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Surface recombination Concept as Applied to Determinate Silicon Solar Cell base Optimum Thickness with Doping Level Effect

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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 ha.et yoro ba Ndeye Thiam Ibrahima Diatta youssou tra.re 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

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 ha.et yoro ba Mohamed Abderrahim Ould El Moujtaba.youssou tra.re 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

β-divergence loss for the kernel density estimation with bias reduced

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Statistical Theory and related Fields 2021年第3期5卷 221-231页

作者： hamza Dhaker El hadji Deme youssou Ciss Mathematiques et statistique Universite de MonctonMonctonCanada UFR SAT Universite Gaston BergerSaint-LouisSenegal

In this paper,we investigate the problem of estimating the probability density *** kernel density estimation with bias reduced is nowadays a standard technique in explorative data analysis,there is still a big dispute on how to assess the quality of the estimate and which choice of bandwidth is *** framework examines the most important bandwidth selection methods for kernel density estimation in the context of with bias *** reference,least squares cross-validation,biased cross-validation andβ-divergence loss methods are described and expressions are *** order to assess the performance of our various bandwidth selectors,numerical simulations and environmental data are carried out.

关键词： bandwidth β-divergence nonparametric estimatio

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+)

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Journal of Applied Mathematics and Physics 2020年第1期8卷 85-99页

作者： Malick Sow Ibrahima Sakho Boubacar Sow Abdou Diouf youssou Gning babou Diop Matabara Dieng Abdourahmane Diallo Mamadou Diouldéba Jean Kouhissorébadiane Mamadi Biaye Ahmadou Wagué Department of Physics Atoms Lasers LaboratoryFaculty of Sciences and TechnologiesUniversity Cheikh Anta DiopDakarSenegal Department of Physics UFR Sciences et TechnologiesUniversity of ThièsThièsSenegal UFR SATIC University Alioune DIOP de BambeyBambeySenegal Department of Physics UFR of Sciences and TechnologiesUniversity Assane Seck of ZiguinchorZiguinchorSenegal Department of Physics and Chemistry Faculty of Sciences and Technologies of Training and EducationUniversity Cheikh Anta DiopDakarSenegal

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 *** 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 *** first proposed MAOT variational procedure,leads to accurate results in good agreement as well as with available other theoretical results than experimental *** 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 *** present accurate data may be a useful guideline for future experimental and theoretical studies in the(nI^(2))systems.

关键词： Modified Atomic Orbital Theory Variational Calculations Correlated Wavefunction Energies Ground-State Doubly Excited States Helium Isoelectronic Sequence Atoms and Ions

Chemotaxonomic Study of the Covid-Organics of Madagascar based on the Chemical Composition of Their Essential Oils

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International Journal of Organic Chemistry 2023年第2期13卷 50-56页

作者： yoro Tine Adama Diédhiou Alioune Diallo Idrissa Ndoye Mamadou baldé Cheikhouna Gaye Benjamin Ndiaye Alassane Wélé Djibril Fall Laboratoire de Chimie Organique et Thé rapeutique Facult&eacute de M&eacutedecine Pharmacie et Odontologie Universit&eacute Cheikh Anta Diop Dakar S&eacuten&eacutegal

The aim of this study was to investigate the chemical composition of the essential oils of “Covid-Organics” of Madagascar (62% Artemisia annua and two other undisclosed medicinal plants) used as curative and preventive treatments of Covid-19, to identify its constituent species. The essential oils isolated by hydro-distillation from two samples (curative and preventive) were analyzed by GC-FID and GC-MS. These essential oils (curative and preventive) were mainly dominated by camphor (17.9% and 11.9%, respectively), spathulenol (4.8% and 11.8%, respectively), α-acorenol (4.3% and 3.7%, respectively), (E)-β-caryophyllene (3.4% and 4.2%, respectively), 1,8-cineole (3.1% and 3.6%, respectively), hexadecanoïc acid (3.8% and 3.2%, respectively) and caryophyllene oxide (3.4% and 2.4%, respectively). From the chemical composition, two species were identified, A. annua characterised by camphor and Cinnamomumcamphora (Ravintsara) characterised by 1,8-cineole and sabinene. However, we were unable to identify the third species.

关键词： Covid-19 Covid-Organics Artemisia annua Essential Oils Chemotaxonomic

Minority Carrier Diffusion Coefficient <i>D</i>*(<i>B,T</i>): Study in Temperature on a Silicon Solar Cell under Magnetic Field

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Energy and Power Engineering 2017年第1期9卷 1-10页

作者： Richard Mane Ibrahima Ly Mamadou Wade Ibrahima Datta Marcel S. Douf youssou tra.re Mor Ndiaye Seni Tamba Grégoire Sissoko Laboratoire des Semi-conducteurs et d’Energie Solaire Facult&eacute des Sciences et Techniques Universit&eacute Cheikh Anta Diop Dakar S&eacute né gal Ecole Polytechnique de Thiè s Thi&egrave s S&eacute né gal

This work deals with minority carrier diffusion coefficient study in silicon solar cell, under both temperature and applied magnetic field. New expressions of diffusion coefficient are pointed out, which gives attention to thermal behavior of minority carrier that is better understood with Umklapp process. This study allowed to determine an optimum temperature which led to maximum diffusion coefficient value while magnetic field remained constant.

关键词： Solar cell Diffusion Coefficient Temperature Magnetic Field

Chemical Variability and Antibacterial Activity of Eucalyptus camaldulensis Essential Oils from Senegal

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International Journal of Organic Chemistry 2022年第4期12卷 173-180页

作者： yoro Tine Alioune Diallo Idrissa Ndoye Cheikhouna Gaye Benjamin Ndiaye Abdoulaye Diop Jean Costa Cheikh Saad Bouh Boye Alassane Wélé Julien Paolini Laboratoire de Chimie Organique et Thérapeutique Faculté de Médecine Pharmacie et Odontologie Université Cheikh Anta Diop Dakar Senegal Université de Corse UMR CNRS 6134 SPE Laboratoire de Chimie des Produits Naturels Campus Grimaldi Corte France Laboratoire de bactériologie-virologie H&ocirc pital Aristide Le Dantec Dakar Senegal

1,8-cineole, also known as eucalyptol, is the main constituent and the most important of the leaf oils of many species of the genus Eucalyptus. In present study, the essential oils isolated by hydrodistillation from the leaves of Eucalyptus camaldulensis from six different locations were analyzed by GC-FID and GC-MS. Essential oil yields ranged from 0.33% to 4.35%. In total, 34 constituents were identified, accounting for 94.0% to 99.8% of the total compositions. 1,8-cineole (46.4% - 84.4%) was the main constituent of all the essential oil samples, except for one sample collected in the Fatick region, which had p-cymene (46.4%) and 1,8-cineole (26.0%) as major compounds. The essential oil showed excellent activity against S. aureus, E. coli and E. faecalis (IZ = 25.3 ± 1.2 mm;18.7 ± 0.6 mm;17.8 ± 0.3 mm, respectively) and moderate activity against P. aeruginosa (IZ = 10.8 ± 0.8 mm). They may have potential applications in food and pharmaceutical products.

关键词： Eucalyptus camaldulensis Essential Oils Antibacterial Activity 1 8-Cineole and GC-SM

The Essential Oil of Ocimum americanum from Senegal and Gambia as a Source of Methyleugenol for the Control of bactrocera dorsalis, Fruit Fly

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Journal of Agricultural Chemistry and Environment 2024年第1期13卷 133-141页

作者： yoro Tine Antonio Alain Coffi Sinzogan Ousmane Ndiaye Cebastiana Sambou Alioune Diallo Ismaila Mbenga Kemo badji El hadji Omar Dieng Assa balayara Jeanne Diatta Cheikhouna Gaye Julien Paolini Jean Costa Alassane Wele Saliou Ngom Laboratoire de Chimie Organique et Thérapeutique Faculté de Médecine Pharmacie et Odontologie Université Cheikh Anta Diop Dakar Sénégal Faculte des Sciences Agronomiques Universite d’Abomey Calavi Cotonou Benin Ecole Nationale Supérieure d’Agriculture (ENSA) Université Iba Der Thiam de Thiès Thiès Sénégal Direction de la Protection des Végétaux Rufisque Sénégal Laboratoire de Chimie des Produits Naturels Université de Corse Corte France National Agricultural research Institute (NARI) Sere Kunda Gambia Institut Sénégalais de recherches Agricoles (ISRA) Dakar Sénégal

The fruit fly, bactrocera dorsalis (Diptera: Tephritidae) is one of the most important pests in all mango-producing areas, particularly in West Africa. In Senegal, O. americanum leaves have been used for several years to control this fly. However, to our knowledge, no chemical studies have been carried out. Thus, the aim of this study is to determine the chemical composition of the essential oil of O. americanum leaves collected in Senegal and Gambia. The essential oil obtained by hydrodistillation of these leaves is analyzed by GC/FID and GC/MS. Yields of essential oils from O. americanum leaves are 3.84% and 2.13%, respectively. Analysis of these essential oils by GC/FID and GC/MS allowed the identification of 23 compounds representing almost 100% of the total compositions. These essential oils are mainly dominated by methyleugenol (72.0% and 75.8%, respectively). Other components in significant percent are trans-β-caryophyllene (13.9% and 13.0%, respectively), germacrene D (4.1% and 3.7%, respectively), β-elemene (3.3% and 0.9%, respectively). Due to the high methyleugenol content, this study explains the attractive potential of O. americanum towards B. dorsalis. In perspective, we plan to evaluate the attractive effect of the essential oil and leaf powder of O. americanum against B. dorsalis, a real pest of mango orchards in Senegal.

关键词： Ocimum americanum Essential Oils Methyleugenol bactrocera dorsalis GC/MS