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Energy and Power Engineering 2020年第7期12卷 445-458页

作者： Meimouna Mint Sidi Dede Mamadou Lamine ba Mamour Amadou ba Mor Ndiaye Sega Gueye el Hadj Sow Ibrahima Diatta Masse Samba Diop Mamadou Wade Gregoire Sissoko Laboratory of Semiconductors and Solar Energy Physics Department Faculty of Science and Technology University Cheikh Anta Diop Dakar Senegal Ecole Polytechnique de Thiès (EPT) Thiès Senegal

The monochromatic absorption coefficient of silicon, inducing the light penetration depth into the base of the solar cell, is used to determine the optimum thickness necessary for the production of a large photocurrent. The absorption-generation-diffusion and recombination (bulk and surface) phenomena are taken into account in the excess minority carrier continuity equation. The solution of this equation gives the photocurrent according to absorption and electronic parameters. Then from the obtained short circuit photocurrent expression, excess minority carrier back surface recombination velocity is determined, function of the monochromatic absorption coefficient at a given wavelength. This latter plotted versus base thickness yields the optimum thickness of an n+-p-p+ solar cell, for each wavelength, which is in the range close to the energy band gap of the silicon material. This study provides a tool for improvement solar cell manufacture processes, through the mathematical relationship obtained from the thickness limit according to the absorption coefficient that allows base width optimization.

关键词： Silicon Solar Cell Absorption Coefficient back Surface Recombination Optimum Thickness

Shunt Resistance Determination in a Silicon Solar Cell: Effect of Flow Irradiation Energy and base Thickness

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Journal of electromagnetic Analysis and Applications 2019年第12期11卷 203-216页

作者： Ousmane Sow Mamadou Lamine ba Hamet Yoro ba Mohamed Abderrahim Ould el Moujtaba Youssou Traore Masse Samba Diop Habiboullah Lemrabott Mamadou Wade Grégoire Sissoko University Institute of Technology University of Thiès Thiès Sénégal Laboratory of Semiconductors and Solar Energy Physics Department Faculty of Science and Technology University Cheikh Anta Diop Dakar Senegal Ecole Polytechnique de Thiès Thiès Sénégal

The concept of the recombination of the minority carrier’s recombination velocity at the junction and in the rear, is used for determination, optimum thickness and then shunt resistance in the base of the silicon solar cell, maintained in steady state and under energy from the irradiation flow of charged particles. Resistance shunt is obtained and modeled through a relationship expressed according to the flow and energy of irradiation imposed on the solar cell.

关键词： Silicon Solar Cell Irradiation Recombination Velocity Shunt Resistance Optimum base Thickness

Intracellular behaviour of samarium and europium in lactating mammary gland

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Journal of Rare Earths 2012年第3期30卷 274-277页

作者： Ayadi Ahlem Maghraoui Samira el Hili Ali Galle Pierre Tekaya Leila Laboratoire de physiologie Faculté de Médecine de Tunis. 15 rue Djebel lakhdhar. 1007 La Rabta. Tunis. Université Tunis El Manar Tunisie Laboratoire de microscopie électronique Faculté des Sciences de Tunis Campus universitaire 2092 El Manar II Tunis Université Tunis El Manar Tunisie. Université Tunis El Manar Tunisie Universidade Estdual de Santa Cruz CNPq rod. Ilheus-Itabuna Km. 16 Ilheus Ba. Brasil

The subcellular localization of samarium and europium, two rare-earths, increasingly used in both medical and industrial fields, has been studied in several organs such as liver and kidney but never in the mammary gland despite of its importance in the biology of lactation and nutrition domains. The intracellular behaviour of samarium and europium after their intra-peritoneal administration in the lactating mammary gland cells was investigated. The results showed the presence of very electron dense deposits in the glandular epithelial cell lysosomes. These particular lysosomes were never observed in the mammary cell lysosomes of control rats. These intralysosomal deposits were probably composed of insoluble samarium or europium phosphates by analogy with previous studies, the transmission electron microscopy, the ion mass microscopy and the electron probe microanalysis, and other techniques allowing the identification of the chemical structure of the intralysosomal deposits.

关键词： samarium europium transmission electron microscopy (TEM) lysosome mammary gland lactation rare earths

Assessment of radioactivity levels in some oil samples from the western desert,Egypt

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Nuclear Science and Techniques 2007年第2期18卷 118-122页

作者： A. ABbaDY A.M. el-ARABI W. RASHED Physics Department Faculty of Science South Valley University Qena Egypt

Distributions of natural gamma-emitting radionuclides were determined in 93 oil samples collected from some petroleum fields in the western desert of Egypt. The radioisotope activities in the area under investigation lay in the range of (21 ± 4) to (38 ± 13) Bq?L-1 for 226Ra, (9 ± 2) to (15 ± 5) Bq?L-1 for 232Th, and (154 ± 28) to (303 ± 54) Bq?L-1 for 40K. The mean values were 27, 12, and 201 Bq?L-1, respectively. Among oils, variations in radionuclide ac- tivities could be on account of differences in TDS, HCO3, and ba, with high or low pH. In this environment, oil prop- erties differently affected the mobilization of natural radionuclides. The range of 226Ra variation had been compared with available data from other countries. The calculated absorbed dose rate ranged from 22.33 to 32.66 nGy?h-1 in lo- cation (B) and (E) respectively, which was less than the accepted value.

关键词：埃及西部沙漠地区油料样品放射性评估

Effect of Pb Ions on the Ionic Conductivity of Some Silicate Glass Systems

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Journal of Materials Science & Technology 2002年第5期18卷 391-394页

作者： A.G.Mostafa Z.A.el-Hadi 等 PhysicsDepartment FacultyofScienceAl-AzharUniversityNasrCityCairoEgypt ChemistryDepartment UniversityCollegeforGirlsAinShamsUniversityCairoEgypt

Conductivity of glasses in the systems ***, (where R=Ca, Sr or ba) was investigated between room temperature and 530 K. The dependence of log resistivity as well as the activation energy on the PbO content has been studied. based on the present experimental results, the possible different conduction mechanisms in such glasses are discussed. It was postulated that Pb2+ ions may represent the major charge carrying species in these glasses. This assumption was confirmed by the calculations of the mean distance between the interstitial Pb2+ ions and the effective center of the O2- ions in the glass networks. The variation in the values of the density and the molar volume with PbO content is also discussed in view of the obtained activation energies for the studied glass-systems.

关键词： Ionic conductivity Pb ion Silicate glass systems

Solar Photocatalysis of a Pesticide in a Tubular Reactor on Titaniferous Sand as a New Semi-Conductor

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Processes for the Clarification of the Crude Oil of baobab Seeds Extracted by Pressing on Activated Carbon elaborated from the Capsules of the Fruit (Adansonia digitata L.)

Advances in Chemical Engineering and Science（化学工程与科学期刊） 2023年第2期

作者： el hadji Moussa Diop Kalidou ba Mamadou Faye Alpha Ousmane Toure Falilou Mbacké Sambe

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Advances in Chemical Engineering and Science 2023年第2期13卷 105-118页

作者： Edouard Mbarick Ndiaye Alioune Sow Kalidou ba Mouhamed Ndoye Yousra el Idrissi Seyni Ndiaye Hamza el Moudden Papa Guedel Faye Hicham Harhar Nicolas Ayessou Mohamed Tabyaoui Mady Cisse Laboratory of Water Energy Environment and Industrial Processes (LE3PI) ESP-UCAD ESP-UCAD Cheikh Anta Diop University Dakar Senegal Laboratory of Materials Nanotechnology and Environment Faculty of Sciences-Rabat Mohammed V University of Rabat Rabat Morocco Laboratory of Biological Agronomic Food Sciences and Modeling of Complex Systems (LABAAM) UFR of Agronomic Scienc-es Aquaculture and Food Technologies (S2ATA) Gaston Berger University of Saint-Louis Saint-Louis Senegal Higher School of Technology of el Kelaa of The Sraghna Cadi Ayyad University Marrakech Morocco

The baobab, Adansonia digitata L. plays an important role in the economy of local populations. The oil from the seeds of the baobab fruit is nowadays highly prized because of its numerous cosmetic and therapeutic applications and its composition of unsaturated fatty acids, sterols and tocopherols. However, unlike refined oils, locally extracted baobab oil has not undergone purification operations to ensure its quality. Only a filtration on special cloths is carried out after decantation. Indeed, the oil obtained after pressing is cloudy because of the presence of various impurities. It therefore requires treatment operations to make it more attractive and of higher quality. Therefore, in order to provide innovative solutions to local companies to improve the quality of vegetable oils, a study of clarification (treatment) of crude oil is necessary. An experimental device has been developed in the laboratory. It includes a glass column and a filter bed of dune sand and activated carbon. This study has shown the efficiency of the experimental device. Indeed, the activated carbon, thanks to its adsorbing power, has allowed a significant decrease in turbidity at the 5% threshold, from 14.61 NTU for the raw oil to 0.08 NTU for the oil filtered on 3% carbon and 0.033 NTU for the oil filtered on 5% carbon. That is to say an abatement higher than 95%. This decrease in turbidity could be correlated with the decrease in brown index from 187.39a for the initial crude oil to 128.53d for the oil treated with 3% activated carbon versus 187.59a for the oil filtered on cloths. The lowest brown index was observed with the filtration using 5% activated carbon (35.99b). Thus, for the yellowness index, only the filtration on 5% charcoal allowed to obtain a significant decrease in yellowness. The yellowing index of the oil with 5% was 44.67b against 79.04a for the oil filtered with 3% activated carbon, 86.33a fo

关键词： Activated Carbon baobab Oil Clarification Filtration Process

Pulmonary Hypertension in Chronic Hemodialysis Patients at Aristide Le Dantec University Hospital

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Open Journal of Nephrology 2022年第1期12卷 93-100页

作者： Maria Faye Ahmed Tall Lemrabott Niakhaleen Keita Moustapha Faye Romina Ghassani Mansour Mbengue bacary ba Seynabou Diagne Abdou Niang el Hadj Fary Ka Nephrology Department Aristide Le Dantec University Hospital Dakar Senegal Cheikh Anta Diop University Dakar Senegal Nephrology Department Dalal Jamm Hospital Dakar Senegal

Introduction: Pulmonary hypertension (PH) is defined as high blood pressure in the lungs. It is recently described as a vascular disease entity in chronic kidney disease, particularly for chronic hemodialysis patients. The aims of this study were to determine the prevalence of PH, to describe clinico-biological and morphological characteristics and to identify risk factors associated with PH in hemodialysis patients. Patients and methods: This is a cross-sectional, descriptive, and analytical study during a period of 8 months from January 1, 2019, to August 31, 2019, in the hemodialysis center of nephrology department of Aristide Le Dantec Hospital. All chronic hemodialysis patients for more than 3 months and with PH confirmed by cardiac doppler ultrasound were included. Results: During the study period, 25/94 patients on chronic hemodialysis, presented with pulmonary hypertension (26.6%). The mean age was 49.3 ± 12.9 years. The sex ratio (M/F) was 0.92. Exertional dyspnea was found in 18 patients (72%). Cardiac auscultation revealed an arrhythmia in 3 patients (12%), augmented second heart sound in 12 patients (48%). On transthoracic doppler ultrasound, pulmonary systolic arterial pressure was on average 51.4 ± 13.2 mmHg. PH was moderate in 13 patients (52%), mild in 9 patients (36%) and severe in 3 patients (12%). The left ventricular ejection fraction was altered in 9 patients (36%). Three patients (12%) had valve calcifications. They were mainly located at aortic valve (8%) and mitral valve (4%). The major risk factors associated to PH in our patients are pathological fractures (p = 0.023), aortic calcifications (p = 0.023), ischemic heart disease (p = 0.023). The duration of hemodialysis represents another favoring factor (p = 0.042). Also implicated are arrhythmias (p = 0.004), high cardiac index (p = 0.043), ventricular dilatation (p = 0.034) and left atrial dilation (p = 0.015), as well as dilation of the inferior vena cava (p = 0.048).

关键词： Pulmonary Hypertension Chronic Hemodialysis Patients Transthoracic Doppler Ultrasound Dakar

Conformational Radiotherapy of Prostatic Adenocarcinoma at the Dalal Jamm Hospital,Senegal

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Perpetrators of Sexual Violence against Minors in Casamance (Senegal)

Journal of Cancer Therapy（癌症治疗） 2020年第10期

作者： Mouhamadou bachir ba Amadou Ibra Diallo Fatimatou Néné Sarr el hadji Aliou baldé Ibrahima Thiam Papa Macoumba Gaye

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