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Energy Positions of the 1,3DeRydberg Series of the He-Like Ions Up to the N= 9 Threshold

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Journal of Applied Mathematics and Physics 2020年第8期8卷 1535-1549页

作者： Matabara Dieng babou diop Malick Sow Youssou Gning Mamadi Biaye Ababacar Sadikhe Ndao Ahmadou Wagué Department of Physics UFR-SATIC University Alioune Diop of Bambey Bambey Senegal Laboratoire Atomes-Lasers Department of Physics University Cheikh Anta Diop Dakar Senegal Department of Physics and Chemistry Faculty of Sciences and Technologies of Formation and Education University Cheikh Anta Diop Dakar Senegal

The doubly excited states of helium-like ions are investigated using a combination of the no-linear parameters of Hylleraas and the β-parameters of screening constant by unit nuclear charge. Calculations are performed for total energies of low-lying doubly excited states (N = 2 - 9) in He-like ions up to Z = 10. The results obtained from the novel method are in good agreement with the available theoretical calculations and experimental observations.

关键词： Electronic Correlations Variational Calculations Atoms And Ions Helium-Like Systems Singlet States Triplet States Matrix Elements Doubly-Excited States Autoionization

Determination of the Series Resistance of a Series Vertical-Junction Silicon (N+/P/P+) Solar Cell under Polychromatic Illumination and Magnetic Field: Effect of Optimum Thickness

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Journal of Modern Physics 2024年第10期15卷 1543-1554页

作者： Dibor Faye babou Dione Mountaga Boiro Pape diop Semiconductor and Solar Energy Laboratory Department of Physics Cheikh Anta Diop University Dakar Senegal

By solving the magneto-transport equation for excess minority charge carriers in the base of the series vertical-junction silicon cell, the phenomenological parameters of the cell can be determined from the boundary conditions. Photocurrent density and photovoltage are determined for each value of applied magnetic field and corresponding optimum thickness, to establish the current-voltage characteristic (Jph(Sf, Sb, z, B, Hop)-Vph(Sf, Sb, z, B, Hop) of the silicon cell under polychromatic illumination. This study will make it possible to reduce the material used (by reducing the optimum thickness), which will help to lower prices. It will also enable us to reduce betting effects (lower series resistance), thereby boosting solar cell efficiency.

关键词： Series Vertical Junction Silicon Cell Static Regime Magnetic Field Optimum Thickness Series Resistance

Variational Calculations of Energies of the (2snl) 1,3Lπand (2pnl) 1,3 LπDoubly Excited States in Two-Electron Systems Applying the Screening Constant per Unit Nuclear Charge

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Journal of Modern Physics 2021年第3期12卷 328-352页

作者： Momar Talla Gning Ibrahima Sakho Maurice Faye Malick Sow babou diop Jean Kouhissoré Badiane Diouldé Ba Abdourahmane Diallo Department of Physics Chemistry UFR Sciences and Technologies University of Thies Thies Senegal Department of Physics Faculty of Sciences and Techniques University Cheikh Anta Diop of Dakar Dakar Senegal Department of Physics UFR Sciences and Technologies University Assane Seck of Ziguinchor Ziguinchor Senegal

In this paper, resonance energies and excitation energies of doubly 2sns 1,3Se, 2snp 1,3P0, 2pnp 1,3De, 2pnd 1,3F0 and 2pnf 1,3Ge excited states of the helium isoelectronic sequence with Z ≤ 10 are calculated. Calculations are carried out in the framework of the variational procedure of the formalism of the Screening Constant per Unit Nuclear Charge (SCUNC). New correlated wave function of Hylleraas type is used. Precise resonance and excitation energies are tabulated and good agreement is obtained when a comparison is made with available literature values.

关键词： Doubly Excited States Helium Isoelectronic Sequence Screening Constant per Unit Nuclear Charge (SCUNC) Correlated Wave Function Resonance Energy Excitation Energies

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

Evaluation of Nutritional Composition of Two Fonio Ecotypes Grown in Casamance (Sénégal)

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Open Journal of Applied Sciences 2024年第2期14卷 533-544页

作者： Amadou Bouye Seydi Amadou diop Animal Physiology Laboratory Department of Animal Biology Faculty of Science and Technology Cheikh Anta Diop University Dakar Senegal Analytical Chemistry and Bromatology Laboratory Faculty of Medicine Pharmacy and Odontology of Dakar Cheikh Anta Diop University Dakar Senegal

In order to better understand the cultural route, biochemical and nutritional composition of two ecotypes of fonio, a study was carried out in village of Tambananing located approximately 7 km from Sédhiou. The objective of studies was to determine nutritional composition of two ecotypes of fonio: the first called momo in short-cycle mandinka (75 - 90 days) and the other called medium-cycle dibong (90 - 110 days). For this, samples of two ecotypes were collected in an experimental field which was split into two equal parts, one sown with the momo ecotype and the other with the dibong ecotype. The nutritional composition (sugars, fats, proteins, minerals, ash, etc.) and the physicochemical properties (pH, humidity, water activity, color, etc.) of fonio’s were determined by appropriate physicochemical methods. The two ecotypes exhibited quite similar physicochemical properties. The levels of biochemical compounds were relatively close with protein contents of 7.05 ± 0.06 mg/100g for the momo ecotype and of 8.02 ± 0.04 mg/100g for the dibong ecotype, in carbohydrates (76.37 ± 1.2 mg/100g for momo and 78.7 ± 1.5 mg/100g for dibong) and in fat (2.92 ± 0.05 mg/100g for momo and 3.14 ± 0.004 mg/100g for dibong). Identical mineral element contents were found except for iron, an element for which the contents were 10.80 ± 0.008 mg/100g for the momo ecotype and 99.59 ± 0.005 mg/100g for the dibong ecotype. Thus, two ecotypes of fonio present a fairly interesting nutritional composition and their consumption deserves to be popularized and could contribute effectively to fight against the problems of malnutrition of certain vulnerable groups.

关键词： Biochemical Composition Ecotypes Fonio Casamance

Restoration or Rehabilitation of the Faleme River Affected by Mining Activities: What Methods?

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Journal of Water Resource and Protection 2024年第4期16卷 233-263页

作者： Mor diop Ibrahima Mall Elhadji Mamadou Sonko Tidiane diop Birane Niane Cheikh Mbow Environmental Sciences Institute (ISE) Cheikh Anta Diop university of Dakar Dakar Senegal Higher School of Mines Geology and Environment Amadou Mahtar Mbow University of Diamniadio (UAM) Dakar Senegal Department of Chemical Cheikh Anta Diop university of Dakar Dakar Senegal Departmentof Engineering Sciences Iba Der Thiam University of Thi&#232s Thi&#232s Senegal

The Faleme River, a West Africa long transboundary stream (625 km) and abundant flow (>1100 million m3) is affected by severe erosion because of mining activities that takes place throughout the riverbed. To preserve this important watercourse and ensure the sustainability of its services, selecting and implementing appropriates restorations techniques is vital. In this context, the purpose of this paper was to present an overview of the actions and techniques that can be implemented for the restoration/rehabilitation of the Faleme. The methodological approach includes field investigation, water sampling, literature review with cases studies and SWOT analysis of the four methods presented: river dredging, constructed wetlands, floating treatment wetlands and chemical precipitation (coagulation and flocculation). The study confirmed the pollution of the river by suspended solids (TSS > 1100 mg/L) and heavy metals such as iron, zinc, aluminium, and arsenic. For the restoration methods, it was illustrated through description of their mode of operation and through some case studies presented, that all the four methods have proven their effectiveness in treating rivers but have differences in their costs, their sustainability (detrimental to living organisms or causing a second pollution) and social acceptance. They also have weaknesses and issues that must be addressed to ensure success of rehabilitation. For the case of the Faleme river, after analysis, floating treatment wetlands are highly recommended for their low cost, good removal efficiency if the vulnerability of the raft and buoyancy to strong waves and flow is under control.

关键词： Faleme River River Restoration Constructed Wetlands Dredging Floating Treatment Wetlands Coagulation-Flocculation

Comparative Study of the Protein Contents of Local and Imported Rice Consumed in Senegal

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Open Journal of Applied Sciences 2024年第2期14卷 561-571页

作者： Amadou Bouye Seydi Nadina Zuleika Leite Serigne Omar Sarr Yérim Mbagnick diop Amadou diop Animal Physiology Laboratory Department of Animal Biology Faculty of Science and Technology Cheikh Anta Diop University Dakar Senegal Analytical Chemistry and Bromatology Laboratory Faculty of Medicine Pharmacy and Odontology Cheikh Anta Diop University Dakar Senegal

Protein is essential for the growth and maintenance of the body. They play a crucial role in different biological processes. This study focuses on comparing the protein contents of local rice grown in the Senegal River valley and rice imported from Asia. The objective is to evaluate the importance of the protein nutritional value of local rice compared to imported rice. Protein contents were determined using the Kjeldahl method. The results of the protein assays show that local rice varieties such as Sahel 108 and Sahel 134 grown in the Thilène basins had protein percentages comparable to those of imported rice. The protein percentages were 15.19% ± 0.91% for the Sahel 108 variety and 16.62% ± 0.01% for the Sahel 134 variety compared to 15.8% ± 0.01% on average for imported rice. Thus from the point of view of protein content, local rice has a nutritional value identical to that of imported rice which it can validly replace. It is important in Senegal to encourage local production, which would make it possible to reduce imports on the one hand and to make quality rice available to the local Senegalese market on the other. Sahel varieties with high protein contents deserve large-scale development to meet the country’s protein needs.

关键词： Proteins Rice Nutritional Value Kjeldahl Method River Valley Senegal

Using Extreme Value Theory Approaches to Estimate High Quantiles for Stroke Data

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Open Journal of Statistics 2024年第1期14卷 150-162页

作者： Justin Ushize Rutikanga Aliou diop Charline Uwilingiyimana African Institute of Mathematical Sciences Rwandan Center Kigali Rwanda College of Agriculture Animal Sciences and Veterinary Medicine (CAVM) University of Rwanda Musanze Rwanda LERSTAD Gaston Berger University Saint Louis Senegal Department of Statistics Applied to Economy INES Ruhengeri Institute of Applied Sciences Musanze Rwanda

This paper aims to explore the application of Extreme Value Theory (EVT) in estimating the conditional extreme quantile for time-to-event outcomes by examining the functional relationship between ambulatory blood pressure trajectories and clinical outcomes in stroke patients. The study utilizes EVT to analyze the functional connection between ambulatory blood pressure trajectories and clinical outcomes in a sample of 297 stroke patients. The 24-hour ambulatory blood pressure measurement curves for every 15 minutes are considered, acknowledging a censored rate of 40%. The findings reveal that the sample mean excess function exhibits a positive gradient above a specific threshold, confirming the heavy-tailed distribution of data in stroke patients with a positive extreme value index. Consequently, the estimated conditional extreme quantile indicates that stroke patients with higher blood pressure measurements face an elevated risk of recurrent stroke occurrence at an early stage. This research contributes to the understanding of the relationship between ambulatory blood pressure and recurrent stroke, providing valuable insights for clinical considerations and potential interventions in stroke management.

关键词： Censored Data Conditional Extreme Quantile Kernel Estimator Weibull Tail Coefficient

Experimental Study of the Anti-Corrosion Performance of Montmorillonite K-10 on Rebar in HCl Environment: Application in Mortar for the Rehabilitation of Reinforced Concrete Degraded by Corrosion

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Open Journal of Civil Engineering 2024年第2期14卷 155-167页

作者： Malang Bodian Mariétou Barro diop-Fall Dame Keinde El-Hadji Dieye Modou Gningue diop Modou Fall Laboratoire de Chimie Physique Organique et dAnalyse Environnementales (LCPOAE) Dpartement de Chimie Univ Cheikh Anta Diop de Dakar Dakar Senegal Laboratoire de Matriaux de Gnie Civil (LMGC) Ecole Suprieure Polytechnique de Dakar Univ Cheikh Anta Diop Dakar Sngal

This work first investigates the corrosion-inhibiting behavior of montmorillonite K-10 on reinforcing steel. The corrosion-inhibiting power of the clay (Montmorillonite) is determined in a medium HCl (C = 1N) using free corrosion potential monitoring, Tafel potentiodynamic polarization curves and electrochemical impedance spectroscopy. The results of this study showed a satisfactory corrosion-inhibiting efficiency of around 72.665% for the optimum content of 1%. This is due to the presence of a stable oxide layer that protects the metal against corrosion. To validate the concept of montmorillonite as a corrosion inhibitor in repair mortar, we now turn to the influence of montmorillonite on the mechanical properties of mortars in the hardened state. In this part, montmorillonite K-10 is added to the mortar by partial substitution of the cement by 5% and 10% of the cement mass. The aim of this study is to ensure that the addition of this clay to the mortar composition will not have a negative effect on its compressive and flexural strengths. The results of the compression and flexural tests showed that the presence of montmorillonite in the mortar improved flexural and compressive strengths for the different compositions studied.

关键词： Clay Reinforced Concrete Corrosion Inhibitor Rehabilitation Electrochemical Methods