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Velocity Form Calculations of Generalized Oscillator Strengths for 3s→ (3p, 4p, 5p, 6p) dipole Transitions of Atomic Sodium in debye Plasma

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Open Journal of Applied Sciences 2024年第6期14卷 1512-1529页

作者： Louis Gomis Clement diatta Moustapha Sadibou Tall Ibrahima gueye Faye Rama Gomis Yande diouf mam.d.u Coulibaly Laboratoire de Physique des Plasmas et de Recherches Interdisciplinaires Departement de Physique Universite Cheikh Anta Diop Dakar Senegal

In this paper, the generalized oscillator strengths (GOSs) of excitations of atomic sodium from ground state to 2p63s0 (3p, 4p, 5p, 6p) states, immersed in debye plasma, were calculated by using wavefunctions which were obtained numerically from the restricted Hartree-Fock (RHF) equation. This RHF equation employs the local density approach for exchange interactions including plasma debye screening. Theoretical RHF and random phase approximation with exchange (RPAE) velocity calculations have shown that the GOSs for excitations to 3 s0(3 p,4 p,5 p,6 p)depend on the plasma debye screening effects, as shown by the reduction in the GOS amplitude with decreasing debye length λd. The agreement between the present RPAE V results for the transitions 3 s→3 s0(3 p,4 p,5 p)and the length calculations of Martínez-Flores was satisfactory. Correlation effects were found quite to be significant in the vicinity of the maxima of the GOS of the 3 s→3 s0(4 p,5 p,6 p)excitations by using the RPAE V approach. We note the poor influence of many electron correlations on the GOS of (3 s→3 p)transition with the same principal quantum number. Finally, we comment that the RPAE V calculations are useful in investigating electron correlation effects on the transition GOS of atomic sodium planted in debye plasma. The present velocity results also reveal that the 3 s→3 s0(5p, 6p)transition GOSs tend to be delocalized due to more significant screening effects at debye lengths λd=20and 30 a.u. for excited subshells 5p and 6p, respectively. We report here novel results of GOS for 3 s→3 s06ptransition obtained from different debye lengths.

关键词： Plasma Screening Effect Correlation Effect Sodium Atomic Velocity Form GOS Restricted Hatree-Fock Random Phase Approximation with Exchange

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Sweetener and Flavor Enhancer Food Additives in Industrial Food Products Marketed in dakar: Frequency and diversity

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Open Journal of Applied Sciences 2024年第1期14卷 101-117页

作者： Alé Kane Alioune Sow Ndèye Adiara Ndiaye Coumba gueye Sagna Papa Amadou diakhaté Mady Cissé Amadou diop Laboratoire des Sciences Biologiques Agronomiques Alimentaires et de Modélisation des Systèmes Complexes (LABAAM) Université Gaston Berger (UGB) Saint-Louis Senegal département des Technologies Agroalimentaires|uFR des Sciences Agronomiques de l’Aquaculture et des Technologies Alimentaires (S2ATA) Saint-Louis Senegal Ecole Supérieure Polytechnique (ESP) Dakar Senegal Laboratoire de chimie analytique et bromatologie UCAD Dakar Senegal

Sweeteners and flavor enhancers are food additives widely used in industry, respectively, to add sweetness and flavor to foods. However, the presence of these substances is often criticized by consumers for their effects on health. What’s more, some scientific studies link these substances to certain pathologies. To guarantee food safety, competent authorities should have food standards based on risk analysis using consistent, reliable data. However, in developing countries, such data is often weak or non-existent. The aim of this study is therefore to carry out a pilot survey to establish the profile of sweeteners and flavour enhancers present in industrial food products marketed in Senegal. The methodology consisted of sampling various food products sold on the Senegalese market, based on analysis of labels containing information on ingredients, including additives. The investigation involved nine stores, one supermarket and 5 mini-markets in dakar. The results showed the presence of 6 taste enhancers in food products, the most frequent being sodium L-monoglutamate (E621), inosinate (E631) and disodium guanylate (E627). Solid broths are the foodstuffs with the highest number of taste exhalters. As for sweeteners, 12 substances were identified, the most frequent being acesulfame potassium (E950), aspartame (E951), sucralose (E955) and saccharin (E954). Given the potential health risks associated with the consumption of these food additives, their control and monitoring on the market should be a priority for the competent authorities.

关键词： Exhalter Sugar Acesulfame Potassium Sodium Monoglutame Artificial Health Risk

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Seasonal Performance of Solar Power Plants in the Sahel Region: A Study in Senegal, West Africa

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Smart Grid and Renewable Energy 2024年第2期15卷 79-97页

作者： Serigne Abdoul Aziz Niang mam.d.u Simina drame Astou Sarr mame diarra Toure Ahmed gueye Seydina Oumar Ndiaye Kharouna Talla FST D&#233partement de Physique Universit&#233 Cheikh Anta Diop de Dakar Dakar S&#233n&#233gal Laboratoire de Physique de l’Atmosphère et de l’Océan Siméon Fongang Université Cheikh Anta Diop Dakar Sénégal

The main objective of this study is to evaluate the seasonal performance of 20 MW solar power plants in Senegal. The analysis revealed notable seasonal variations in the performance of all stations. The most significant yields are recorded in spring, autumn and winter, with values ranging from 5 to 7.51 kWh/kWp/day for the reference yield and 4.02 to 7.58 kWh/kWp/day for the final yield. These fluctuations are associated with intense solar activity during the dry season and clear skies, indicating peak production. Conversely, minimum values are recorded during the rainy season from June to September, with a final yield of 3.86 kWh/kW/day due to dust, clouds and high temperatures. The performance ratio analysis shows seasonal dynamics throughout the year with rates ranging from 77.40% to 95.79%, reinforcing reliability and optimal utilization of installed capacity. The results of the capacity factor vary significantly, with March, April, May, and sometimes October standing out as periods of optimal performance, with 16% for Kahone, 16% for Bokhol, 18% for Malicounda and 23% for Sakal. Total losses from solar power plants show similar seasonal trends standing out for high loss levels from June to July, reaching up to 3.35 kWh/kWp/day in June. However, using solar trackers at Sakal has increased production by up to 25%, demonstrating the operational stability of this innovative technology compared with the plants fixed panel. Finally, comparing these results with international studies confirms the outstanding efficiency of Senegalese solar power plants, other installations around the world.

关键词： Performance Study Photovoltaic Power Plant Season Variations Senegal

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Multi-Elemental Analysis and 2d Image Mapping within Roots, Leaves and Seeds from O. glaberrima Rice Plants using Micro-PIXE Technique

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World Journal of Nuclear Science and Technology 2024年第2期14卷 97-106页

作者： Alassane Traore Anna Ndiaye Christopher Bongani Mtshali Manneh Baboucarr Jean Paul Latyr Faye daouda Mbodj Kandiaba Traore Tapha gueye Ababacar Sadikhe Ndao département de Physique Faculté des Sciences et Techniques Université Cheikh Anta Diop Dakar Senegal département de Chimie Faculté des Sciences et Techniques Université Cheikh Anta Diop Dakar Senegal Tandetron Laboratory IBA Group iThemba LABS Cape Town South Africa Africa Rice Center St. Louis Senegal

understanding metal accumulation at organ level in roots, leaves and seeds in O. glaberrima (OG) is crucial for improving physiological and metabolic aspects in growing Asian and African rice in salted areas. The micro-analytical imaging techniques are required to reveal its accumulation and distribution within plant tissues. PIXE studies have been performed to determine different elements in rice plants. The existing microbeam analytical technique at the iThemba LABS will be applied for the 2d image mapping of fresh rice tissues to perform a concentration of low atomic mass elements (such as Al, Si, P, S, Cl, Ca, Ti, Mn, Fe, Cu, Br, Zn and K) with detection limits of typically 1-10 μg/g. Comparison of the distribution of the elements between leaves, root and seed samples using uptake and distribution of elements in particular environmental conditions with potential amount of salt in water have been performed. We are also expecting to indicate metal exclusion as salt tolerance strategies from leaves, root, and seed compartments using matrix correlation between samples and between elements on rice species.

关键词： PIXE 2d Mapping Rice Concentration Elemental Analysis

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uV/Vis Characterization and Fate of Organic Amendment Fractions in a dune Soil in dakar, Senegal

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Pedosphere 2015年第3期25卷 372-385页

作者： Silwan dAOuK Mohammad HASSOuNA Anne gueye-GIRARdET Seydou NIANG Hans-Rudolf PFEIFER Institute of Earth Sciences Faculty of Geosciences and Environment(FGSE)University of Lausanne Laboratory of Wastewater Treatment Fundamental Institute of North Africa (IFAN)Cheikh Anta Diop University of Dakar

The application of organic amendments on soils poor in organic matter(OM) can improve long-term soil fertility, but may also enhance the mineralization of native soil organic matter. Three organic amendments, compost, sewage sludge and horse manure, used by urban market gardeners in dakar, Senegal were analyzed for their OM maturity. Their fate was evaluated in a 45-d agronomic trial in a sandy Arenosol with lettuce. In each case, water-extractable organic matter(WEOM) and humic-like substances(HLS)were isolated from raw amendments and amended soils, and characterized using ultraviolet-visible(uV/Vis) spectroscopy. Results highlighted the general more aromatic character of HLS and WEOM fractions extracted from compost compared to the other two amendments. When applied to soils, however, these differences were not clearly observed. The aromaticity and humification degree of the labile fraction(WEOM) increased with depth in the first 30 cm for all amendments. This indicated the high lixiviation rates that fresh OM underwent in the studied sandy soil. Finally, a statistical analysis of the results was able to discriminate between surface and deeper horizons and between amended- and non-amended soil samples. Spectroscopic indices showed indeed strong increase/decrease with depth linked with the mineralization/humification processes that the fresh OM from amendments underwent during the 45 d of the agronomic trial. This study highlights the potential of spectroscopic techniques to study agricultural amendment organic matter fractions and their fate in soils.

关键词： absorbance spectroscopy compost fluorescence spectroscopy horse manure humic-like substances sewage sludge,water-extractable organic matter

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The Exact Formulation of the Inverse of the Tridiagonal Matrix for Solving the 1d Poisson Equation with the Finite difference Method

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Journal of Electromagnetic Analysis and Applications 2014年第10期6卷 303-308页

作者： Serigne Bira gueye département de Physique Faculté des Sciences et Techniques Université Cheikh Anta Diop Dakar-Fann Sénégal

A new method for solving the 1d Poisson equation is presented using the finite difference method. This method is based on the exact formulation of the inverse of the tridiagonal matrix associated with the Laplacian. This is the first time that the inverse of this remarkable matrix is determined directly and exactly. Thus, solving 1d Poisson equation becomes very accurate and extremely fast. This method is a very important tool for physics and engineering where the Poisson equation appears very often in the description of certain phenomena.

关键词： 1d Poisson Equation Finite difference Method Tridiagonal Matrix Inversion Thomas Algorithm Gaussian Elimination Potential Problem

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Semi-Analytical Solution of the 1d Helmholtz Equation, Obtained from Inversion of Symmetric Tridiagonal Matrix

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Journal of Electromagnetic Analysis and Applications 2014年第14期6卷 425-438页

作者： Serigne Bira gueye département de Physique Faculté des Sciences et Techniques Université Cheikh Anta Diop Dakar-Fann Sénégal

An interesting semi-analytic solution is given for the Helmholtz equation. This solution is obtained from a rigorous discussion of the regularity and the inversion of the tridiagonal symmetric matrix. Then, applications are given, showing very good accuracy. This work provides also the analytical inverse of the skew-symmetric tridiagonal matrix.

关键词： Helmholtz Equation Tridiagonal Matrix Linear Homogeneous Recurrence Relation

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Exact Inversion of Pentadiagonal Matrix for Semi-Analytic Solution of 2d Poisson Equation

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Journal of Modern Physics 2022年第12期13卷 1525-1529页

作者： Serigne Bira gueye department of Physics Faculty of Sciences and Techniques Cheikh Anta Diop University Dakar-Fann Senegal

This work essentially consists in inverting in an exact, explicit, and original way the pentadiagonal Toeplitz matrix or tridiagonal block matrix resulting from the discretization of the two-dimensional Laplace operator. This method is an algorithm facilitating the resolution of a large number of problems governed by PdEs involving the Laplacian in two dimensions. It guarantees high precision and high efficiency in solving various differential equations.

关键词： Block Matrix Pentadiagonal Matrix 2d Laplacian Toeplitz Matrix Inversion

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New Approach of Geomechanical Properties by Scale Effect and Fractal Analysis in the Kedougou-Kenieba Inlier (Senegal-West Africa)

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Geomaterials 2013年第4期3卷 145-155页

作者： déthié Sarr Meissa Fall Papa Malick Ngom mam.d.u gueye département de Géologie FST-UCAD Université Cheikh Anta Diop de Dakar Dakar Sénégal Institut des Science de la Terre FST-UCAD Université Cheikh Anta Diop de Dakar Dakar Sénégal Laboratoire de Mécanique et Modélisation UFR Sciences de l’ Ingénieur Université de Thiès Thiès Sénégal

This paper shows geometric aspects of rock masses in the Senegalese side of Kédougou-Kéniéba inlier. The studies are done in one part on sedimentary rocks (represented by sandstones) with stratification and on the other part in igneous rocks (represented by basalts). Geometric studies are the fractal configuration and the scale effect. Scale effect is stud- ied by comparing the results of mechanical tests done in the laboratory and on outcrops. For all samples, laboratory pa- rameters are higher than values of field. In this paper, scale effect is characterized by the decrease of mechanical pa- rameters from laboratory samples to field. The scale coefficient is defined and characterizes the relation between me- chanical properties. More importantly, the scale effect is more significant. This scale effect depends largely on the rock anisotropy. The anisotropy depends on the fracturation and the filling. The scale effect takes into account the fracturation, the filling minerals and their diversity which define the complexity of the rock. The anisotropy is complex;the impact of scale effect traduced by an increase of scale coefficient is the highest. Configuration of discontinuities also defines fractal geometry. This fractal aspect appears on the asperities, the spacing and the apertures of discontinuities. The fractal dimension is different from a parameter to another. All these two parameters estimate the stage of fracturation of the rock in a geological system and depend one on another if they are studied in the same element.

关键词： Rock Scale Effect Fractal Kédougou Sedimentary Igneous

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Prevalence and Associated Factors of diabetic Kidney disease in Senegalese Patients: A Cross-Sectional Study in Saint-Louis

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Open Journal of Nephrology 2020年第1期10卷 23-33页

作者： Sidy Mohamed Seck dominique doupa Seraphin Ahou Serigne gueye Macia Engerran Lamine gueye Internal Medicine-Nephrology department Faculty of Health Sciences University Gaston Berger Saint-Louis Senegal uMI 3189 Environnement santé sociétés (CNRS/UCAD/Université de Bamako/CNRST Burkina-Faso) Faculté de Médecine de Pharmacie et d’Odontostomatologie Dakar Senegal Nephrology department Faculty of Health Sciences University of Parakou Parakou Benin Nephrology and Hemodialysis department CH Cahors Cahors France

Introduction: diabetes is a leading cause of chronic kidney disease in the world. during the next decade, its burden is expected to increase in Africa with potential complications such as chronic kidney disease. However, epidemiology and risk factors of diabetic kidney disease are poorly described at population level. This study aimed to determine prevalence of diabetic kidney disease (dKd) in adult diabetics living in Saint-Louis, northern Senegal. Methods: A cross-sectional study including diabetic patients followed-up aged ≥18 years during a five-year period (2013-2018) in Saint-Louis. Clinical and biological parameters were collected during annual community-based mass screening. diabetes was defined as fasting blood glucose ≥ 1.26 g/L confirmed by a second lab dosage. dKd was defined as persistence of albuminuria ≥ 30 mg/24h and/or estimated glomerular filtration rate (eGFR) 2. data were analyzed with Stata 12.0. Results: We included a total of 1310 diabetic patients among whom 3.7% (95% CI = 1.4% - 9.8%) presented dKd. Their mean age was 46.2 ± 11.8 years and sex-ratio was 0.7. Micro-albuminuria and macro-albuminuria were present respectively in 59.2% and 18.4% of patients with dKd and half of them had a normal eGFR. Before the survey 89.8% of patients with dKd were not aware of their renal disease and only four of them had seen a nephrologist. After multivariate analysis, age (OR = 1.5;95% CI = 1.1 - 3.4), duration of diabetes (OR = 1.2;95% CI = 1.6 - 4.4) and hypertension (OR = 2.5;95% CI = 1.4 - 4.6) were associated with the presence of dKd in diabetic patients while no significant association was not found with gender, blood glucose level, smoking and familial history. Conclusion: dKd is a frequent complication in diabetic adult population living in Saint-Louis. Early detection and management should be promoted in order to prevent progression to end-stage renal disease.

关键词： diabetes Kidney disease Epidemiology Saint-Louis

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