of the characteristic of a solar panel by automatic load variation system is put into play and coupled to an instrumentation chain for taking account of temperature. A programmed digital microprocessor control enables this automation. Design and implementation of a device for automation of variations of the resistive load are powered by solar panel. It is provided by a PIC 16F877A running a computer program that we have developed on the basis of an algorithm according to the operation that we have set. By varying automatically the resistive load, we were able to automatically acquire the characteristic I-V and temperature of the solar panel. With automatic combinations of the 10 resistors, we have obtained 1024 measures of the characteristic curve of the solar cell which has a good accuracy. The change in load and temperature measurement allows us to have the characteristic curves parameterized by temperature.

关键词： Microcontroller Solar Panel Temperature I-V PIC 16F877A

Comparative Study of Thermal Comfort Induced from Masonry Made of Stabilized Compressed Earth Block vs Conventional Cementitious Material

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Journal of Minerals and Materials Characterization and Engineering 2019年第6期7卷 385-403页

作者： Hassane Seini Moussa Philbert Nshimiyimana Césaire Hema ousmane Zoungrana Adamah Messan Luc Courard Institut International d’Ingénierie de l’Eau et de l’Environnement (2iE) Laboratoire Eco-Matériaux et Habitats Durables (LEMHaD) Rue de la Science Ouagadougou Burkina Faso Université de Liège (ULiège) Urban and Environmental Engineering (UEE) Liège Belgium Université Catholique de Louvain (UCLouvain) Architecture et Climat Louvain-La-Neuve Belgium Université de Liège (ULiège) Service socio-anthropologie du développement Liège Belgium

This paper investigates the stabilization effect on compressed earth blocks (CEB) produced from quartz-kaolinite rich earthen material stabilized with 0% - 25% calcium carbide residue (CCR). The paper evaluated various physico-thermal properties of the stabilized CEB and thermal comfort in the model building made of CEB masonry. The optical properties of CEB were evaluated from the mineral composition of the earthen material and CCR and apparent density of the CEB. A simulation was carried out on naturally ventilated model building whose masonry is made of CCR stabilized CEB comparing to the so-called conventional cementitious materials such as cement blocks and concrete. The results showed a decrease of the apparent density of the CEB from 2100 kg·m–3 for unstabilized CEB (0% CCR) to 1600 kg·m–3 for 25% CCR stabilized CEB. The thermal conductivity and depth of penetration of the heat flux on a 24 hours period of CEB respectively decreased from 1 W·m–1·K–1 and 12.7 cm for 0% CCR-CEB to 0.5 W·m–1·K–1 and 10.2 cm for 25% CCR-CEB. The emissivity, solar absorptivity and visible absorptivity of the CEB respectively decreased from 0.82, 0.82 and 0.82 for 0% CCR-CEB to 0.80, 0.64 and 0.64 for 25% CCR-CEB. The number of hours of warm and humid thermal discomfort was impacted for stabilized CEB based masonry in comparison with cement based masonry. The warm discomfort in building made of 20% CCR-CEB masonry was 400 hours lesser than that in building made of hollow cement blocks masonry. If air conditioning system is used to keep the indoor temperature below 28°C, the economy of 310,000 CFA francs (535 USD) is made every year on energy consumption for cooling in the model building made of 20% CCR-CEB masonry, corresponding to 9.6% less, with respect to that made of hollow cement blocks masonry.

关键词： Calcium Carbide Residue Compressed Earth Block Cementitious Materials Energy Plus Software Thermal Comfort

Contribution of Imaging in the Diagnosis and Management of Type 1 Autoimmune Pancreatitis Associated with Main Bile Duct Cholangitis: A Case Report

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Case Reports in Clinical Medicine 2022年第5期11卷 175-181页

作者： Keita Aboubacar Sidiki Camara Mamoudou Diallo Mamadou Dembele Adama Bah ousmane Aminata Cisse Mamadou Medical Imaging Department H&ocirc pital Nord Franche Comté Trévenans France Faculty of Health Sciences and Techniques the Gamal Abdel Nasser University of Conakry Conakry Guinea Medical Imaging Department Centre Hospitalier Intercommunal Elbeuf Louviers Elbeuf France Medical Imaging Department Centre Hospitalier de Blois Blois France

Introduction: Autoimmune pancreatitis type 1 (AIP) is a rare condition characterized by inflammatory and fibrosing involvement of the pancreas, associated with elevated serum IgG4 and potential involvement of other organs. It often mimics a malignant tumor with which the differential diagnosis is often difficult. Observation: We report a case of AIP type 1, in a 70-year-old patient, with a heavy history of arterial hypertension, insulin-induced type II diabetes, overweight, gastric ulcer, ischemic heart disease with triple bypass, COPD, revealed by intense abdominal pain and acute evolution. The diagnosis was evoked on imaging, in front of an aspect of “sausage pancreas”, with delayed contrast enhancement of the pancreas, loss of lobulations, and the presence of a fibrous peripancreatic shell. The biological and histological assessment confirmed the diagnosis and avoided inappropriate surgical treatment. Conclusion: AIP type 1 is a rare pathology whose diagnosis is difficult. Only a perfectly interpreted imagery can evoke it. The biological assessment, in particular, the elevation of the serum level of IgG4 and the histology make it possible to confirm the diagnosis. The challenge in its management is to avoid unnecessary surgery and/or inappropriate treatments. Imaging, in this context, plays a preponderant role, in particular, thanks to the dynamic injection sequences of gadolinium chelates on MRI which suggest the fibro-inflammatory nature of pancreatic lesions.

关键词： Autoimmune Pancreatitis CT MRI

Growth, Development and Suitability for Kent of Mango Rootstocks on Soil Substrates Collected under Anacardium occidentaleL., Khaya senegalensis(Desv.) A. Juss and Mangifera indicaL., in Casamance, Senegal

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American Journal of Plant Sciences 2021年第12期12卷 1800-1816页

作者： Omar Boun Atab Diedhiou ousmane Ndiaye Boubacar Camara Antoine Sambou Saliou Ndiaye Cheikh Tidiane Ba Assane Seck University Ziguinchor Senegal National Higher School of Agriculture University Iba Der Thiam Thies Senegal Cheikh Anta Diop University Dakar Senegal

With an overall contribution of nearly 4 billion CFA francs to Senegal’s income, providing 23,000 employments more than 50% are women in 2021, the mango sector has shown its importance in the Senegalese economy even if the potential remains largely under-exploited. Thus, the study on the main local varieties remains an important perspective. This work carried out in the farm of the agroforestry department concerns the growth and development of four varieties (Pince, Kouloubadaseky, Sierra Leone and Diourou) on different soils (Mangifera indica, Anacardium occidentale and Khaya senegalensis). This work aims to contribute to the knowledge of the most cultivated varieties in Casamance. It is also a question of seeing the response of these varieties to grafting with the Kent variety. An experiment was conducted for one year with a split plot design consisting of 4 replicates (blocks). Each block contains 4 plots and each plot contains 3 sub-plots with 20 plants each. The parameters measured were: diameter at the collar, height, number of leaves, biomass, number of growth units and grafting success rate. The Sierra Leone variety showed the best growth results in terms of diameter at the crown (0.511 ± 0.090), leaf production (16 ± 2.52) and dry biomass (28.67 ± 16.80). The Kouloubadaseky variety had the best height record (41.90 ± 6.15) and the Diourou variety gave the best results in terms of fresh biomass (68.94 ± 30.90), number of growth units (9.350 ± 2.06) and grafting success rate (78.84% ± 29.44%). Anacardium occidentale soil substrate gave the best growth in height (39.73 ± 5.54 cm) while the substrate collected under M. indica L produced a greater number of leaves (13.14 ± 3.64) and grafting success rate (71.12% ± 37.25%). The Khaya senegalensis substrate recorded the highest values in biomass prod

关键词： Mango Substrate Biomass Grafting Growth Unit Kent

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乙烯环氧化填充床反应器反应性能模拟研究

乙烯环氧化填充床反应器反应性能模拟研究

作者：奥斯曼（Issoulon Assoumane Majga ousmane）北京化工大学

学位级别：硕士

A comprehensive two-dimensional （2D） reactor model has been developed to simulate the reaction performance in a packed bed reactor for producing ethylene oxide. An exponent-function kinetic model has been incorporated to a commercial computational fluid dynamics （CFD） code FLUENT by user defined functions for the reaction performance modeling for ethylene expoxidation. The approach and model have been validated with the actual data collected from research papers where the same kinetic model is adopted. Various graphs indicating the variation of pressure, temperature and velocity along the packed bed reactor are given. Temperature, inlet ethylene and oxygen concentrations are important factors for ethylene oxide selectivity. It is demonstrated that regulating the concentrations of ethylene and oxygen, leads to high selectivity of ethylene oxide. When the ethylene concentration is maintained at 25.6%, it was noticed an increase in ethylene oxide selectivity with increasing concentration of oxygen. At high ethylene concentrations between 10 and 25.6%, higher selectivity to ethylene oxide is obtained. The temperature has a significant function in increasing ethylene oxide selectivity in the packed bed reactor;high reaction temperature up to 503 K promotes high selectivity to ethylene oxide as well as higher conversion of ethylene and oxygen. The optimal temperature is between:463-503 K. The mole fractions of ethylene oxide and carbon dioxide increases with the increase in reaction temperature. At 503 K the concentrations of oxygen, methane and ethylene decreases while the concentrations of ethylene oxide, water and carbon dioxide increased. To summarize, the simulation results show that the ethylene oxide selectivity and the concentrations of oxygen and ethylene are closely related to each other and are obviously influenced by operating conditions studied in this work.

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