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World Journal of Condensed Matter Physics 2019年第4期9卷 102-111页

作者： Masse Samba Diop Hamet Yoro Ba Ndeye Thiam Ibrahima Diatta youssou traore Mamadou Lamine Ba El Hadji Sow Oulymata Mballo Grégoire Sissoko Laboratory of Semiconductors and Solar Energy Physics Department Faculty of Science and Technology University Cheikh Anta Diop Dakar Senegal Laboratory of Sciences and Techniques of Water and Environment Polytechnic School of Thiès Thiès Senegal.

New expressions of back surface recombination of excess minority carriers in the base of silicon solar are expressed dependent on both, the thickness and the diffusion coefficient which is in relationship with the doping rate. The optimum thickness thus obtained from the base of the solar cell allows the saving of the amount of material needed in its manufacture without reducing its efficiency.

关键词： Silicon Solar Cell Surface Recombination Velocity Diffusion Coefficient Doping Rate Base Thickness

Irradiation Energy Effect on a Silicon Solar Cell: Maximum Power Point Determination

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Journal of Modern Physics 2018年第12期9卷 2141-2155页

作者： Mamadou Lamine Ba Hawa Ly Diallo Hamet Yoro Ba youssou traore Ibrahima Diatta Marcel Sitor Diouf Mamadou Wade Gregoire Sissoko Laboratory of Sciences and Techniques of Water and Environment Polytechnic School of Thiès Thiès Senegal Laboratory of Semiconductors and Solar Energy Physics Department Faculty of Science and Technology University Cheikh Anta Diop Dakar Senegal

The aim of this study is to determinate the electrical parameters of a white biased silicon solar cell submitted to an irradiation energy of particles (protons, helium, electrons and heavy ions). A theoretical study of the influence of irradiation energy on the photocurrent density, the photovoltage, the maximum power, as well as the maximum efficiency of the solar cell is presented through a resolution of the continuity equation relative to excess minority carrier. Then the expressions of the photocurrent density Jph, the photovoltage Vph, and the excess minority carrier recombination velocity at the back side Sb are established dependent of irradiation parameters ∅p, Kl respectively irradiation flux and intensity. In this work, we propose a method for determining the recombination velocity of the excess minority carrier at the junction Sfmax corresponding to the maximum power point delivered by the photovoltaic generator under the influence of the irradiation. It is then obtained by calculating the derivative of the power with respect to the excess minority carrier recombination velocity Sf at the junction emitter-base. A transcendental equation solution is deduced as eigenvalue, leading to the junction recombination velocity of excess minority carrier and also yields the solar cell maximum conversion efficiency.

关键词： Silicon Solar Cell Irradiation Electrical Parameters Maximum Power Point

Chronic Purulent Otorrhea in the South of the Sahara: Epidemiological, Clinical and Therapeutic Profiles about 135 Cases

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International Journal of Otolaryngology and Head & Neck Surgery 2022年第4期11卷 219-226页

作者： Kassim Diarra N’faly Konaté youssou Sidibé Famagan Bah Boubacary Guindo Siaka Soumaoro Drissa Kaloga Bagayoko Fatogoma Issa Koné Doumbia Kadidiatou Singare Mohamed Amadou Keita Surgery Department University Hospital Gabriel Toure Bamako Mali Surgery Department CHU Mother-Child “Luxembourg” Bamako Mali Department of Anesthesia Resuscitation CHU Mother-Child “Luxembourg” Bamako Mali

Objective: To study the clinical and therapeutic epidemiological profile of chronic purulent otorrhea in the ENT and CCF departments of the Gabriel Touré university hospital. Materials and Method: This was a retrospective study from May 2019 to April 2021. We made an exhaustive sampling of all patients who consulted for chronic purulent otorrhea with a complete medical file. All ages were included (except from 0 to - 5 years), and all sexes combined. The data medium was the patient records and the department’s operating report register. The non-inclusion criteria were patients with incomplete files and patients who were less than 5 years old. Results: In total, we collected 135 cases. The average age of our patients was 29.27 years. The most represented age group was 16 to 25 years old. We noted a male predominance in 60.7%. The associated signs found were hearing loss, earache, tinnitus, ear pruritus, vertigo, headache and facial paralysis. The main pathology involved is chronic otitis media (CMO) in 55.5%, the most serious of which is dangerous chronic otitis (8.1%). All of our patients have received medical treatment. The treatment was surgical in 64% of patients after medical treatment. With the mean follow-up of 6 months, tinnitus and reperforation were the most common complications found in 6.2% and 3.1% respectively. Conclusion: Chronic purulent otorrhea is the most common ear discharge in ENT consultation. The main pathology involved is CMO, the most formidable of which is cholesteatoma. Medico-surgical treatment.

关键词： Chronic Otorrhea Cholesteatoma Myringoplasty Bamako

One-Dimensional Study of Thermal Behavior of Typha Panel: Spectroscopy Characterization of Heat Exchange Coefficient on Front Face

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Journal of Sustainable Bioenergy Systems 2020年第2期10卷 52-61页

作者： Sokhna Khadidiatou Ben Thiam Alassane Ba Mamadou Babacar Ndiaye Issa Diagne youssou traore Seydou Faye Cheikh Thiam Pape Touty traore Ablaye Fame Gregoire Sissoko Ecole Polytechnique de Thiès (EPT) Thiès Senegal University Institute of Technology University of Thiès Thiès Senegal Laboratory of Semiconductors and Solar Energy Physics Department Faculty of Science and Technology University Cheikh Anta Diop Dakar Senegal

Convective heat transfer coefficients, materializing exchanges between solid wall (here typha) and its environment, influence its behavior under excitation pulse. Temperature of wall and its density of flow vary with these coefficients according to its thickness (in depth). This study therefore focuses on the evaluation of convective heat transfer coefficient on front face and the optimal insulation thickness.

关键词： Typha Heat Transfer Coefficients Spectroscopy Optimal Insulation Thickness

Electrical Parameters Determination from Base Thickness Optimization in a Silicon Solar Cell under Influence of the Irradiation Energy Flow of Charged Particles

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Energy and Power Engineering 2020年第1期12卷 1-15页

作者： Ousmane Sow Mamadou Lamine Ba Mohamed Abderrahim Ould El Moujtaba youssou traore El Hadji Sow Cheikh Tidiane Sarr Masse Samba Diop 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

In this work, we study the characteristics I-V and P-V of a silicon solar cell as well as its fill factor, its electrical power from the optimum thickness obtained in the base under variation of the irradiation energy flow of charged particles. The recombination velocity at the junction corresponding to the maximum power point was also deduced.

关键词： Silicon Solar Cell Flow Irradiation Energy Recombination Velocity Optimum Base Thickness

Support Epidemiology and Prognosis of Premature Rupture of Membranes in Pikine National Hospital Center

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Open Journal of Obstetrics and Gynecology 2019年第11期9卷 1519-1526页

作者： Moussa Diallo Abdoul Aziz Diouf Hadja Maimouna Barro Daff Natty Seck Aminata Niass youssou Toure Khalifa Fall Codou Sene Seck Alassane Diouf Departement of Obstetrics and Gynecology Pikine University Hospital Thiaroye Pikine Sénégal Cheikh Anta Diop University of Dakar Gynecological and Obsetric Clinic Public Institution Aristide-Le Dantec Health Center Dakar Senegal

Premature rupture of membranes (PROM) complicates 3% of preterm pregnancies and occurs in 60% to 80% of term pregnancies. However, its management remains largely controversial. The objective of this study was to establish the epidemiological profile, to study the management and the prognosis of Premature rupture of membranes (PROM) in our practice. Patients and methods: It was a prospective, descriptive and analytical study from May 1st 2016 to January 31st 2017 at the Pikine National Hospital Center. The target population consisted of all patients received at the hospital with premature rupture of membranes and who had given birth in the structure. The variables studied were: marital status, mode and reason for admission;risk factors;antecedents;prenatal care;the clinical and paraclinical examinations;support and immediate maternal and fetal neonatal complications. Results and comments: The mean maternal age was 27.34 years and the majority of women were aged between 18 and 39 years (94.4%). Fifty-one point three percent of patients were primiparous, large multiparous represented only 2.5%. The majority of patients (385 patients or 66.9%) had consulted in the first 12 hours following the onset of fluid flow. For 20.1% of them this flow was associated with uterine contractions. Hidden risk factors were dominated by the twin pregnancy. The blood count showed that 38.8% of patients had leukocytosis and CRP was positive in 18.3% of patients. An ampicillin-based antibiotics was established in 42.6% of cases, corticosteroid therapy in 5.2% and 1% in tocolysis. An expectation was adopted in 65.7% of cases, induction of labor in 7.3% and a cesarean section immediately in 27% of cases. In total, 65.7% of patients had vaginal delivery and 34.3% cesarean. The perinatal mortality rate was 3.6% or 22 newborns on 610. Two cases of endometritis were observed and one case of immediate postpartum hemorrhage. No maternal deaths were recorded. Conclusion: These results show that the

关键词： Premature Rupture of Membranes Childbirth Stillbirth Chorioamnionitis

Influence of Temperature and Frequency on Minority Carrier Diffusion Coefficient in a Silicon Solar Cell under Magnetic Field

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Energy and Power Engineering 2019年第10期11卷 355-361页

作者： Seydina Diouf Mor Ndiaye Ndeye Thiam youssou traore Mamadou Lamine Ba Ibrahima Diatta Marcel Sitor Diouf Oulimata Mballo Amary Thiam Ibrahima Ly Grégoire Sissoko Laboratory of Semiconductors and Solar Energy Physics Department Faculty of Science and Technology University Cheikh Anta Diop Dakar Senegal Electromechanical Department Polytechnic School of Thiès Thiès Senegal.

In this study, the effects of temperature and frequency on minority carrier diffusion coefficient in silicon solar cell under a magnetic field are presented. Using two methods (analytic and graphical), the optimum temperature corresponding to maximum diffusion coefficient is determined versus cyclotronic frequency and magnetic field.

关键词： Solar Cell Diffusion Coefficient Temperature Magnetic Field Frequency

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

Sociodemographic Factors Associated with Delays in Breast Cancer

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Open Journal of Obstetrics and Gynecology 2017年第4期7卷 455-463页

作者： Mamour Gueye Serigne Modou Kane Gueye Moussa Diallo Ousmane Thiam Aissatou Mbodji Aliou Diouf Khalifa Fall youssou Toure Hadja Maimouna Barro Daff Jean Charles Moreau Gynaecologic and Obstetric Clinic Aristide Le Dantec Teaching Hospital Dakar Senegal

Objectives: The aim of our study was to investigate the relation of some sociodemographic factors and delays presentation in breast cancer. Patients and method: This was an observational study in Breast Unit of Aristide Le Dantec Teaching Hospital in Dakar. Were included in the study all patients followed for breast cancer from January 2008 to December 2014. The following variables were selected and stratified: age, place of living, educational attainment, menopausal status, socioeconomic status and family history of breast cancer. For each variable, an association with the stage and presentation delay was assessed. Results: Two hundred and fifty nine (259) patients met the inclusion criteria. No correlation was found between the studied socio-demographic factors and delay. Negative history of family breast cancer was associated with presentation delay. The only factor associated with locally advanced breast cancer after adjusting confounding factors was low level of income. Conclusion: A significant percentage of women with breast cancer in Senegal are experiencing presentation delay. Coordinated efforts with public health department are needed to educate the focused groups and mitigate the barriers.

关键词： Breast Cancer Presentation Delay Stage Survival

Lamella Silicon Solar Cell under Both Temperature and Magnetic Field: Width Optimum Determination

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Journal of Electromagnetic Analysis and Applications 2020年第4期12卷 43-55页

作者： Dibor Faye Sega Gueye Mor Ndiaye Mamadou Lamine Ba Ibrahima Diatta youssou traore Masse Samba Diop Gora Diop Amadou Diao Gregoire Sissoko Laboratory of Semiconductors and Solar Energy Physics Department Faculty of Science and Technology University Cheikh Anta Diop Dakar Senegal

This work deals with determining the optimum thickness of the lamella wafer of silicon solar cell. The (p) base region makes up the bulk of the thickness of the wafer. This thickness has always been a factor limiting the performance of the solar cell, as it produces the maximum amount of electrical charges, contributing to the photocurrent. Determining the thickness of the wafer cannot be only mechanical. It takes into account the internal physical mechanisms of generation-diffusion-recombination of excess minority carriers. They are also influenced by external factors such as temperature and magnetic field. Under these conditions, magneto transport equation is required to be applied on excess minority carrier in lamella base silicon solar cell. It yields maximum diffusion coefficient which result on Lorentz law and Umklapp process. Then from photocurrent, back surface recombination velocity expressions are derived, both maximum diffusion coefficient and thickness dependent. The plot of the back surface recombination calibration curves as function of lamella width, leads to its maximum values, trough intercept points. Lamella optimum width is then obtained, both temperature and magnetic field dependent and expressed in relationships to show the required base thickness in the elaboration process.

关键词： Silicon Vertical Junction Back Surface Recombination Velocity Magnetic Field Temperature Lamella Width