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Modelling and Sizing of a Floor Reinforced by Ballasted Columns Intended to Support a Tank

open Journal of Civil Engineering 2024年第3期14卷 405-420页

作者： cheikh dial.o diène Madièye Fall Souka Bidzha Harlin Sylvaire Laboratory of Modelling and Soil Mechanics Electrical and Building School (ESEBAT) Dakar Senegal

This work aims to study the modeling and sizing of a floor reinforced by ballasted columns. We are studying the system of reinforcement by ballasted columns because this technique is able to replace deep foundations that are technically difficult to realize and their cost is higher. The modelling and dimensioning of foundations on a ballasted column will be an important contribution to the state of the art of this method because it will highlight the mode of transfer of loads, and will expose the induced deformations by also allowing to verification criteria of bearing capacity and allowable settlement according to geometric information of the model. The columns on a substrate located at 9 m have a length of 9 m and a diameter of 40 cm and were obtained by incorporating ballast of granular class 0/31.5 of internal friction angle of 38˚ and a density weight of 21 kN/m3. The choice of this method is based on the geotechnical characteristics of the initial soil. Thus, identification and characterization tests were carried out to estimate the bearing capacity and the settlement giving respectively 125 kPa and 57 cm. These results show the ground does not have sufficient mechanical properties to withstand the loads transmitted by the tank. By adopting the reinforcement of the soil with ballasted columns, numerical calculations show that after applying a load equal to 265.1 KPa, 20 cm vertical settlement and 17 cm horizontal displacement were obtained. This is in the tolerable deformation range for our tank, namely, less than 20 cm. Analytically, in addition to reducing settlement, ballasted columns, Due to their high stiffness, they have effectively contributed to the increase of the permissible soil stress up to 257 kPa.

关键词： Reinforcement Ballasted Columns Reservoir Geotechnical Modeling Plaxis 2D

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Study of the Efficiency of Vertical Drains by an FEM Method in Soil Treatment for Road Projects: Case of the Development and Bitumination Works of the RoCADE Porto-Novo in Benin

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open Journal of Civil Engineering 2024年第3期14卷 435-455页

作者： cheikh dial.o diène Vitouley Kossi Ghyslain Joël Mamadou Tine Apanda Mbongote Johnny Laboratory of Modelling and Soils Mechanics TRU Engineering Sciences (UFR SI) University Iba Der Thiam Thies Senegal Laboratory of Modelling and Soils Mechanics School of Electrical and Building (ESEBAT) Dakar Senegal

This article aims to study the efficiency of coupled vertical drains for the treatment of long-lasting compressible clay soils for the road project platform of the ring road of Porto Novo, capital of Benin. The experimental data allowed us to estimate a consolidation of 29% in 9 months, justifying the drainage of the soil. In order to study the efficiency of drainage, a FEM model was proposed simulating different scenarios. These include a drainless road, pavements equipped with vertical drains with meshes of 0.5 m 0.5 m, 1 m 1 m and 1.5 m 1.5 m respectively and horizontal drains. The results expressed in terms of variations in vertical stresses, effective stresses and shear deformations revealed significant variations in pavement performance depending on the mesh size of the vertical drains. The configuration with a mesh of 0.5 m 0.5 m showed the least deformations, thus indicating a reduction in deformations and better stress distribution. However, the other mesh configurations showed variable results, underlining the importance of choosing the right mesh for the specific project conditions.

关键词： Pavement Vertical Drains Horizontal Drains Modelling Plaxis2D RoCADE de Porto-Novo

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Hexavalent Chromium Cr (VI) Removal from Water by Mango Kernel Powder

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Journal of Materials Science and Chemical Engineering 2024年第1期12卷 84-103页

作者： Amadou Sarr Gning cheikh Gaye Antoine Blaise Kama Pape Abdoulaye diaw diène diégane Thiare Modou Fall Laboratoire de Chimie Physique organique et d’Analyses Environnementales (LCPoAE) Université Cheikh Anta Diop Dakar Sénégal Equipe Chimie des Matériaux Inorganique et organique (ECMIo) Université Alioune Diop Bambey Sénégal Equipe des Matériaux Electrochimie et Photochimie Analytiques (EMEPA) Université Alioune Diop Bambey Sénégal Laboratoire de Photochimie et d’Analyse (LPA) Université Cheikh Anta Diop Dakar Sénégal

Metal trace elements (MTE) are among the most harmful micropollutants of natural waters. Eliminating them helps improve the quality and safety of drinking water and protect human health. In this work, we used mango kernel powder (MKP) as bioadsorbent material for removal of Cr (VI) from water. Uv-visible spectroscopy was used to monitor and quantify Cr (VI) during processing using the Beer-Lambert formula. Some parameters such as pH, mango powder, mass and contact time were optimized to determine adsorption capacity and chromium removal rate. Adsorption kinetics, equilibrium, isotherms and thermodynamic parameters such as ΔG˚, ΔH˚, and ΔS˚, as well as FTIR were studied to better understand the Cr (VI) removal process by MKP. The adsorption capacity reached 94.87 mg/g, for an optimal contact time of 30 min at 298 K. The obtained results are in accordance with a pseudo-second order Freundlich adsorption isotherm model. Finally FTIR was used to monitor the evolution of absorption bands, while Scanning Electron Microscopy (SEM) and Energy dispersive X-ray Spectroscopy (EDS) were used to evaluate surface properties and morphology of the adsorbent.

关键词： Adsorption Chromium Mango Kernel Powder Spectroscopy Analysis Water Treatment

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overall Assessment of Heat Transfer for a Rarefied Flow in a Microchannel with obstacles Using Lattice Boltzmann Method

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工程与科学中的计算机建模(英文) 2024年第1期138卷 273-299页

作者： Siham Hammid Khatir Naima omolayo M.Ikumapayi cheikh Kezrane Abdelkrim Liazid Jihad Asad Mokdad Hayawi Rahman Farhan Lafta Rashid Naseer Ali Hussien Younes Menni Laboratory of Development in Mechanics and Materials(LDMM) Zian Achour UniversityDjelfaPB 3117Algeria Department of Technology University Center Salhi Ahmed Naama(Ctr.Univ.Naama)P.O.Box 66Naama45000Algeria Department of Mechanical and Mechatronics Engineering Afe Babalola University Ado Ekiti360101Nigeria Departement of Physics Faculty of ScienceAbou Bekr Belkaid UniversityTlemcen13000Algeria Department of Physics Faculty of Applied SciencesPalestine Technical University-KadoorieTulkarmPalestine Aeronautical Technical Engineering Al-Farahidi UniversityBaghdad10011Iraq Mechanical Engineering Department University of KerbalaKarbala56001Iraq Information and Communication Technology Research Group Scientific Research CenterAl-Ayen UniversityThi-QarIraq National University of Science and Technology Dhi QarIraq

The objective of this investigation is to assess the effect of obstacles on numerical heat transfer and fluid flow momentum in a rectangular microchannel(MC).Two distinct configurations were studied:one without obstacles and the other with alternating obstacles placed on the upper and lower *** research utilized the thermal lattice Boltzmann method(LBM),which solves the energy and momentum equations of fluids with the BGK approximation,implemented in a Python coding *** jump and slip velocity conditions were utilized in the simulation for the MC and extended to all obstacle *** study aims to analyze the rarefaction effect,with Knudsen numbers(Kn)of 0.012,0.02,and *** outcomes indicate that rarefaction has a significant impact on the velocity and temperature *** presence of nine obstacles led to slower fluid movement inside the microchannel MC,resulting in faster cooling at the *** MCs with obstacles,the rarefaction effect plays a crucial role in decreasing the Nusselt number(Nu)and skin friction coefficient(Cf).Furthermore,the study demonstrated that the obstacles played a crucial role in boosting fluid flow and heat transfer in the *** findings suggest that the examined configurations could have potential applications as cooling technologies in micro-electro-mechanical systems and microdevice applications.

关键词： Microfluid rarefied flow LBM microchannel Knudsen number numerical simulation

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Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry traces the geographical source of Biomphalaria pfeifferi and Bulinus forskali,involved in schistosomiasis transmission

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Infectious diseases of Poverty 2024年第1期13卷 98-99页

作者： Papa Mouhamadou Gaye EI Hadj Ibrahima Ndiaye Souleymane Doucoure Doudou Sow Mapenda Gaye Ndiaw Goumballa Carole Cassagne Coralie L'ollivier oleg Medianikov cheikh Sokhna Stephane Ranque Aix-Marseille University IRD AP-HM SSA VITROME Marseille France VITRoME International IRD-UCAD Campus Dakar Senegal Hospital-University Institut (IHU) Mediterranée Infection Marseille France Departement of Animal Biology Faculty of Sciences and Techniques UCAD Dakar Senegal Department of Parasitology-Mycology UFR Sciences de la Santé Université Gaston Berger Saint-Louis Senegal

Background Freshwater snails of the genera Bulinus spp.,Biomphalaria spp.,and oncomelania *** the main intermediate hosts of human and animal *** of these snails has long been based on mor-phological and/or genomic criteria,which have their *** limitations include a lack of precision for the morphological tool and cost and time for the DNA-based ***,Matrix-Assisted Laser Desorp-tion/lonization Time-of-Flight(MALdi-ToF)mass spectrometry,a new tool used which is routinely in clinical microbi-ology,has emerged in the field of malacology for the identification of freshwater *** study aimed to evaluate the ability of MALdi-ToF MS to identify Biomphalaria pfeifferi and Bulinus forskali snail populations according to their *** This study was conducted on 101 *** and 81 *** snails collected in three distinct geo-graphical areas of Senegal(the North-East,South-East and central part of the country),and supplemented with wild and laboratory *** which had previously been morphologically described were identified by MALDl-ToF MS[identification log score values(LSV)≥1.7],after an initial blind test using the pre-existing *** DNA-based identification,new reference spectra of ***(n=10)and ***(n=5)from the geographical areas were added to the MALdi-ToF spectral *** final blind test against this updated database was per-formed to assess identification at the geographic source *** MALdi-ToF MS correctly identified 92.1%of 101 *** snails and 98.8%of 81 *** *** the final blind test,88%of 166 specimens were correctly identified according to both their species and sampling site,with LSVs ranging from 1.74 to *** geographical source was adequately identified in 90.1%of 91 *** and 85.3%of 75 *** *** our findings demonstrate that MALdi-ToF MS can identify and differe

关键词： Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry Snail Intermediate host Biomphalaria pfeifferi Bulinus forskali Schistosomiasis Senegal

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Management of Acute Bowel obstruction in Adults in Ziguinchor Hospital Establishments: About 163 Cases Followed Up

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Surgical Science 2024年第4期15卷 207-218页

作者： omar Sow cheikh H. Badji Mouhamed dieng Reymond Seydi Aissata dial.o cheikh diouf Papa A. Ba Boubacar Fall Department of General Surgery Peace Hospital Assane Seck University of Ziguinchor Ziguinchor Senegal Department of General Surgery Central Regional Hospital of Ziguinchor Assane Seck University of Ziguinchor Ziguinchor Senegal Department of General Surgery University of Iba Der Thiam Thies Senegal

Acute intestinal obstruction represents a very frequent admission to surgical emergencies. The aim of our study was to make a descriptive analysis of the management of acute intestinal obstructions at the level of hospital establishments in Ziguinchor. Materials and Methods: This was a retrospective, descriptive, multicenter study from the period of January 1, 2017 to December 31, 2021. Patients over 15 years of age admitted for occlusive syndrome in the two surgical departments of the Ziguinchor regional hospitals were included in the study. Epidemiological, diagnostic, therapeutic and evolutionary data were studied. Results: Acute intestinal occlusions accounted for 8.3% of admissions. A total of 163 patients were enrolled, 61.9% were men, sex ratio of 1.6. The mean age was 48.7 years. The average consultation time was 74.8 hours (3.12 days). The total occlusive syndrome was in 48.5% of the cases. Abdominal pain was present in 87.1%, vomiting in 74.2%, cessation of matter and gas in 60.7% and meteorism in 36.2%. Biological lab tests reported hyperleukocytosis in 28.1% of the cases. Abdominal CT scans were performed in 71.2%, confirming the diagnosis in 90.5% and determining the etiology in 93.1%. The zone of the obstruction in the small bowel was 62.7%, and in the colon in 37.3%. Functional occlusions accounted for 22.7% of cases and mechanical for 77.3%, including 120 cases of strangulation occlusion (95.2%) and 6 cases of obstruction. Etiologies were dominated by adhesions and/or fibrous bands (61.2%). Medical treatment resolved the occlusive syndrome in 9.2% of cases, instrumental treatment in 17.1% and surgical treatment in 77.3%. Adhesiolysis/section of fibrous bands (55.7%), detorsion (14.3%) and resection anastomosis (11.9%) were the most common surgical procedures. overall morbidity was 11.6%, dominated by surgical site infection (7.14%). The mean resumption of intestinal transit was 2.7 days, and the mean hospital stay was 7.9 days. overall mortality was

关键词： Intestinal obstruction Emergency Surgery Ziguinchor

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Comparative Study between dielectric Properties and Compaction Parameters: Case Study on Three Laterite Quarries

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open Journal of Geology 2024年第8期14卷 746-759页

作者： cheikh dial.o diene Sabou Sarr Abdoulaye Cissé Mapathé Ndiaye Laboratoire de Gophysique UFR Sciences de lIngnieur University Iba Der Thiam Thies Senegal Laboratoire de Modlisation et de Mcanique des Sols UFR Sciences de lIngnieur University Iba Der Thiam Thies Senegal

This work studies the variability of the relationship between relative permittivity and compaction parameters as a function of certain geotechnical properties for different laterite types. This study allows to purpose the dielectric permittivity as a third compaction parameter allowing to obtain a non destructive control méthod. Preliminary studies on diack laterite had shown a good correlation. Additional investigations are carried out to verify the possibility of generalizing this correlation to three new laterite careers: Ngoudiane, Yéba and Fandene. To proceed, particle size analysis, Atterberg limits, specific weight tests and compaction according to the modified Proctor test were performed on laterite samples. Using the radar method, experimental permittivities are determined for laterite samples by the point method of propagation times and confirmed by the diffraction hyperbole method. The geotechnical and radar data obtained allowed correlations between permittivity and water content on the one hand and between permittivity and dry density on the other. The results show that the maximum dry density as a function of permittivity corresponds with the optimum Proctor, which confirms the results previously obtained on diack laterite.

关键词： Radar Laterite Moisture Content Dry Density Permittivity Geotechnical Properties

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Fish Assemblage and Abundance distribution in Nanji Islands Marine Nature Reserve in Relation to Season Change

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Journal of Agricultural Chemistry and Environment 2024年第1期13卷 13-32页

作者： cheikh Sarr Cungen Yu ousmane Ndiaye Hamet diadhiou Ngor Ndour Laboratory of Fishery Resources Zhejiang Ocean University Zhoushan China Laboratory of Agriculture and Environmental Sciences National High School of Agriculture Thies Senegal Senegalese Institute of Agriculture Research Oceanographic Research Center of Dakar Thiaroye Dakar Senegal Laboratory of Agroforestry and Plant Production Assane Seck University of Ziguinchor Ziguinchor Senegal

The fishing survey station located in the warm waters of the East China Sea is one of the abundant fishery resources of waters;with a large number of economic fish breeding grounds and economic juvenile feeding grounds. Several fish species according to this bottom trawl survey results which appear in the annual survey from winter to autumn give us a total of 58 species, which have appeared throughout the year. But the vast majority of species appears only in certain seasons, according to the sea fish survey and based on seasonal migratory species or species mainly small endemic species. The survey of fish is tropical and subtropical warm water species and warm temperate species, and the history of the area has several types of 397 different species. There are many reasons, in addition to recent years, human disturbance and adverse consequences of environmental changes brought about, but also with the relevant sampling methods and sampler time, the survey sampled only trawl based, from Ping yang ocean and Fisheries Bureau, the waters are still other jobs method net, gill nets, fishing industry, etc. Survey results show that the type of fish in the summer (58 species) > spring (55 species) > winter (51 species) > autumn (42 species). The type of season was among spring to summer rose, summer to autumn decline. The survey found that in the reef area of the Nanji Islands, no one species of fish is the dominant species throughout the year (according to the dominant species, each species is dominant only in one season). From the dominant species turnover accounting for the four seasons, in winter it has 53.72% of the total biomass or annual biomass, spring it has 41.53% of the overall biomass, summer it has 31.85% and autumn it has 38.56% of total biomass. Visible, seasonal succession of dominant species of fish phenomenon is very obvious, especially in the spring and winter, summer transfers dominate species at this stage show the greatest change, but winter, the transf

关键词： Nanji Islands Species Composition Abundance distribution Seasons

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Influence of the Nature of the Incoming Sludge on the Performance of a Vertical Flow Reed Beds in Dakar-Senegal

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Journal of Water Resource and Protection 2024年第6期16卷 429-449页

作者： Elhadji Mamadou Sonko diomaye dieng Maïmouna Lo cheikh diop Laboratoire dEtude Environnemental des Milieux Urbains (LEEMUR) Institut des Sciences de lEnvironnement (ISE) Facult des Sciences et Technique (FST) Universit Cheikh Anta Diop de Dakar (UCAD) Dakar-Fann Sngal

This work investigates the influence of the type sludge on drainage, plant development, purification performances and biosolids quality. Drainage properties were measured through the frequency of clogging, the percentage of leachate recovered and the dryness of accumulated sludge. Plant development was measured through the density, the height and the stem diameter. Purification performance was evaluated from the reduction rate. Biosolids quality was measured after 3 months of maturation. The results show that the clogging frequencies were 9.5%;0% and 3.7%;the volume of leachate recovered was 42.2%;20.4% and 24.7% and, the dryness was 33.4%;61.1% and 52.4% for FS-ST, FS-STT and SS respectively. Plants densities were about, with densities 197.1, 171.3 and 178.3 plants/m2 in beds fed respectively with FS-ST, FS-STT and SS. Despite the high removal rates, the concentrations of pollutants in the leachates are above the Senegalese standard NS 05-061 for discharge into the environment. The biosolids are all mature with C/N and NH4+/No3?ratios lower than 12 and 1 respectively. The biosolids are also rich in organic and mineral elements. The concentrations of Ascaris eggs are higher than the WHo recommendations. These biosolids should be stored for additional time or composted.

关键词： Biosolid Quality Dewatering Performance Planted Drying Beds Purification Performance Sludge Type

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Contribution of Garcinia kola to the Productivity and Economic Profitability of the Community Agricultural Area of Kedougou: Financial and Comparative Analysis of Production Factors

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Journal of Agricultural Chemistry and Environment 2024年第1期13卷 54-66页

作者： cheikh Sarr Ngor Ndour Abdoulaye Badji ousmane Ndiaye Hamet diadhiou Laboratory of Agroforestry and Plant Production Assane Seck University of Ziguinchor Ziguinchor Senegal Enda ECoPoP/Tambacounda Regional office Tambacounda Senegal Laboratory of Agriculture and Environmental Sciences National High School of Agriculture Thies Senegal Senegalese Institute of Agriculture Research Oceanographic Research Center of Dakar Thiaroye Dakar Senegal

Inland fishing predominates in the Kedougou region, which has no coastline. This type of fishing does not yet meet the local population’s demand for fish products. In response to this concern, a Community Agricultural Estate housing an integrated fish farm was set up in the commune of Bandafassi, in the village of Itato. Since its creation, this production unit has been faced with the problem of sourcing high-quality, low-cost, monosex male oreochromis niloticus fry. In order to overcome this constraint, the present research focuses on the contribution of Garcinia kola to the productivity and economic profitability of the Itato farm. The aim of the research is to assess fish production in the experimental set-up and the production costs of tilapia in a controlled environment. The comparative study of the various production factors shows disparities only in the input factor, where scenarios 2 and 3 use additional products. These are 17-α-methytestosterone for scenario 2 and Garcinia kola for scenario 3. These products significantly interfere with fish production, with a fairly high mortality rate for scenario 2 (25% for two production cycles/ cohort2 (B5, B6, B7 and B8) treated with 17-α-methytestosterone). As for scenarios 1 and 3, mortalities are 5% with or without recourse to additional products (G. kola). In addition, average fish production for the three (03) scenarios is estimated at 28687.5 kg/2 cycles. It varies from one scenario to another, i.e. 30937.5 kg/2 cycles for scenarios 1 and 3 and 24187.5 kg/2 cycles for scenario 2. It is therefore higher in scenarios 1 and 3 than in scenario 2. This difference is due to the fairly large losses of individuals in scenario 2. Furthermore, the analysis of the profit and loss accounts for tilapia production varies from one scenario to another depending on the type of farm: 476 Franc CFA for scenario 1, 610 Franc CFA for scenario 2 and 472 Franc CFA for scenario 3 (F CFA = franc of the French Colonies of Africa). The Av

关键词： Farm Typology Economic Profitability 17-α-Methytestosterone Garcinia kola Fish Farming Tilapia

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