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Advances in Microbiology 2022年第4期12卷 177-191页

作者： Mariama Ciré Kourouma Malick Mbengue Ndèye Coumba Daga sarr khady sarr Coumba Touré Kane Laboratory of Applied Microbiology and Industrial Engineering (MAGI) Ecole Supérieure Polytechnique (ESP) Université Cheikh Anta Diop Dakar-Fann Senegal Université Sine Saloum El Hadj Ibrahima Niass (USSEIN) Kaolack Senegal

Vinegar production is seriously affected by the sensitivity of acetic acid bacteria (AAB) to high temperature, high ethanol concentrations, and high acetic acid concentrations. The aim of this study was to investigate the thermo-ethanol-acid tolerance characters of five AAB strains (VMA1, VMA5, VMA7, VMAM, VMAO) previously isolated from fermented mango alcohol and belonging to Gluconoacetobacter genera. As result, the five AAB strains exhibited good growth and acid production at temperatures up to 45°C;they could tolerate and produce acetic acid at ethanol concentrations up to 20% (v/v). In addition, the studied strains showed growth at acetic acid concentrations up to 4.5% (w/v). Strains VMA7 and VMAO showed the highest resistance properties: they demonstrated acid production at 50°C and VMAO could even grow at 60°C;they tolerated and produced acetic acid at 25% (v/v) ethanol concentration;they showed resistance to acetic acid concentrations up to 6% (w/v). Considering all these properties, the use of these strains would seriously contribute to improving the quality of the vinegar produced and help to reduce the cooling water feeds in vinegar production especially in hot countries in the context of global warming.

关键词： Vinegar Acetic Acid Bacteria Thermotolerant Ethanol-Tolerant Acid-Tolerant

Numerical Simulation of Two-Dimensional Natural Convection in a Confined Environment with the Vorticity-Stream Function Formulation

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Open Journal of Fluid Dynamics 2018年第1期8卷 44-58页

作者： Mame khady Kane Cheikh Mbow Mamadou Lamine Sow Joseph sarr Department of Physics Cheikh Anta Diop University of Dakar Dakar Senegal

A numerical study is presented on the problem of 2D natural convection in a differentially heated cavity. The equations governing this unsteady flow phenomenon were solved using the vorticity-stream function formulation of the Navier-Stokes equations and heat. The results obtained are compared with the results of the literature and make it possible to validate this approach. In this work, we studied the heat transfer in a cavity and we determined the variation of the local Nusselt number which allows obtaining the rate of thermal transfer by convection in an enclosure. We analyzed thermal fields for different Rayleigh numbers by selecting two points to visualize temperature fluctuations over time. Thus, the creation of the ascending and descending movements of the fluid inside the cavity was analyzed. We have also established temperature histograms for the graphical presentation of the temperature distribution. The modeling of the two-dimensional problem was established using a “Fortran 90” calculation code. The results also show the different vorticity contour maps in laminar flow regime. We have presented our results of numerical simulations using a visualization tool. The Rayleigh number varies in the range of 103 to 106 for a Prandtl number equal to 0.72 corresponding to air.

关键词： Numerical Study Differentially Heated Cavity Vorticity Modeling

A Study on Natural Convection of Air in a Square Cavity with Partially Thermally Active Side Walls

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Open Journal of Fluid Dynamics 2017年第4期7卷 623-641页

作者： Mame khady Kane Cheikh Mbow Mamadou Lamine Sow Joseph sarr Department of Physics Cheikh Anta Diop University of Dakar Dakar Senegal

In this present work, we study heat transfer in a confined environment. We have to determine the thermal and dynamics fields of the cavity while observing the effect of the Rayleigh number which depends on the characteristics of the fluid and the temperatures imposed. The behavior of boundary layers in natural convection is analyzed along this square cavity. The central halves of its vertical walls are heated at different temperatures. The left active part is at a higher temperature than the one on the right wall. The remaining inactive parts and the horizontal walls (upper and lower) are adiabatic. The thermal and dynamic modeling of two-dimensional problem was done using a calculation code Fortran 90 and a visualization software ParaView based on the finite volume method. The equations governing this phenomenon of unsteady flow have thus been solved. This allows the modeling of both air flow and heat transfer with a numerical stabilization of the solution. So, we have presented our results of numerical simulations using a visualization tool. The results show the different velocity and temperature curves, velocity vectors and isotherms in laminar flow regime.

关键词： Heat Transfer Natural Convection Square Cavity Laminar Flow Regime

Lithostratigraphic and Geochemical Characterization of Tobene Phosphate Deposits: A Case Study of Tobene South 1

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International Journal of Geosciences 2023年第2期14卷 251-269页

作者： Ndeye khady Ndiaye Mouhamadoul Bachir Diouf Pan African University for Life and Earth Science Institute University of Ibadan Ibadan Nigeria Département de Géologie Faculté des Sciences et Techniques Université Cheikh Anta Diop Dakar Senegal

Tobene is the third exploitation panel of the Taiba Phosphate deposits. It is divided into five sectors and its exploitation started in 2003 after the closure of the Ndomor and Keur Mor Fall panels. The Taiba phosphate deposit has been the object of several studies based on lithology, biostratigraphy, geochemistry, and petrography;however, few investigations on the variation in thickness of the phosphate layer within the Tobène sector have been conducted. This study seeks to analyze the lithostratigraphic and geochemical characteristics of the phosphate layer in the Tobène South1. Results from the lithostratigraphic study show from top to bottom the following succession: the sandy overburden, the sandstone formation, the Silico-feralitic formation, the variegated roof clays, the Taiba formation (homogeneous ore and heterogeneous ore), and the foliated attapulgite of the wall. Geochemical analysis reveals an unequal distribution of major oxides (P2O5, CaO, Fe2O3, Al2O3, and SiO2). The area is dominated by P2O5 concentrations between 20% and 32%, the K parameter (=CaO/P2O5) has an average of 1.36. The iron associated with aluminum (feral) is present in the southern part and on the contours of the sector;the dominant silica concentration is 20%. Correlations established between the major oxides show a strong relationship with p-values 0.05, nevertheless there is proportionality in the evolutions between the chemical variables CaO and P2O5, on the other hand, an opposite evolution between P2O5 and the two chemical parameters silica (SiO2) and feral.

关键词： Tobene Taiba Keur Mor Fall Ndomor Sandy Recovery Silico-feralitic

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在华马里留学生汉语学习的现状调查研究

在华马里留学生汉语学习的现状调查研究

作者： khady TOURE（卡蒂）吉林大学

学位级别：硕士

汉语是非常有魅力的语言,中国地大物博历史悠久,文化物产相当的丰富。非常多的马里留学生被中国的文化吸引前往中国来学习汉语。马里共和国和中国建交于1960年,长久以来两国一直有着非常良好的交流。随着市场经济和文化贸易的发展,国家... 详细信息

汉语是非常有魅力的语言,中国地大物博历史悠久,文化物产相当的丰富。非常多的马里留学生被中国的文化吸引前往中国来学习汉语。马里共和国和中国建交于1960年,长久以来两国一直有着非常良好的交流。随着市场经济和文化贸易的发展,国家之间的交流越来越频繁,从而促生了汉语的学习的氛围。很多马里的留学生学习汉语一方面是为了可以得到有关汉语的工作,还有一部分原因是对中国的文化产生兴趣。为了两国之间的发展,越来越多的马里留学生来到中国,来学习汉语,探寻中国文化的魅力。第一章,主要介绍了马里的文化背景,马里汉语教育的现状以及作者在中国学习汉语的感受。第二章,以马里学生的角度出发,对汉语本身进行分析,主要包括语法,书写,语音方面。第三章,讨论马里学生学习汉语之学习者个体因素,总结了汉语的学习环境、方式以及留学生的宗教信仰对马里留学生学习汉语的具体影响。第四章,分析马里学生汉语学习的社会因素,提出了两国的文化差异,不同的思维方式以及社会认同对学习汉语产生的重要作用。最后本文将对马里留学生学习汉语提出具体建议。本文系统研究了马里留学生学习汉语的现状及产生原因,对以后非汉语圈的马里留学生来华学习汉语有重要的引导和建议作用。

关键词：马里留学生汉语文化个体原因影响学习因素

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在中国经商的文化挑战

在中国经商的文化挑战

作者： Ndeye khady Ndiaye 北京交通大学

学位级别：硕士

随着全球化经济的不断深化,中国已经成为最具吸引力的外商投资市场之一。中国与西方国家经济合作越来越密切,在相互交往中,跨文化交际成为一个重要的问题。可以看到,跨国公司经营中很多失败的案例都源于对于文化差异的忽视。世界经济的... 详细信息

随着全球化经济的不断深化,中国已经成为最具吸引力的外商投资市场之一。中国与西方国家经济合作越来越密切,在相互交往中,跨文化交际成为一个重要的问题。可以看到,跨国公司经营中很多失败的案例都源于对于文化差异的忽视。世界经济的一体化一方面为全球各个国家提供了相互合作的巨大机会,但另一方面这种一体化也会在不同文化相互合作中产生一些影响相互交往的独特的问题。中国市场在世界经济中具有重要的作用,许多跨国公司纷纷来到中国寻找商业机会拓展其在华的业务。这些跨国公司很多是通过合资或者收购的方式进入中国市场的。因此,研究在中国的跨文化交际是一个重要的课题。本论文运用吉尔特·霍夫斯塔和迈克尔·邦德(Hofstede and Bond)的文化维度理论,阐述对中国与其它国家一般文化差异的理解。本文从五个方面讨论了文化差异对管理实践的影响:合作战略、冲突管理、决策、团队特征和激励系统。论文分为三个部分。第一部分是引言,介绍了论文的研究背景、研究问题和研究方法。第二部分介绍了在中国经商的文化挑战,为文章的主体部分,分为五节。第一节对中国的自然状况、历史概况、政治体制、经济文化概况作了简要介绍,第二节从理论上介绍了文化纬度的概念并运用该理论分析了中国文化,第三节介绍了中西方文化的一般差异,第四节运用淘宝和ebay两个案例对比说明文化管理在商业实践中的重要性,第五节介绍了非洲商人在广州经商的案例。第三部分是本文的结论,提出了商业管理中跨文化交际是应该遵循的基本原则和文化管理基本方法。

关键词：民族文化跨文化管理冲突管理全球化

Ornaments as Means of Efficient Reinforcement in Heritage Buildings

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Journal of Civil Engineering and Architecture 2015年第2期9卷 165-178页

作者： Randa Hassan Mohamed Abdu Wahab E1-khady Department of Architectural Engineering the Higher Institute of Engineering El Shorouk 002 Egypt Department of Architectural Engineering Collage of Engineering and Technology Arab Academy for Science Technology andMaritime Transport Port Said 002 Egypt

Heritage consists of those items people have inherited and want to keep, as they give them the sense of the past of their cultural identity, but these items, especially the buildings, could not face deteriorations during their period of life, such as the change of loads, the act of the environmental conditions, the effect of the duration time of the materials and the misuse of the occupants. They need special treatments and reinforcements to keep the structural state or to gain extra forces to receive the new loads. But the traditional ways of reinforcement do not prove endless solutions as the most means of the deteriorations from the nature. So, the liability issue is how to find the least reinforcement within the means of technology with the least deterioration and in a less time or by other ways efficiently. The hypothesis considers that the ornaments in some heritage buildings are found in critical levels of the construction which can share in an efficient way in the reinforcement processes of such buildings.

关键词： Omaments deterioration heritage significance efficient reinforcement nano-materials.

Biocidal Effect of Leaves of Crataeva religiosaForst on a Resistant Strain of Groundnut Bean Caryedon serratus(Olivier)

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Advances in Entomology 2019年第4期7卷 81-91页

作者： Aminata Gningue Toffè ne Diome khady Fall Mbacké Sembè ne Genetic Team and Population Management Department of Animal Biology Faculty of Sciences and Technology Cheikh Anta Diop University Dakar Senegal

Groundnut (Arachis hypogaea L.) is a legume that is highly coveted by West African populations, particularly those in Senegal. However, it suffers enormous damage caused by a bruchidae beetle, Caryedon serratus. This lust rests on its richness in proteins, calories and the absence of major constraints for its production. Losses recorded can reach 83% for a period of 4 months of storage. To counter this damage, several authors have looked for alternative methods to the use of synthetic insecticides, often harmful to animal populations and the environment. In this logic, we tested the biological impact of a leaf-based formulation of plants indigenous to Senegal (Crateva religiosa) on the external forms of C. serratus. In this study, analysis of the biological parameters of strain C. serratus showed low adult mortality of C. serratus. On the other hand, the extract affects the viability of eggs and larvae and fertility is reduced. The effect of the C. religiosa plant also results in reduced fertility of surviving females and a sex ratio in favor of the males causing a risk of decreasing population growth. On the other hand, there is an extension of the total development time.

关键词： Groundnut Biological Parameters Devastator Senegal

Monitoring of Anthocyanins and Colour in Electrochemically Processed Hibiscus sabdariffaJuice

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Food and Nutrition Sciences 2021年第11期12卷 1073-1087页

作者： khady Ndiaye Cheikhou Kane Omar Ben Khatab Cisse Nicolas Ayessou Codou Mar Diop Laboratoire d’électrochimie et des Procédés Membranaires ESP/UCAD Dakar Sénégal Laboratoire de Formation Continue en Industrie Agroalimentaire ESP/UCAD Dakar Sénégal

The vital role of anthocyanins in Hibiscus sabdariffa L. is now known to most consumers. The richness of anthocyanins in antioxidants, vitamin C, minerals, etc., provides Hibiscus juice with proven nutritional qualities. The health requirements of recent years have made food products with added preservatives or processed at high temperatures less popular, thus explaining the new orientations towards innovative and interdisciplinary technologies. Anthocyanins from Hibiscus sabdariffa L. are, however, sensitive to degradation factors such as temperature, light, enzymes and also oxygen. The instability of anthocyanins has long been a subject of research using classic techniques such as heat treatment, the results of which are often limited by the rapid degradation and above all the destruction of the nutritional and organoleptic qualities of the product. Oxygen dissolved in juices is so far treated by bubbling with an inert gas or by adding other molecules such as preservatives which can cause a lot of health damage. The electrochemical approach is a new stabilisation technique that reduces the dissolved oxygen in the juice, cold and without the addition of other molecules. The electrolysis of Hibiscus juice was carried out by noble electrodes (Platinum and Stainless Steel) with a well-characterised Time/Potential or Time/Intensity couple. The electroreduced samples and the control were then stored at 4°C, 25°C and 37°C for more than 6 months. Monitoring of anthocyanins in the first month, of the samples and the control, showed a significant difference of 10% between the electroreduced extract and the untreated control at 37°C, which had previously been problematic for the heat treatment and even for the other membrane techniques. Oxygen reduction on the platinum electrode/ECS allowed the retention of more than 10% of anthocyanins after 4 weeks of storage at 25°C and 37°C. At 4°C, a sign

关键词： Monitoring Anthocyanin Colour Oxygen Stabilisation Electrochemical Nafion Membrane Ratio

Back Illuminated N/P/P+Bifacial Silicon Solar Cell under Modulated Short-Wavelength: Determination of Base Optimum Thickness

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Energy and Power Engineering 2021年第5期13卷 207-220页

作者： Mamadou Sall Dianguina Diarisso Mame Faty Mbaye Fall Gora Diop Mor Ndiaye khady Loum Gregoire Sissoko Laboratory of Semiconductors and Solar Energy Physics Department Faculty of Science and Technology Cheikh Anta Diop University Dakar Senegal University Institute of Technology University of Thiès Thiès Sénégal Ecole Polytechnique de Thiès Thiès Sénégal

A bifacial silicon solar cell under monochromatic illumination in frequency modulation by the rear side is being studied for the optimization of base thickness. The density of photogenerated carriers in the base is obtained by resolution of the continuity equation, with the help of boundary conditions at the junction surface (n+/p) and the rear face (p/p+) of the base. For a short wavelength corresponding to a high absorption coefficient, the AC photocurrent density is calculated and represented according to the excess minority carrier’s recombination velocity at the junction, for different modulation frequency values. The expression of the AC recombination velocity of excess minority carriers at the rear surface of the base of the solar cell is then deduced, depending on both, the absorption coefficient of the silicon material and the thickness of the base. Compared to the intrinsic AC recombination velocity, the optimal thickness is extracted and modeled in a mathematical relationship, as a decreasing function of the modulated frequency of back illumination. Thus under these operating conditions, a maximum short-circuit photocurrent is obtained and a low-cost bifacial solar cell can be achieved by reducing material (Si) to elaborate the base thickness.

关键词： Bifacial Silicon Solar Cell AC Recombination Velocity-Base Thickness Short-Wavelength