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An Integrated Approach for Improved Permeability and Reservoir Quality Prediction in Multiporosity Systems， Tahe Ordovician Naturally Fractured Vuggy Carbonates

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Journal of Earth Science 2022年

作者： issoufou Aboubacar Mahaman Salifou Heng Zhang issoufou ousmane boukari Jie Li Cai Zhongxian Université Dan Dicko Dankoulodo de Maradi， Faculté des Sciences et Techniques， Département de Géologie Key Laboratory of Tectonics and Petroleum Resources， Ministry of Education， China University of Geosciences (Wuhan) Université Abdou Moumouni， Faculté des Sciences et Techniques， Département de Géologie

Carbonates present complex pore systems that strongly influence the physical properties and their interrelationships. This study proposes a new approach to establish pore-type mixing-based permeability transforms by integrating well-log and core data. We investigate the influence of pore-structure heterogeneity on permeability and velocity through the rock-frame flexibility factors (γ and γμ)， derivable using standard sonic and density logs. We derive permeability transforms， with correlation coefficients， R of 0.8 to 0.9， from core measurements and pore-structure variations-dependent physical parameters， namely the porosity exponent (m)， Poisson’s ratio (σ)， velocity deviation log (VDL)， and velocity ratio (VR). Through extrapolation using log-data， the m- and VDL- based correlations provide significantly better permeability estimates， with the highest accuracy attained with the m-based correlation， whereas the VR- and σ- based correlations lead to permeability overestimation for high porosities. We plotted log-derived porosity vs. permeability， obtained applying the m-based correlation， to generate consistent porosity-permeability relationships， which account for pore-structure heterogeneity， by sorting the scattering points into distinct groups/trends by considering the variations of pore-structure types and abundance of a specific porosity. For the studied oilfield， three porosity-permeability relationships are identified， with correlation coefficients approaching 0.9， thus validating the approach and supporting its application in petrophysically similar reservoirs.

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Soil Fertility Improvement by Using Crotalaria Species Combined to Organic Amendment

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Open Journal of Soil Science 2025年第1期15卷 22-42页

作者： Pane Jeanne d’Arc Coulibaly Lassané Ouédraogo Abdoulaziz Sandwidi Barkissa Fofana Fanta Blagnan Tionyélé Fayama Badiori Ouattara ousmane boukari Diallo Dpartement Gestion des Ressources Naturelles et Systmes de Production (GRN-SP) Institut de lEnvironnement et de Recherches Agricoles (INERA)/Centre National de Recherche Scientifique et Technologique (CNRST) Ouagadougou Burkina Faso Dpartement Environnement et Fort (DEF) Institut de lEnvironnement et de Recherches Agricoles (INERA)/Centre National de Recherche Scientifique et Technologique (CNRST) Ouagadougou Burkina Faso Universit de Dori Universit Thomas Sankara Ouagadougou Burkina Faso

In Burkina Faso, agricultural land degradation, including soil fertility decline, has prompted the implementation of agricultural innovations to address this challenge. Therefore, this study aimed to evaluate the contribution of four Papilionaceous ecotypes in enhancing the fertility of degraded soils. Experiments were conducted in Noumousso and Arbollé from July to December 2024, using a randomized split-plot design combining ecotypes and organic matter and/or Burkina Phosphate amendments. Amendments were applied in four treatments: T0 (control), T1 (Organic Matter), T2 (OM + Burkina Phosphate), and T3 (BP). Determined physico-chemical properties were: particle size distribution, pH, carbon (C), nitrogen (Nt), total Phosphorus (Pt), available P (P_Bray), potassium (Kt), exchangeable bases (EB), cation exchange capacity (CEC), and saturation rate (SR). The evaluated agronomic parameter was total biomass. Results revealed that the soils at both sites were characterized by acidic sandy-clay texture and low levels of C, N, P, K, EB, and CEC. Cultivating papilionaceous and applying organo-mineral amendments contributed to increased levels of C, available P, and Mg2+, as well as improved SR. Acidity decreased at Arbollé, while showing a slight increase at Noumousso. Interaction between the two factors helped reduce acidity at both sites and significantly increased C, N, and available P contents. The organo-mineral amendment also enhanced biomass production across all ecotypes. At Noumousso, compared to T0, OM, OM + BP, and BP treatments resulted in biomass increases of 64.8%, 73.1%, and 38.6%, respectively. At Arbollé, the corresponding increases were 33.5%, 47%, and 23.4%. On both sites, OM + BP amendment had the greatest impact on improving biomass production, followed by organic amendment. These findings are of great importance to farmers for restoring the fertility of degraded soils. Therefore, the use of leguminous species in combination with organic matter enriched

关键词： Agricultural Innovations Burkina Phosphate Herbaceous Papilionaceous Organic Matter

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Design of Dipoles for the RF Energy Harvesting System Dedicated to GSM Applications

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Energy and Power Engineering 2025年第1期17卷 1-12页

作者： Abdoul Karim Mbodji Mohamed El Moctar Malang Kambaye ousmane Dieme Department of Physics Applied of UFR-SAT University Gaston Berger Saint-Louis Senegal

Nowadays, we are witnessing an era marked by the autonomy of wireless devices and sensor networks without the aid of batteries. RF energy harvesting therefore becomes a promising alternative for battery dependence. This work presents the design of an RF energy harvesting system consisting mainly of a rectenna (antenna and rectification circuit) and an adaptation circuit. First of all, we designed two dipole type antennas. One operates in the GSM 900 MHz band and the other in the GSM 1800 MHz band. The performances of the proposed antennas are provided by the ANSYS HFSS software. Secondly, we proposed two rectification circuits in order to obtain conversion efficiencies at 0 dBm of 64% for the system operating at the frequency of 900 MHz and 37% for the system at the frequency of 1800 MHz RF-DC. The rectifiers used are based on Schottky diodes. For maximum transfer of power between the antenna and the rectification circuit, L-type matching circuits have been proposed. This rectifier offers DC voltage values of 806 mV for the circuit at the frequency of 900 MHz and 616 mV for the circuit at the frequency of 1800 MHz. The adaptation circuits are obtained by carrying out simulations on the ADS (Advanced Design System) software.

关键词： Rectenna Antenna RF-DC Conversion Schottky Diode Efficiency RF Energy Harvesting

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On the Occurrence of Different Classes of Solar Flares during the Solar Cycles 23 and 24

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Journal of High Energy Physics, Gravitation and Cosmology 2025年第1期11卷 28-38页

作者： Longo Wilfried Sanon Wendpuiré ousmane Compaoré Somaïla Koala Jean Louis Zerbo Laboratoire de Matriaux dHliophysique et Environnement (La.M.H.E) Universit Nazi BONI Bobo-Dioulasso Burkina Faso Institut Universitaire de Technologie (IUT) Universit Nazi BONI Bobo-Dioulasso Burkina Faso Unit de Formation et de Recherche en Sciences Exactes et Appliques (UFR/SEA) Universit Nazi BONI Bobo-Dioulasso Burkina Faso

In this study we review the occurrence of different types (A, B, C, M, and X classes) of solar flares during different solar cycle phases from 1996 to 2019 covering the solar cycles 23 and 24. During this period, a total of 19,126 solar flares were observed regardless the class: 3548 flares in solar cycle 23 (SC23) and 15,668 flares in solar cycle 24 (SC24). Our findings show that the cycle 23 has observed the highest occurrences of M-class and X-class flares, whereas cycle 24 has pointed out a predominance of B-class and C-class flares throughout its different phases. The results indicate that the cycle 23 was magnetically more intense than cycle 24, leading to more powerful solar flares and more frequent geomagnetic storms, capable of generating significant electromagnetic emissions that can affect satellites and GPS signals. The decrease in intense solar flares during cycle 24 compared to cycle 23 reflects an evolution in solar activity patterns over time.

关键词： Solar Flare Solar Cycle Solar Cycle Phase Solar Flare Class Occurrence

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Design and Optimization of Terracotta Tube-Based Direct Evaporative Cooling Exchanger: An Analytical Approach to Heat and Mass Transfer

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Open Journal of Applied Sciences 2025年第1期15卷 352-373页

作者： Windnigda Zoungrana Makinta Boukar ousmane Coulibaly Guy Christian Tubreoumya Antoine Bere Laboratoire dEnergtique dElectronique dElectrotechnique dAutomatique et dinformatique Industrielle Universit Abdou Moumouni Niamey Niger Laboratoire de Physique et de Chimie de lEnvironnement Universit Joseph Ki Zerbo Ouagadougou Burkina Faso

This study develops an analytical model to evaluate the cooling performance of a porous terracotta tubular direct evaporative heat and mass exchanger. By combining energy and mass balance equations with heat and mass transfer coefficients and air psychrometric correlations, the model provides insights into the impact of design and operational parameters on the exchanger cooling performance. Validated against an established numerical model, it accurately simulates cooling behavior with a Root Mean Square Deviation of 0.43 - 1.18˚C under varying inlet air conditions. The results show that tube geometry, including equivalent diameter, flatness ratio, and length significantly influences cooling outcomes. Smaller diameters enhance wet-bulb effectiveness but reduce cooling capacity, while increased flatness and length improve both. For example, extending the flatness ratio of a 15 mm diameter, 0.6 m long tube from 1 (circular) to 4 raises the exchange surface area from 0.028 to 0.037 m2, increasing wet-bulb effectiveness from 60% to 71%. Recommended diameters range from 5 mm for tubes under 0.5 m to 1 cm for tubes 0.5 to 1 m in length. Optimal air velocities depend on tube length: 1 m/s for tubes under 0.8 m, 1.5 m/s for lengths of 0.8 to 1.2 m, and up to 2 m/s for longer tubes. This model offers a practical alternative to complex numerical and CFD methods, with potential applications in cooling tower optimization for thermal and nuclear power plants and geothermal heat exchangers.

关键词： Analytical Modeling Porous Terracotta Tube Direct Evaporative Cooling Heat and Mass Exchanger Performance Optimization

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Human Effects on Tabounsou’s Coastal Ecosystem and the Matoto-Conakry Case Study of Sustainable Management Practices

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Journal of Environmental Science and Engineering(A) 2025年第1期14卷 43-52页

作者： Daouda Konate Ahmed Guisse Yamoussa Bangoura ousmane II Camara Sekou Ahmed Bangoura Department of Fisheries and Aquaculture Higher Institute of Veterinary Sciences and Medicine of DalabaBP09 Dalaba+224Guinea Conakry RogbanèScientific Research Center BP:1516Conakry+224Republic of Guinea Boussoura National Center for Fisheries Sciences BP1515 Conakry+224Guinea

Humans have always engaged with their surroundings and the ecology in which they ***,during the industrial age,this contact has been more intense and has had a substantial impact on environment and *** example,overexploitation of natural resources,mining,pollution,and deforestation are all elements that negatively affect biodiversity and natural *** studies have been conducted to evaluate the damage caused,despite the significant uncontrolled pressure from human ***,maintaining its environment is essential to the survival of coastal ***:This study’s goal was to evaluate how human activity affected Tabounsou’s coastal ecology in order to suggest remedial actions for sustainable *** following was the methodological approach used:executive consultation and archival analysis;stakeholder survey(locals,farmers,salt producers,fishers,and loggers);inventory of species;anthropogenic activity inventory;evaluation of how human activity affects aquatic life in the research region;suggestion and action for sustainable management;Outcome:Executive consultation indicated that the main issues are:construction projects that reduce the estuary’s surface area;agricultural practices such as woodcutting and salt farming;the rise in resource exploitation;noncompliance with fisheries laws;and the catching of young ***-three percent of fisherman ditch their nets on the coast after using them,but only seventeen percent burn *** a 75%frequency rate,the same survey indicates that most fisherman fish around the *** the Tabounsou area,according to loggers’survey,68%of the wood cut is Rhizophora,24%is Avicennia,and 8%is *** fish stocks,representing nine families and nine species,were identified by the species *** 18%and 15%,respectively,the actors most frequently capture the species Pseudotolithus elongatus and Arius *** to a poll of 30 farmers,90%of them apply fertilizer to the

关键词： Coastal environment mitigation measures sustainable management.

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Effect of Coal Fly Ash Incorporation on the Physical and Mechanical Properties of Terracotta Bricks Based on Grey Clay

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Journal of Materials Science and Chemical Engineering 2025年第1期13卷 7-19页

作者： El Hadji Moussa Diop Alpha ousmane Toure Kalidou Ba Mamadou Faye Falilou Mbacke Sambe Laboratory of Water Energy Environment and Industrial Processes (L3EPI) Ecole Suprieure Polytechnique/Cheikh Anta Diop University Dakar Senegal School of Industrial and Biological Engineering (ESGIB) Dakar Senegal

This study was part of the framework that contributed not only to the improvement of thermal comfort in housing but also to the decarbonization of the construction and building materials industry. For this purpose, terracotta brick seems to meet these needs. Thus, the objective of this work was to evaluate the influence of the incorporation of coal fly ash from a thermal power plant on the physical and mechanical properties of fired bricks from grey clay in the Thicky area of Senegal. The coal fly ash was incorporated into the raw clay material in proportions of 0, 5, 10, and 15 % by weight. These two raw materials were first characterized by X-ray fluorescence spectroscopy (XRF). The XRF analyses showed that the most abundant oxides in clay were SiO2 (55.034%) and Fe2O3 (10.155%). In coal fly ash, SiO2 (38.574%) is predominant. The ash also contained Al2O3 (7.717%) and alicano-earthy melting oxides such as CaO (9.271%) and MgO (7.298%) etc. These melting oxides were necessary to facilitate the formation of the liquid phase when baking platelets. The latter, when burned at a temperature of 880°C, were characterized by determining the number of physico-mechanical parameters, such as linear shrinkage during cooking, water absorption, fire loss and compressive strength. A Hierarchical Ascending Classification of these different parameters was performed and three classes were obtained. Class 1 with better compressive strength (6.358 MPa), was in sample A (5%). Class 2 consisted of sample D (reference) and had a higher plasticity index (28.51%) and water absorption rate (11.19%). Finally, class 3, which included samples B (10%) and C (15%), had very high shrinkage and fire losses compared to other platelets. These results highlighted the possibility of using up to 5% of the coal fly ash in the production of new fired bricks with good performance.

关键词： Grey Clay Coal Fly Ash Terracotta Bricks Construction Greenhouse Gases

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On-Station Bioefficacy of Neem Seed Extract and Beauveria bassiana 115 for Managing Major Insect Pests of Cowpea in the Sahelian Region of Maradi, Niger

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Agricultural Sciences 2025年第1期16卷 1-12页

作者： Laouali Amadou Souleymane Laminou Ousseina Abdoulaye Mahaman Nassirou Oumarou Roufai Yarifou Nana Hadiza Issa Labo Ramatou Bargui Abdoulaye Ibrahim boukari Baoua Entomologie Laboratory II Institut National de la Recherche Agronomique du Niger Maradi Niger Centre Rgional de la Recherche Agronomique de Tahoua CERRA Tahoua Niger Faculty of Agronomy Universit Dan Dicko Dan Koulodo de Maradi Maradi Niger Facult des Sciences Agronomiques Universit Boubacar B de Tillabry Tillabry Niger

Cowpea, Vigna unguiculata L. Walp, is an important food grain legume in Niger facing production losses due to insect pests. This study aims to determine the efficiency of non-chemical methods for managing these pests. A trial was conducted during the 2020 and 2022 cropping seasons at the INRAN station in the Maradi region. A Fischer experimental design with 6 repetitions was used to compare 4 treatments: synthetic chemical pesticide;the entomopathogenic fungus Beauveria bassiana;aqueous extracts of neem seeds, and control. Observations were carried out every three days. The cowpea pod-sucking bug, pod borer, and thrips were the main insect pests recorded. In terms of effectiveness, the synthetic pesticide was the best treatment. It reduced insect pest densities by 71.35% to 90.40% in 2020 and by 35.11% to 42.13% in 2022. Grain yields varied between treatments. Neem seed extract followed the synthetic pesticide and significantly reduced insect infestations in both years. The synthetic pesticide and neem seed extract resulted in yields 3 to 5 times higher than the control treatment in 2020. By contrast, B. bassiana 115 and neem seed extract produced similar yields in 2022. Therefore, the results of this study showed that B. bassiana 115 and neem seed extract have insecticidal potential and could be used as an ecological alternative for managing cowpea insect pests in the Sahel.

关键词： Vigna unguiculata Biopesticide Cowpea Insect Pest Niger

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Multi-Criteria Analysis Using Remote Sensing and GIS: Insight into Groundwater Potential of the Fissured Aquifers in the Liptako Socle (Southwestern Niger)

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Journal of Water Resource and Protection 2021年第11期13卷 881-899页

作者： Maman Sani Abdou Babaye Karimou Dia Hantchi Ibrahim Wagani boukari issoufou ousmane issoufou Sandao Department of Geology UMR SERMUG Faculty of Science and Techniques Dan Dicko Dankoulodo University Maradi Niger Department of Geology Faculty of Science and Techniques Abdou Moumouni University Niamey Niger

In the basement of southwestern Niger, weathering and fractured zones concentrate most of the groundwater. This study focuses on fractured media and aims to identify areas of productivity in this aquifer to improve the region’s water coverage. The cartographic approach developed made it possible to establish synthetic maps based on multi-criteria analysis. The hydrogeological parameters selected include fracturing data, drainage system, slope and piezometric level as well as shallow and deep lithology. The choice of these criteria is based on their physical meaning but also on the availability of data. The integration of all the criteria in a GIS allowed to generate maps of recharge and potential productivity of fractured aquifers in the area. The validation of these thematic maps with independent data confirms their utility as reference standards for accessibility for future resource exploitation. Like any spatialization tool, potential recharge maps will provide valuable information about areas where infiltration is more important, and help control and manage risk zoning. The upward evacuation effect is even more prominent along the lineaments, faults or fractures: thus, to avoid possible pollution and to locate the future hydraulic structures, the analysis of the potential recharge zones remains necessary. The potential productivity index map, in addition to the very punctual sites identified by the fracturing study, made it possible to define areas of high potential productivity.

关键词： Multi-Criteria Analysis Fissured Aquifers Productivity Groundwater Potential Niger

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Diagnosis and Management of Pediatric Brain Tumors in Togo

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Open Journal of Modern Neurosurgery 2025年第1期15卷 56-64页

作者： Agbéko Komlan Doléagbénou Ablavi Oyénitwa Solange Adani-Ifè Ben ousmane Djoubairou Ama Paula Adjidjonou Essossinam Kpélao Facult des Sciences de la Sant University of Lom Lom Togo Neurosurgery Unit Regional Hospital Center of Lom Commune Lom Togo Neurosurgery Unit Sylvanus Olympio Teaching Hospital Lom Togo Medical Oncology Unit Sylvanus Olympio Teaching Hospital Lom Togo Neurosurgery Unit Military Hospital of Yaound Yaound Cameroon

Background: Pediatric brain tumors (PBT) are among the most common childhood neoplasms worldwide, but their management in low- and middle-income countries (LMICs) remains under-documented. Limited access to specialized care, diagnostic tools, and adjuvant therapies poses significant challenges in sub-Saharan Africa, including Togo. Objective: This study reviews the management of pediatric brain tumors in Togo. Methods: We conducted a retrospective study in the neurosurgery department at Sylvanus Olympio Teaching Hospital between November 2017 and December 2022. Demographic, clinical, radiographic, operative, pathology, and outcome data were collected and analyzed. Results: Eighteen patients had histologically verified brain tumors. Ages ranged from 1 to 15 years (mean: 7.73 ± 4.28), with a sex ratio of 1. Symptoms of raised intracranial pressure were present in 83.4% of cases. The mean interval to presentation was 22 ± 5.32 months. Tumors were supratentorial in 66.7% of cases. Total tumor removal was achieved in 61.1%. Astrocytoma was the most common histological diagnosis, followed by ependymoma and medulloblastoma. Five patients (27.8%) died within the first month post-surgery. The estimated 5-year survival rate was 43% ± 5.4%. Conclusion: Delayed diagnosis, insufficient infrastructure, and limited access to radiotherapy and chemotherapy contribute to poor outcomes. Improving neurosurgical capacity, infrastructure, and financial support could enhance survival and outcomes for pediatric brain tumor patients in Togo.

关键词： Pediatric Brain Tumors Togo Neurosurgery Sub-Saharan Africa

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