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Dynamic of Scalar Bosons in Aharonov-Bohm Magnetic Field

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Journal of Applied Mathematics and Physics 2024年第1期12卷 268-276页

作者： Frédéric D. Y. Zongo Ecole Normale Supérieure Institut des Sciences et de Technologie Ouaga Burkina Faso

We study the dynamic of scalar bosons in the presence of Aharonov-Bohm magnetic field. First, we give the differential equation that governs this dynamic. Secondly, we use variational techniques to show that the following Schrödinger-Newton equation: , where A is an Aharonov-Bohm magnetic potential, has a unique ground-state solution.

关键词： Scalar Boson Aharonov-Bohm Magnetic Field Schrödinger-Newton Equation Ground-State Solution

Advancements on metal oxide semiconductor photocatalysts in photo-electrochemical conversion of carbon dioxide into fuels and other useful products

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Frontiers in Energy 2024年第2期18卷 187-205页

作者： Jai PRAKASH Zhangsen CHEN Shakshi SAINI Gaixia ZHANG Shuhui SUN department of Chemistry National Institute of Technology HamirpurHamirpur 177005India institut National de la Recherche Scientifique(INRS) Centre Énergie Matériaux TélécommunicationsVarennes J3X 1P7Canada department of Chemistry Indian Institute of Technology MandiHimachal PradeshIndia department of Electrical Engineering École de Technologie SupérieureMontréal H3C 1K3Canada

Due to its fascinating and tunable optoelectronic properties,semiconductor nanomaterials are the best choices for multidisciplinary ***,the use of semiconductor photocatalysts is one of the promising ways to harness solar energy for useful applications in the field of energy and *** recent years,metal oxide-based tailored semiconductor photocatalysts have extensively been used for photocatalytic conversion of carbon dioxide(CO_(2))into fuels and other useful products utilizing solar *** is very significant not only from renewable energy consumption but also from reducing global warming point of *** current research activities are promising for a better future of *** present mini-review is focused on recent developments(2–3 years)in metal oxide semiconductor hybrid photocatalysts-based photo-electrochemical conversion of CO_(2)into fuels and other useful ***,general mechanism of photo-electrochemical conversion of CO_(2)into fuels or other useful products has been ***,various metal oxide-based emerging hybrid photocatalysts including tailoring of their morphological,compositional,and optoelectronic properties have been discussed with emphasis on their role in enhancing photoelectrochemical ***,mechanism of their photo-electrochemical reactions and applications in CO_(2)conversion into fuels/other useful products have been ***,challenges and future prospects have been discussed followed by a summary.

关键词： metal-oxide semiconductors nanohybrid photocatalysts photo-electrochemical CO_(2)conversion tailoring morphology fuels challenges and future prospects

Comparative Study of Probabilistic and Least-Squares Methods for developing Predictive Models

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Open Journal of Applied Sciences 2024年第7期14卷 1775-1787页

作者： Boribo Kikunda Philippe Thierry Nsabimana Jules Raymond Kala Jeremie Ndikumagenge Longin Ndayisaba Centre de Recherche en Infrastructure Environnement et technologie (CRIET) Faculty of Engineering Sciences Universit du Burundi Bujumbura Burundi Faculty of Sciences Universit Catholique de Bukavu (UCB) Bukavu DR Congo Management Computer department Institut suprieur Pdagogique de bukavu (ISP/Bukavu) Bukavu DR Congo

This article explores the comparison between the probability method and the least squares method in the design of linear predictive models. It points out that these two approaches have distinct theoretical foundations and can lead to varied or similar results in terms of precision and performance under certain assumptions. The article underlines the importance of comparing these two approaches to choose the one best suited to the context, available data and modeling objectives.

关键词： Predictive Models Least Squares Bayesian Estimation Methods

Phytochemical Analysis and Antimicrobial Activity of Lawsonia inermis Leaf Extracts from Burkina Faso

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American Journal of Plant Sciences 2024年第7期15卷 552-576页

作者： Ollo Youl Soumaïla Konaté Ernest N. Sombié Rainatou Boly Boukaré Kaboré Moumouni Koala Arouna Zoungrana Saybou Savadogo Christian Marc Tahita Innocent Valea Halidou Tinto Adama Hilou Maminata Traoré-Coulibaly Laboratoire de Biochimie et de Chimie Applique (LABIOCA) Universit de Ouagadougou Ouagadougou Burkina Faso Agence Nationale Pour la Scurit Sanitaire de lEnvironnement de lAlimentation du Travail et des Produits de Sant (ANSSEAT) Ouagadougou Burkina Faso Laboratoire de Recherche-Dveloppement de Phytomdicaments et Mdicaments (L-RD/PM) Institut de Recherche en Sciences de la Sant (IRSS-CNRST) Ouagadougou Burkina Faso Laboratoire de Chimie Organique et de Physique Applique (LCOPA) cole Doctorale Sciences et Technologie Universit Joseph KI-ZERBO Ouagadougou Burkina Faso Laboratoire Sciences de la Vie et de la Terre (LASVT) cole Doctorale Sciences et Technologie Universit Norbert ZONGO Koudougou Burkina Faso Unit de Recherche Clinique de Nanoro Institut de Recherche en Sciences de la Sant (IRSS-CNRST) Nanoro Burkina Faso

Lawsonia inermis is a hairless plant growing in various regions of North Africa, the Indian subcontinent, and the Middle East. It possesses many medicinal attributes, including curative properties against infectious dermatoses. This study was carried out to evaluate the phytochemical profile of the crude ethanolic extract of the plant leaves and its fractions as well as their antimicrobial activities. The phytochemical profile was performed using high-performance thin-layer chromatography (HPTLC), gas chromatography-mass spectrometry (GC-MS), and high-performance liquid chromatography (HPLC). Additionally, the phenolic and flavonoid contents were determined using the Folin-Ciocalteu spectrophotometric and the aluminum trichloride methods. Antimicrobial activity was tested using disc diffusion and microdilution methods. The presence of flavonoids, tannins, sterols, and triterpenes was revealed. GC-MS detected twelve compounds main compounds consisting of saturated and unsaturated fatty acids and phenolic and terpenoid compounds among twenty-seven components. HPLC also detected high contents of phenolic acids and flavonoids. The most abundant triterpene and sterols were ursolic acid (around 43.14 g/100g DW, 13.9 g/100g dry weight (DW), and 0.68 g/100g DW) in the crude ethanolic extract of leaves (FeLi), hexane fraction (FHLi) and dichloromethane fraction (FDLi), respectively and, β-sitosterol in FeLi (56.7 mg/100g DW), FHLi (10.55 g/100g DW), FDLi (106.1 mg/100g DW) and butanol fraction (FBLi) (357.4 mg/100g DW). Among the flavonoids, rutin = 3.24 g/100g and quercetin = 0.63 g/100g in the ethanolic extract, rutin = 15.73 g/100g in the dichloromethane fraction, and rutin = 0.23 g/100g) in the aqueous fraction;and among phenolic compounds, caffeic acid (37.65 g/100g DW) and vanillic acid (22.70 g/100g DW) were the most important in the ethyl acetate fraction (FAeLi). All organic fractions exhibited interesting antibacterial and antifungal activities against the tested s

关键词： Lawsonia inermis Phytochemical Profile HPLC GC-MS Analysis Antimicrobial Activity

Ecological Wastewater Treatment System in a School Environment Using a Horizontal Flow Biological Reactor: The Case of Typha

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Journal of Environmental Protection 2024年第1期15卷 1-12页

作者： Falilou Coundoul Abdou Khafor Ndiaye Abdoulaye deme institut Polytechnique de Saint-Louis (IPSL) Universit&eacute Gaston Berger de Saint-Louis Saint-Louis S&eacuten&eacutegal UFR de Sciences Appliqué es et de Technologie Universit&eacute Gaston Berger de Saint-Louis Saint-Louis S&eacuten&eacutegal

The overarching goal of this study is to offer an effective and sustainable solution to the challenges of sanitation in rural and school settings in the northern region of Senegal. The study explores a wastewater treatment approach based on phytoremediation, with a particular focus on the use of horizontally-flowing reed bed filters. Furthermore, it aims to adapt and optimize these systems for the specific needs of Senegal, focusing on wastewater in school environments. Thus, we constructed a horizontally-flowing reed bed filter, planted with Typha, at the Ndiébène Gandiol school in Senegal. We will investigate the efficiency of wastewater treatment by this horizontally-flowing reed bed filter, emphasizing the role of the plant used: Typha. The filter is described in detail, specifying its dimensions, its composition of flint gravel, and the choice of plants, namely Typha. The experimental protocol is detailed, describing the sampling at the entrance and exit of the filter to evaluate water quality. The parameters analyzed include Chemical Oxygen demand (COD), Biochemical Oxygen demand over 5 days (BOD5), suspended solids, ammonium, nitrates, phosphates, pH, conductivity, and fecal coliforms. The results indicate a significant improvement in water quality after treatment. COD, BOD5, suspended solids, and fecal coliforms are greatly reduced, thus demonstrating the efficacy of the Typha filter. However, nitrate concentrations remain relatively stable, suggesting room for improvement in their elimination. A perspective of reuse of the treated water is considered, showing that the effluents from the planted filter meet Senegalese and international standards for irrigation. The findings suggest that these waters could be used for a variety of crops, thereby reducing the pressure on freshwater resources. In conclusion, the Typha-based filtration system shows promising results for improving water quality in this region of Senegal. However, adjustments are necessary for mor

关键词： Hydraulic Engineering Wastewater Quality Wastewater Treatment Agricultural Irrigation Sanitation Engineering Environment

Quantitative Comparative Study of the Performance of Lossless Compression Methods Based on a Text Data Model

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Open Journal of Applied Sciences 2024年第7期14卷 1944-1962页

作者： Namogo Silué Sié Ouattara Mouhamadou Dosso Alain Clément Laboratoire des Sciences et technologies de la Communication et de lInformation (LSTCI) Institut National Polytechnique Houphout Boigny (INPHB) Yamoussoukro Cte dIvoire institut National Polytechnique Houphout Boigny (INPHB) Yamoussoukro Cte dIvoire UFR Mathmatique-Informatique Ecole Doctorale Sciences-Technologie et Agriculture Durable (ED STAD) Universit Felix Houphout-Boigny (UFHB) Abidjan Cte dIvoire Ecole de Gomatique et du Territoire (EGT) Abidjan Cte dIvoire LARIS SFR MATHSTIC Universit dAngers Angers France

Data compression plays a key role in optimizing the use of memory storage space and also reducing latency in data transmission. In this paper, we are interested in lossless compression techniques because their performance is exploited with lossy compression techniques for images and videos generally using a mixed approach. To achieve our intended objective, which is to study the performance of lossless compression methods, we first carried out a literature review, a summary of which enabled us to select the most relevant, namely the following: arithmetic coding, LZW, Tunstall’s algorithm, RLE, BWT, Huffman coding and Shannon-Fano. Secondly, we designed a purposive text dataset with a repeating pattern in order to test the behavior and effectiveness of the selected compression techniques. Thirdly, we designed the compression algorithms and developed the programs (scripts) in Matlab in order to test their performance. Finally, following the tests conducted on relevant data that we constructed according to a deliberate model, the results show that these methods presented in order of performance are very satisfactory:- LZW- Arithmetic coding- Tunstall algorithm- BWT + RLELikewise, it appears that on the one hand, the performance of certain techniques relative to others is strongly linked to the sequencing and/or recurrence of symbols that make up the message, and on the other hand, to the cumulative time of encoding and decoding.

关键词： Arithmetic Coding BWT Compression Ratio Comparative Study Compression Techniques Shannon-Fano Huffman Lossless Compression LZW Performance Redundancy RLE Text Data Tunstall

Indirect Electroanalysis of 3-Methyl-4-Nitrophenol in Water Using Carbon Fiber Microelectrode Modified with Nickel Tetrasulfonated Phthalocyanine Complex

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Materials Sciences and Applications 2024年第2期15卷 25-35页

作者： Yibor Fabrice Roland Bako Serge Foukmeniok Mbokou Boukaré Kaboré Issa Tapsoba Maxime Pontié Laboratoire de Chimie Analytique Environnementale et Bio-organique (LCAEBiO) Département de Chimie Université Joseph Ki-Zerbo Ouagadougou Burkina Faso institut des Sciences et de technologie Ecole Normale Supérieure Ouagadougou Burkina Faso Group of analysis and Processes Analysis (GA&P) Département de Chimie Université d’Angers Angers France Laboratoire de Sciences et technologies (LaST) Université Thomas SANKARA Ouagadougou Burkina Faso

Electrochemical detection of 3-methyl-4-nitrophenol (MNP) in direct phenol oxidation occurs at high potentials and generally leads to progressive passivation of the electrochemical sensor. This study describes the use of a carbon fiber microelectrode modified with a tetrasulfonated nickel phthalocyanine complex for the detection of MNP at a lower potential than that of direct phenol oxidation. The MNP voltammogram showed the presence of an anodic peak at -0.11 V vs SCE, corresponding to the oxidation of the hydroxylamine group generated after the reduction of the nitro group. The effect of buffer pH on the peak current and SWV parameters such as frequency, scan increment, and pulse amplitude were studied and optimized to have better electrochemical response of the proposed sensor. With these optimal parameters, the calibration curve shows that the peak current varied linearly as a function of MNP concentration, leading to a limit of detection (LoD) of 1.1 μg/L. These results show an appreciable sensitivity of the sensor for detecting the MNP at relatively low potentials, making it possible to avoid passivation phenomena.

关键词： 3-Methyl-4-Nitrophenol Carbon Fiber Microelectrode Nickel Tetrasulfonated Phthalocyanine Indirect Electroanalysis Square Wave Voltammetry

Investigating the Impact of Base Heating and External Electric Field on PV Cell Performance under Intense Illumination

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Open Journal of Applied Sciences 2024年第5期14卷 1305-1314页

作者： Boubacar Soro Guy Serge Tchouadep Esso-Ehanam Tchedre Kpeli Ousmane Souliga Adama Ouedraogo Issa Zerbo Martial Zoungrana Laboratory of Thermal and Renewable Energies Universit&#233 Joseph KI-ZERBO Ouagadougou Burkina Faso institut des Sciences et technologie Ecole Normale Sup&#233rieure Ouagadougou Burkina Faso

The characterization of the performances of a PV cell is linked to intrinsic factors of this cell. It is therefore important for us to identify the favorable or unfavorable conditions that affect the performance of PV cells. It is from this perspective that it seems judicious to us to study the simultaneous influence of the heating of the base and an external electric field on the performance of a PV cell under intense illumination of 50 suns. Two phenomena contribute to the heating of the base of a PV cell which is heating due to the transfer by conduction of solar radiation energy received by the surface of the PV cell and the heat generated inside the PV cell by various phenomena linked to the movement of photogenerated charged carriers. In this study, we take into account the heating linked to the movement of the charged carriers in the base. After a mathematical modeling of the PV cell considered, some hypotheses are formulated and the expressions of the electrical parameters are established as a function of the electric field and base temperature. Subsequently, we use numerical simulation to highlight the behavior of theses parameters as a function of temperature and of the intensity of the electric field. The results show that for any given temperature, the orientation of the electric field as considered in our work improves the performance of the PV cell while high temperatures degrade these performances. Furthermore, the analysis of the curves shows that the harmful effect of temperature on the performance of a PV cell is more accentuated at large values of electric field.

关键词： Collisions Thermalization Braking Electric Strength Base Temperature

Insight from Lithostructural and Aeromagnetic Data from the Léo Square degree, Central-Western Burkina Faso

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Open Journal of Geology 2024年第1期14卷 19-28页

作者： Adama Ouédraogo Yaméogo Pascal Ouiya Gounwendmanaghré Hubert Zongo Omar Akonyiré Abraham Seydoux Traoré Saga Sawadogo Séta Naba Unité de Formation et de Recherche en Sciences et technologies Département des Sciences de la Vie et de la Terre Université Norbert Zongo Koudougou Burkina Faso Unité de Formation et de Recherche en Sciences de la Vie et de la Terre Laboratoire Géosciences et Environnement (LaGE) Département des Sciences de la Terre Université Joseph Ki-Zerbo Ouaga Burkina Faso Ecole Normale Supérieure (ENS)/institut des Sciences et de technologie (IST) Ouaga Burkina Faso Ecole Supérieure d’Ingénieries Université de Fada N’gourma Fada N’Gourma Burkina Faso

This study, carried out in the Léo square degree (west-central Burkina Faso) in the Palaeoproterozoic domain of the Man/Léo ridge, aims to define the shapes and positions of granitic plutons and the organisation of deformation structures using aeromagnetic data. These data have shown that there are small sub-circular granitic bodies to the north of the granitic masses in this region, and a large sub-circular granitic body to the south, around which are other smaller granitic bodies. The lineament map shows that the deformation structures are organised along three main directions and largely form these sub-circular plutonic bodies. We suggest that the granitic plutons are coalescent, pending identification of the internal structures of these granites to further refine the geodynamic model.

关键词： Burkina Faso Lineaments Belts Rocks Leo’s Leaf Granitoïd Airbornes Magnétics