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Nutritional and Sanitary Quality of Infant Flours Produced in Ouagadougou, Burkina Faso

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Food and Nutrition Sciences 2024年第8期15卷 727-743页

作者： léa Kilô Adam Bayala-Yaï Philippe Augustin Nikièma Hassane Sangaré Fabrice Bationo Imael Henri Nestor Bassolé Jacques Simpore laboratoire de Biologie molculaire et de Gntique (lABIOGenE) Universit Joseph KI-ZERBO Ouagadougou Burkina Faso laboratoire de Biologie molculaire dEpidmiologie et Surveillance des Agents Transmissibles par les Aliments (LaBESTA) Universit Joseph KI-ZERBO Ouagadougou Burkina Faso laboratoire de microbiologie et de Physicochimie du Dpartement de Technologie Alimentaire (DTA) Institut de Recherche en Sciences Appliques et Technologies (IRSAT) Ouagadougou Burkina Faso

The quality of infant flours used during the weaning age is of great importance in that it conditions the nutritional health of infants and young children. This study aimed to assess the nutritional and sanitary quality of infant flours produced in the city of Ouagadougou. This was a cross-sectional study including 11 out of 25 infant flour production units that gave their consent to partake in the study. In total, 25 infant flour samples have been collected from July to September 2021. The physicochemical and microbiological parameters were determined according to standard methods. The ANOVA analysis of variance showed significant differences between the means of the physico-chemical and the means of the microbiological parameters respectively. The results showed that 60% of proteins and 80% of lipid and total carbohydrate contents were below the authorised limits. The energy values were below the authorised limit in 88% of the cases. All instant infant flours had microbiological loads compliant with Burkinabè standards. As for infant flour to be cooked, 63.64% and 81.82% had satisfactory numbers of total coliforms and faecal coliforms respectively. Staphylococcus aureus and Escherichia coli were detected in these samples with 86.36% of infant formulae having results below the recommended limit. These results show that the infant flours produced in Ouagadougou were somehow of acceptable quality. However, there is a need to improve the formulae for macronutrient contents, energy values and sanitary quality to comply with the recommendations.

关键词： Nutritional and Sanitary Quality Infant Flours Ouagadougou Burkina Faso

Theoretical and Experimental Quantification of Solar Radiation through a Tracking System

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Open Journal of Applied Sciences 2024年第9期14卷 2648-2660页

作者： Guy Christian Tubreoumya Eloi Salmwendé Tiendrebeogo Tchardja Combary Téré Dabilgou Jacques Nebié Boubou Bagré Alfa Oumar Dissa Antoine Bere laboratoire de Physique et de Chimie de lenvironnement (lPCE) Universit Joseph KI-ZERBO Ouagadougou Burkina Faso laboratoire de mathmatiques et PhySique (lA.m.P.S) Universit de Perpignan Via Domitia (UPVD) Perpignan France

This work deals with the estimation of solar radiation through a solar tracker aimed at evaluating the effect of solar tracking on the solar deposit in Burkina Faso. Using a two-axis solar tracking system, we experimentally measured solar radiation at our Joseph KI-ZERBO University site and compared it with that obtained by a numerical simulation run using Fortran programming software based on a mathematical model by Brichambaut. The results obtained from the mathematical and experimental studies show that, with a solar tracker, on a clear-sky day, solar irradiation is between 800 W·m−2 and 1000 W·m−2 between about 8 a.m. and 4 p.m., i.e. a duration of 8 hours of insolation. Analysis of the numerical and experimental results shows very good quantitative and qualitative agreement, with an average relative error of 18%.

关键词： Tracking System Solar Radiation Dual Axis energy Efficiency

Finite-temperature ductility-brittleness and electronic structures of Al_(n)Sc(n=1,2 and 3)

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Rare metals 2024年第8期43卷 3974-3989页

作者： Xue-Qian Wang Ying Zhao Hao-Xuan liu Shu-Chen Sun Hong-Bo Yang Jia-min Zhong Gan-Feng Tu Song li Yu-Dong Zhang Claude Esling Hai-le Yan liang Zuo Key laboratory for Anisotropy and Texture of materials(ministry of Education) School of Material Science and EngineeringNortheastern UniversityShenyang 110819China School of metallurgy Northeastern UniversityShenyang 110819China Rare Earth Functional materials(Xiong'an)Innovation Center Co. Ltd.Xiong'an 071700China laboratoire d'étude des microstructures et de mécanique des matériaux(lEm3) Unikersitéde Lorraine57045MetzFrance

Finite-temperature ductility-brittleness and electronic structures of Al_(3)Sc,Al_(2)Sc and AlSc are studied comparatively by first-principles calculations and ab initio molecular *** show that Al_(3)Sc and Al_(2)Sc are brittle at both ground state and finite temperatures,while AlSc possesses a significantly superior *** ground state,AlSc is ductile from Pugh's and Poisson's criteria,while it is brittle in Pettifor's *** ductility of all Al_(3)Sc,Al_(2)Sc and AISc improves greatly with the elevated ***,the Cauchy pressure of AlSc undergoes a transition from negative to *** T>600 K,AlSc is unequivocally classified as ductile from all criteria *** all compounds,the Al-Al bond originated from s-p and p-p orbital hybridizations,and the Al-Sc bond dominated by p-d covalent hybridization,are the first and second strongest chemical bonds,*** explain the difference in mechanical properties,the mean bond strength(mBS)is introduced in this *** weaker Al-Al bond in AlSc,leading to a smaller mBS,could be the origin of the softer elastic stiffness and superior intrinsic *** longer length of the Al-Al bond in AlSc is responsible for its weaker bond ***,the enhanced metallicity of the Al-Al bond in AlSc would also contribute to its exceptional *** longer length of the Al-Al bond in AISc is responsible for its weaker bond ***,the enhanced metallicity of the Al-Al bond in AlSc would also contribute to its exceptional ductility.

关键词： Al-Sc Target materials Intrinsic ductility Finite-temperature elastic constant First-principles calculation

Petrographic and Geochemical Characters of Granites of the Banfora Belt, Burkina Faso (West Africa)

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International Journal of Geosciences 2024年第9期15卷 682-697页

作者： Abdoulaye Ouedraogo Seta Naba Hermann Ilboudo laboratoire Gosciences et environnement (laGE) Dpartement des Sciences de la Terre Unit de Formation et de Recherche en Sciences de la Vie et de la Terre Universit Joseph KI-ZERBO Ouagadougou Burkina Faso Bureau des mines et de la Gologie du Burkina (BUmIGEB) Ouagadougou Burkina Faso

The Banfora’s birimian greenstones belt is located in the western part of Burkina Faso (west Africa). Recent petrographic and lithogeochemical studies have highlighted plutons intruding the metasedimentary and metavolcanic series. These plutonic rocks are composed of leucogranites belonging to the so-called Ferkessedougou’s or Ferké’s batholith, granites, granodiorites, monzodiorites and quartz monzonites. From the lithogeochemical studies, these plutonic rocks have a calc-alkaline and peraluminous character. The rare earth elements spectra of the Ferké’s leucogranites let distinguished two sub-facies. One of the sub-facies is composed of quartz monzonite to granite, while the other is granitic sensu stricto. However, all these plutonic rocks were emplaced in a geodynamic context of subduction followed by collision.

关键词： Burkina Faso Banfora Greenstones Belt Plutons Geodynamic Context Subduction

Acute Toxicity and Anthelmintic Effects of Gomphrena serrata l. (Amaranthaceae) Extracts on Adult Worms and Eggs of Haemonchus contortus

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Pharmacology & Pharmacy 2024年第5期15卷 207-221页

作者： Hippolyte Ouedraogo mohamed Bonewendé Belemlilga Aristide Traore Gilchrist Abdoul laurent Boly Félicité moyenga Gueswindé Geoffroy Ouedraogo Sylvain Ilboudo lazare Belemnaba Sylvin Ouedraogo laboratoire de recherche-Dé veloppement de Phytom&#233dicaments et M&#233dicaments (LR-D/PM) Institut de Recherche en Sciences de la Sant&#233 (IRSS) Centre National de la Recherche Scientifique et Technologique (CNRST) Ouagadougou Burkina Faso laboratoire de Dé veloppement du M&#233dicament (LADME) Centre de Formation deRecherche et d&#8217Expertises en Sciences du M&#233dicament (CEA-CFOREM) &#201cole Doctorale Sciences de la Sant&#233 (ED2S) Universit&#233 Joseph KI-ZERBO Ouagadougou Burkina Faso International Research laboratory-environnement Sant&#233 Soci&#233t&#233s (IRL 3189 ESS) CNRS/CNRST/UCAD/UGB/USTTB Ouagadougou Burkina Faso

Gomphrena serrata l. (Amaranthaceae) is a medicinal plant widely used traditionally in rural areas to treat many diseases, including gastrointestinal helminthiasis of small ruminants. This work aims to estimate the plant extracts phytochemical potential and study the activities of the aqueous decoction (GS_AD), aqueous macerate (GS_Am), and hydroalcoholic macerate (GS_HEm) of Gomphrena serrata extracts on two developmental stages (eggs and adult worms) of Haemonchus contortus. Phytochemical screening was carried out. The acute toxicity test was performed according to the Organisation for Economic Co-operation and development (OECD) test guideline 423. The Haemonchus contortus eggs hatching inhibition test was performed left to incubate for 48 hours in the presence of the different plant extracts at increasing concentrations of 0.125;0.25;0.5;0.625;1;2;3 mg/ml. For the motility inhibition test on adult worms, the worms were contacted with the extracts at concentrations of 0.75;1;1.25;1.5;2;3;4 mg/ml and left to incubate for 24 hours. Albendazole and levamisole were used as standard. Phytochemical screening revealed the presence of tannins, saponins, reducing compounds, coumarins and derivatives, anthocyanins, steroids, triterpenes, and flavonoids. An acute toxicity study showed that the oral lD50 value of G. serrata was estimated to be 5000 mg/kg. All extracts showed an effect on both stages of parasite development. The hatching inhibition rate was 100% from 3 mg/ml for all three extracts. The rate of inhibition of motility was 100% from 4 mg/ml for each extract. HEm is more efficient on eggs and Haemonchus contortus adult worms than other extracts with IC50 of 0.457 mg/ml and lC50 of 1.329 mg/ml, respectively. These results suggest that Gomphrena serrata, a plant used by farmers, has anthelmintic properties.

关键词： Gomphrena serrata Haemonchus contortus Anthelmintic In Vitro

Performance Evaluation of Solar Chimney Draft: Application to Ventilation

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Smart Grid and Renewable energy 2024年第4期15卷 107-122页

作者： Boukaré Ouedraogo Adama Ouedraogo Arouna Kabore Kalifa Palm Dieudonné Joseph Bahiebo laboratoire denergies Thermiques Renouvelables (letRE) Universit Joseph KI-ZERBO: UFR/SEA Ouagadougou Burkina Faso laboratoire de Chimie Analytique Physique Spatiale et Energtique (LACAPSE) Universit Norbert ZONGO Koudougou Burkina Faso Centre Universitaire Polytechnique de Kaya (CUP-Kaya) Universit Joseph KI-ZERBO Ouagadougou Burkina Faso laboratoire des Systmes denergie Renouvelable et environnement Institut de Recherche en Sciences Appliques et Technologies (IRSAT) Centre National de la Recherche Scientifique et Technologique (CNRST) Ouagadougou Burkina Faso

Ventilation is one of the factors contributing to energy consumption in buildings and food preservation. The solar chimney proves to be an alternative for reducing conventional energy consumption. Thus, in this study, the performance of a solar chimney with two active faces for thermally drawing air from a chamber for preserving agri-food products was evaluated. These performances were experimentally assessed through data measurements: temperatures and velocities within the chimney, and their analysis using Excel and mATlAB. The obtained results were compared with those from literature to verify their validity. From this study, it is found that the maximum temperature at the chimney outlet reaches 49.4˚C with an average value of 43.7˚C. Additionally, the heating evolution of the chimney air presents four (04) identical phases in pairs, reflecting the chimney’s operation throughout day. The temperature difference between the outlet and inlet of the chimney reaches a maximum of 17˚C with an average of 12.6˚C. Regarding airflow, the maximum air velocity at the chimney outlet is 0.8 m/s, and the average velocities have consistently been greater than or equal to 0.46 m/s. Thus, it can be concluded that the solar chimney is capable of providing ventilation for the preservation chamber through thermal draft.

关键词： Solar Chimney Natural Ventilation Thermal Draft Airflow Chimney Effect

Improvement of mechanical Qualities of Clay material through Coconut Fiber Stabilization

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materials Sciences and Applications 2024年第7期15卷 201-212页

作者： Boukaré Ouedraogo Abdoulaye Compaore moumouni derra Kalifa Palm Dieudonné Joseph Bahiebo laboratoire denergies Thermiques Renouvelables (letRE) Universit Joseph KI-ZERBO Ouagadougou Burkina Faso laboratoire Chimie Analytique de Physique Spatiale et Energtique Universit Norbert ZONGO Koudougou Burkina Faso Institute de recherche en Sciences Appliques et Technologies (IRSAT/CNRST) Ouagadougou Burkina Faso laboratoire de matriaux et environnement (lAmE) Universit Joseph KI-ZERBO Ouagadougou Burkina Faso

The criticisms regularly formulated towards clay or soil, in general, are its weak mechanical qualities and low water quality. Therefore, it is necessary to find techniques to improve the properties of this material, which is widely used worldwide. Here, we propose stabilizing clay with coconut fiber as a solution to enhance its mechanical properties. To do this, we used an experimental method, first determining the geotechnical properties of the clay and then its mechanical properties. The geotechnical study using the Proctor Test revealed that the dry density of the clay is γb = 1.42 g/cm3, and its water content is W = 22.3%. By applying the rolling method, the Atterberg limits were determined: liquid limit Wl = 63.6, plastic limit Wp = 27.9, plasticity index Ip = 35.7, and consistency index Ic = 1.46. With 25 P = 35.7 1.3, according to the water classification, it falls into class A3ts. The mechanical part focused on compression and flexural strengths obtained using a PROetI hydraulic press. We obtained a flexural strength of 0.63 mPa for simple clay (BA);0.89 mPa for clay + 0.25% fiber (BAF1/4);1.68 mPa for clay + 0.5% fiber (BAF1/2);1.87 mPa for clay + 0.75% fiber (BAF3/4);and 3.91 mPa for clay + 1% fiber (BAF1). As for the compression strength, BA = 5.90 mPa, BAF1/4 = 6.395 mPa, BAF1/2 = 6.292 mPa, BAF3/4 = 6.065 mPa, and BAF1 = 5.423 mPa. The addition of fiber has thus improved the mechanical qualities of the simple clay. These stabilized bricks can be used for sustainable and bioclimatic construction, providing higher durability and good comfort.

关键词： Compression Strength Flexural Strength Coconut Fiber Clay Geotechnical Properties

Experimental Investigation of the Stability of the Performance Characteristics of a Photovoltaic module in the Face of environmental and meteorological Factors

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Open Journal of Applied Sciences 2024年第2期14卷 589-608页

作者： Adingra Paul Arsène Kouassi Siaka Touré Diakaridja Traoré laboratoire des Sciences de la matière de l’Environnement et de l’Energie Solaire (LASMES) Unité de Formation et de Recherche des Sciences des Structures de la Matière et Technologie (UFR-SSMT) Université Félix Houphou&#235t Boigny Abidjan C&#244te d’Ivoire

The explosive technological improvement of photovoltaic systems as well as the necessity of populations to come to less expensive energy sources, that have led to an implosion at the level of solar panel manufacturers. This causes a large flow of these equipments to developing countries where the need is high, without any quality control. That conducted an experimental investigation on the performance characteristics of a 250 wp monocrystalline silicon photovoltaic module in other to check the verification and quality control. most of these PV panels which often have missing informations are manufactured and tested in places that are inadequate for our environmental and meteorological conditions. Also, their influences on the stability of internal parameters were evaluated in order to optimize their performance. The results obtained at maximum illumination (1000 w/m2) confirmed those produced by the manufacturer. The analysis of these characteristics showed that the illumination and the temperature (meteorological factors) influenced at most the stability of the internal characteristics of the module in the sense that the maximum power increased very rapidly beyond 750 w/m2 but a degradation of performance was accentuated for a temperature of the solar cells exceeding 50°C. The degradation coefficients were evaluated at -0.0864 V/°C for the voltage and at -1.6248 w/°C for the power. The 10° inclination angle of the solar panel proved to be ideal for optimizing overall efficiency in practical situations.

关键词： Renewables energies Instruments Internal Parameters of Photovoltaic Panel monocrystalline Photovoltaic Panel Solar energy Production energy Intermittence

Analysis of the Effect of Temperature and Relative Humidity on the Reliability of a Photovoltaic module

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Advances in materials Physics and Chemistry 2024年第8期14卷 165-177页

作者： Abdoulaye Kabré Dominique Bonkoungou Zacharie Koalaga Dpartement de Physique Laboratoire de Matriaux et Environnement (LA.M.E)-UFR/SEA Universit Joseph Ki-ZERBO Ouagadougou Burkina Faso

Photovoltaic energy occupies a significant place in the renewable energy market, with photovoltaic (PV) modules playing a vital role in converting solar energy into electricity. However, their effectiveness is likely to be affected by variations in environmental conditions, including temperature and relative humidity. The study examines the impact of these major climatic factors on the reliability of PV modules, aiming to provide crucial information for optimizing and managing these systems under varying conditions. Inspired by Weibull’s law to model the lifespan of components, we proposed a mathematical model integrating a correction factor linked to temperature and relative humidity. Using this approach, simulations in matlab Simulink reveal that increasing temperature and relative humidity have an adverse impact on the reliability and lifespan of PV modules, with a more pronounced impact on temperature. The results highlight the importance of considering these environmental parameters in the management and optimization of photovoltaic systems to ensure their long-term efficiency.

关键词： Solar energy PV module lifespan Reliability Efficiency