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Journal of Modern Physics 2020年第11期11卷 1891-1910页

作者： momar talla gning Ibrahima Sakho Malick Sow Department of Experimental Sciences UFR Sciences and Technologies University of Thies Thies Senegal Atoms Laser Laboratory Department of Physics Faculty of Sciences and Technologies University Cheikh Anta Diop Dakar Senegal

In this work, the total energies of doubly excited states (ns2) 1Se, (np2) 1De, (nd2) 1Ge, (nf2) 1Ie, (ng2) 1Ke, and (nh2) 1Me of the helium isoelectronic sequence with Z ≤ 10 are calculated in the framework of the variational method of the Screening Constant by Unit Nuclear Charge (SCUNC). These calculations are performed using a new wavefunction correlated to Hylleraas-type. The possibility of using the SCUNC method in the investigation of high-lying Doubly Excited States(DES) in two-electron systems is demonstrated in the present work in the case of the (nl2) 1Lπ doubly excited states, where accurate total energies are tabulated up to n = 20. All the results obtained in this paper are in agreement with the values of the available literature and may be useful for future experimental and theoretical studies on the doubly excited (nl2) 1Lπ states of two-electron systems.

关键词： Doubly Excited States Helium-Like Systems Screening Constant by Unit Nuclear Charge (SCUNC) Wave Functions Correlated Total Energy

Photoionization Study of Cl II, Ar II and Kr II Ions Using the Modified Atomic Orbital Theory

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Journal of Modern Physics 2018年第14期9卷 2594-2622页

作者： Abdourahmane Diallo Mamadou Diouldé Ba Jean Kouhissoré Badiane momar talla gning Malick Sow Ibrahima Sakho Department of Physics UFR Sciences and Technologies University Assane Seck of Ziguinchor Ziguinchor Senegal Department of Physics Faculty of Sciences and Techniques University Cheikh Anta Diop of Dakar Dakar Senegal

Resonance energies of the Cl II-[3s23p3(2D5/2)]nd and [3s23p3(2P3/2)]nd, Ar II-3s23p4(1D2)ns, nd and of the Kr II [4s24p4(1D2)]ns, nd and 4s24p4(3P2,3P1)]ns, 4s24p4(3D2)]ns, nd and 4s24p4(3D2, 1S0)]ns, nd Rydberg series are reported. Natural widths of the Ar II-[3s23p4(1D2)]ns, nd series are also reported. Calculations are done in the framework of the Modified Atomic Orbital Theory (MAOT). Excellent agreements are obtained with available theoretical and experimental data. High lying accurate resonance energies up to n = 40 are tabulated. The possibility to use the MAOT formalism report rapidly with an excellent accuracy the position of the excitation resonances as well as their width within simple analytical formulae is demonstrated.

关键词： Resonance Energies Rydberg Series Natural Widths Modified Atomic Orbital Theory (MAOT)

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

Production and Characterization of Biodiesel from Rapeseed Oil through Optimization of Transesterification Reaction Conditions

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Journal of Energy and Power Engineering 2019年第10期13卷 380-392页

作者： momar talla Dieng Takumi Iwanaga Yokoyama Christie Yurie Shuichi Torii Department of Advance Mechanical System Engineering Kumamoto UniversityKurokami2-39-1Kumamoto 860-8555Japan Laboratoire de Photonique Quantique d’Energie et de NanoFabrication Facultédes Sciences et TechniquesUniversitéCheikh Anta Diop de Dakar(UCAD)Dakar-Fann DakarB.P.5005Sénégal

In this study,biodiesel fuel was produced from rapeseed oil via transesterification *** optimum reaction conditions were determined by varying alcohol type and its concentration considering their influence on the yield and properties of produced *** and ethanol were alcohol used in the transesterification *** density of biodiesel was measured at 15℃according to EN ISO 12185 test method and its viscosity was determined at 40℃by using a Brookfield digital viscometer(DV-II+Pro).Shimadzu Auto-Calculating Bomb calorimeter CA-4AJ was used to measure the high heating *** optimum transesterification conditions found were alcohol:oil ratio of 18:1,1%of potassium hydroxide as catalyst,60 min of reaction time,60℃of reaction temperature and stirring speed of 650 *** properties under these conditions satisfied the regulatory standards and are slightly similar to those of mineral diesel tested in same *** methanol gives better results compared to ethanol.

关键词： Biodiesel transesterification reaction optimization process rapeseed oil.

A New Method for the Determination of Cyanide Ions and Their Quantification in Some Senegalese Cassava Varieties

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American Journal of Analytical Chemistry 2014年第3期5卷 181-187页

作者： Younoussa Diallo momar talla Gueye Cheikh Ndiaye Mama Sakho Amadou Kane Jean Paul Barthelemy Georges Lognay Département Génie Chimique et Biologie Appliquée Ecole Supérieure Polytechnique Université Cheikh Anta Diop de Dakar Dakar Sénégal Institut de Technologie Alimentaire Route des Pères Maristes Dakar Sénégal Unité Analyses Qualité Risques et Laboratoire de Chimie Analytique Gembloux Agro-Bio Tech Université de Liège Gembloux Belgique

Cassava (Manihot esculenta Crantz) is a starchy staple food that previous researches have showed to contain cyanogenic compounds, precursors of hydrocyanic acid, undoubtedly toxic for humans. With the aim to determine food security in cassava, this study developed a simple, fast and less expensive step for quantifying cyanide ions by using micro-diffusion with modified Conway cells. After an enzymatic degradation, the cyanide ions were quantified by electrochemical procedures. The validation of this method is estimated. The concentration of cyanide ions at different part of the samples was determined. The results showed high toxicity in some fresh Senegalese consumed cassava varieties (>100 mg HCN·kg﹣1). However, in the processed cassava products, less than 10 mg HCN·kg﹣1 was found in the different varieties studied except for the chips where the levels of CN﹣ contents were important (>49 mg HCN·kg﹣1).

关键词： Cassava Cyanogenic Glycosides Cyanide Ion Micro-Diffusion Toxicity

Development of a Performant Method for Glucocapparin Determination in Boscia senegalensis Lam Ex. Poir.: A Study of the Variability

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American Journal of Analytical Chemistry 2013年第2期4卷 104-110页

作者： momar talla Gueye Dogo Seck Abdoulaye Diallo Danny Trisman Christophe Fischer Jean-Paul Barthelemy Jean-Paul Wathelet Georges Lognay Gembloux Agro-Bio Tech Unit Analysis Quality Risks—Laboratory of Analytical Chemistry University of Liege Gembloux Belgium Institute of Food Technology (ITA) Hann-Dakar Senegal Regional Centre for Research in Ecotoxicology and Environmental Safety (CERES/Locustox) Dakar Senegal University of Liege Gembloux Agro-Bio Tech Unit of General and Organic Chemistry Gembloux Belgique

This study describes a glucocapparin determination method. Based on rapeseed determination of glucosinolate (GSL), the equation of the average straight regression line is Y = 100.42X – 0.03 (R2 = 0.9998). Enzymatic hydrolysis of glucocapparin extracted from leaves and fruits of B. senegalensis, analyzed by SPME-GC-MS confirmed the presence of methylisothiocyanate as the main hydrolysis glucocapparin product. Monitoring glucocapparin contents in B. senegalensis leaves and fruits collected in 4 localities in Senegal showed differences between organs according localities and periods of harvest. Glucocapparin content was very high in dry season particularly in January and the lowest rates were recorded during the rainy period between August and November.

关键词： Boscia Senegalensis Validation Method Glucocapparin Monitoring Senegal

Chemical Characterization and Insecticidal Activity of Ethyl Acetate and Dichloromethane Extracts of Drypetes gossweileri against Sitophilus zeamais, Tribolium castaneum and Rhyzopertha dominica

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Journal of Life Sciences 2013年第10期7卷 1030-1040页

作者： Aba Toumnou Lucie Seck Dogo Lakouetene Didier Ponel Beranger Bolevane Ouantinam Serge Florent Gueye momar talla Traore Anna Namkosserena Salomon Noba Kandioura Sembene Mbacke Syssa-Magale Jean-Laurent Regional Centre for Studies on the Improvement of Plant Adaptation to Drought Thies 3320 Senegal Regional Centre for Ecotoxicology Studies and Chemical Environment Security (CERES-Locustox) Dakar 3300 Senegal Department of Natural sciences University of Bangui Bangui 908 Central Africa Republic Institut of Food Technology Dakar 2765 Senegal Regional Pole of Applied Research to Development Farming Systems in Central Africa (PtL4SAC) N 'Djamena 764 Chad Department of Plant Biology Cheikh Anta Diop University Dakar 5005 Senegal Department of Animal Biology Cheikh Anta Diop University Dakar 5005 Senegal

The use of botanical pesticides in pest management during storage against insects is often encouraged because synthetic insecticides produce undesired effects. Bark powder ofDrypetes gossweileri is used by farmers in pest management in Central Africa Republic. Hexane, dichloromethane, ethyl acetate and methanol were used for extraction bark powder by maceration. Insecticidal activity of the extracts was tested on Sitophilus zeamais, Tribolium castaneum and Rhy_-opertha dominica. The mortality rate, the number of surviving insects and the number of emerged insects were measured variables. Calculated mortality was obtained by applying Aboth＇s formula. The variables are submitted to variance analysis, model with four factors （plants, insects, doses and time） in Minitab 14. The results of analysis showed that the mortality rate has a very highly significant variation following extracts, doses, insects and time considered （P 〈 0.001）. Extracts with ethyl acetate and dichloromethane of D. gossweileri are effective against S. zeamais and R. dominica at high doses （1, 0.5, 0.250 g/10 mL of solvent）. These effective extracts were characterized by gas chromatography coupled with mass spectrometry. Molecules such as l-isothiocyanatomethyl, thiocyanic acid, phenylmethyl ester and other were characterizated. These results may consolidate traditional use olD. gossweileri in pest management.

关键词： Control stored grains pests' management Drypetes gossweileri.

Pest Management of Storage Pests Using Extracts of Afrostyrax lepidophyllus against Sitophilus zeama＇（s, Tribolium castaneum and Rhyzopertha dominica

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Journal of Agricultural Science and Technology(B) 2014年第1期4卷 58-66页

作者： Aba Toumnou Lucie Gueye momar talla Bolevane Ouatinam Serge Florent Traore Anna Gueye Sabelle Lakouetene Didier Ponel Beranger Namkosserena Salomon Ndoye Ousmane Syssa-Magale Jean-Lauren Noba Kandioura Sembene Mbacke Seck Dogo Faculty of Sciences University of Bangui Bangui Central Africa Republic lnstitut of Food Technology Dakar 3300 Senegal Regional Centre for Ecotoxicology Studies and Chemical Environment Security (CERES-Locustox) Dakar 3300 Senegal Regional Pole of Applied Research to Development Farming Systems in Central Africa (PRASAC) Bangui Central Africa Republic West and Central African Council for Agricultural Research and Development Dakar 18523 Senegal Faculty of Sciences Cheikh Anta Diop University Dakar 5005 Senegal

The use of botanical pesticides in pest management during storage against insects is often encouraged because synthetic insecticides produce multiple side-effects on human health and environment. Insecticidal activity of the hexane, dichloromethane, ethyl acetate and methanol extracts of bark ofAfrostyrax lepidophyllus was tested on Sitophilus zeama~：~, Tribolium castaneum and Rhy-opertha dominica. The mortality rate was measured variable. The results of analysis showed that the mortality rate has a very highly significant variation following extracts, doses, insects and time considered （P 〈 0.001）. Extracts with ethyl acetate and hexane of A. lepidophyllus are effective against S. zeamais at the highest doses （1 g/10 mL and 0.5 g/10 mL of solvent）. These effective extracts werc characterized by gas chromatography coupled with mass spectrometry. Molecules such as thiocyanic acid, ethyl ester： dimetbylditbiophosphinic acid and other were characterizated. These results may consolidate traditional use ofA. lepidophylh^s in pest management.

关键词： Control stored grains pests management Afrostyrax lepidophyllus.

Evaluation of Performance and Emission Characteristics of Biodiesel Fuel Produced from Rapeseed Oil

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Journal of Energy and Power Engineering 2020年第3期14卷 75-84页

作者： momar talla Dieng Takumi Iwanaga Yokoyama Christie Yurie Shuichi Torii Department of Advance Mechanical System Engineering Kumamoto UniversityKurokami2-39-1Kumamoto 860-8555Japan Laboratoire de Photonique Quantique d’Energie et de Nano Fabrication Facultédes Sciences et TechniquesUniversitéCheikh Anta Diop de Dakar(UCAD)Dakar-Fann DakarB.P.5005Sénégal

The objective of the present study is to examine and compare the performance and emission characteristic of two biodiesel fuels produced from rapeseed oil via transesterification *** biodiesel fuels(ROME(Rapeseed Oil Methyl Ester)and ROEE(Rapeseed Oil Ethyl Ester))were selected based on their properties obtained from an optimization of transesterification conditions.A Yanmar diesel engine has led to evaluating their performance parameters such as fuel consumption rate,exhaust gas temperature and emission characteristic corresponding to nitrogen oxides(NOx),carbone monoxide(CO)and carbon dioxide(CO2).A comparative analysis was carried out using normal diesel fuel tested in same experimental *** consumption rate was measured by observing the volumetric rate from the fuel tank of the engine supported by *** exhaust gas temperature and emission characteristic were measured simultaneously by using a testo 350 flue gas *** to the results,biodiesel fuels showed a higher fuel consumption rate and exhaust gas temperature under an increase of engine *** also exhibited lower NOx emission with a slight rise in CO and CO2 emission compared to mineral diesel *** exhibited low emission gas compared to ROEE and mineral *** can be evaluated as a promising alternative fuel for diesel engine.

关键词： Biodiesel transesterification reaction rapeseed oil diesel engine emission characteristics