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Evaluation of the Level of Pollution by Heavy Metals of Market Garden Soils along the Chari River in Ndjamena: Case of the 9th and 7th Districts

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Agricultural sciences 2024年第8期15卷 939-961页

作者： Kotva Wana Mackaye Hassane Taisso Likius Andossa Béral Djétenbé Laboratoire Gosciences Dpartement des Sciences de la Terre Facult des Sciences Universit de NDjamena NDjamena Chad Laboratoire Gosciences Dpartement des Sciences de la Terre Facult des Sciences Universit de Mongo Mongo Chad Laboratoire Sol et Environnement (LASEN) Dpartement des Sciences de la Terre Facult des Sciences Universit de Ngaoundr Ngaoundr Cameroun

The main aim of this study was to characterize the metal content of soils used for market gardening along the Chari river: the 7th and 9th districts of NDjaména. To achieve this, two sites were selected: Gassi and Walia, and two control sites (Gassi and Walia). A total of fifty (50) soil samples were taken (24 from the Gassi site, 24 from the Walia site and 2 as control soils) and then analyzed to determine a number of physico-chemical parameters (pH, OM and electrical conductivity) and heavy metal concentrations in the various soils. The TME content (As, Cd, Cu, Cr, Ni, Pb, Hg and Zn) of the soils was determined by plasma-coupled Atomic Emission Spectrometry. In order to assess the level of contamination in Gassi and Walia soils, the geoaccumulation index (GeoIndex), contamination factor and degree of contamination were calculated. Results for physico-chemical parameters revealed that pH ranged from acidic (4.6) to moderately neutral (6.5), electrical conductivity was higher in cultivated soils (mean 292.14 μs/cm) than in control soils (mean 149.33 μs/cm), and soils were rich in organic matter. Overall, heavy metal concentrations in cultivated soils were higher than in control soils. The pollution estimate shows that soils in the area have no moderate contamination. The increase in TME concentrations in cultivated soils is thought to be due to the input of agricultural inputs to the soil. However, these levels are below the Average shale reference and Canadian guidelines for agricultural soil quality. Principal component analysis shows that metals are positively and significantly correlated with each other, and negatively and moderately significantly correlated with each other.

关键词： Contamination Agricultural Soils City of N’Djaména ETM Gassi Walia

Land Use and Gully Dynamics in the Kourfa Watershed, Matankari (Southwest Niger)

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Journal of Geographic Information System 2024年第4期16卷 306-320页

作者： Bachirou Hamadou Younoussa Tahirou Hassane Yaou Bouba Hassane Abass Kadade Sabou Abdoulkader Moussa Issaka Amadou Abdourhamane Toure Zibo Garba facult des sciences et Techniques Universit de Dosso Dosso Niger facult des sciences et Techniques Universit Abdou Moumouni de Niamey Niamey Niger facult des sciences et Techniques Universit Andr Salifou de Zinder Zinder Niger

The main consequences of climate change in the Sahel have been the metamorphosis of surface conditions. These metamorphoses have resulted in surface degradation, of which silting up of watersheds is the main phenomenon. The objective of this study is to assess the environmental trends of the Kourfa pond watershed. The study is based on diachronic mapping with Landsat satellite images and Google Earth images, over the period 1986 to 2021. The study reveals that vegetation (whose rate of regression doubled between 1986 and 2021) has decreased to the benefit of crop areas (whose rate of increase multiplied by 3.61 between 1986 and 2021). Bare soil and encrusted areas have also decreased, with regression rates almost double than those of 1986. In addition, the Kourfa waterholes have experienced two types of changes over 35 years: one progressive between 2011 and 2016 and the other regressive between 2001 and 2021 compared to 1986. The ravine network has been multiplied by a factor of 2.4, with density more than doubled and the connectivity of the hydrographic networks has risen from 2 to 4, with significant bank recession. This dynamic of the Kourfa pond is linked to the high drainage, the increasing complexity of the gully network and the erosion due to the retreat of the watershed banks, all of which contribute to the silting-up of the Kourfa watershed.

关键词： Kourfa Pond Dynamics Watershed Dosso Niger

Black hole shadows in Einstein-Bel-Robinson gravity

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Chinese Physics C 2024年第5期48卷 272-283页

作者： B.Hamil B.C.Lütfüoğlu Laboratoire de Physique Mathématique et Subatomique Facultédes Sciences ExactesUniversitéConstantine 1ConstantineAlgeria department of Physics University of Hradec KrálovéRokitanského 6250003 Hradec KrálovéCzechia

Gravity models given by higher-order scalar curvature corrections are believed to bear important consequences. Einstein-Bel-Robinson (EBR) gravity with quartic curvature modification motivated Sajadi et al. to explore static spherically symmetric black hole solutions using perturbative methods. In this study, inspired by their work, we investigate AdS black hole shadows in EBR gravity and demonstrate how the gravity parameter alters the energy emission rate. Finally, we address the same problem in the presence of plasma, because the black holes are thought to be surrounded by a medium that changes the geodesic of photons.

关键词： black hole shadows Einstein-Bel-Robinson gravity plasma

Experimental and numerical investigation of iron ore pellet firing using coupled CFD-deM method

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Particuology 2024年第10期93卷 75-86页

作者： Hafez Amani Eskandar Keshavarz Alamdari Mostafa Keshavarz Moraveji Bernhard Peters School of Material Engineering and Advanced Processes Amirkabir University of Technology(Tehran Polytechnic)424 Hafez AveTehran15875-4413Iran facultédes sciences de la Technologie et MédicineUniversity of LuxembourgCampus Kirchberg 6Rue Coudenhove-KalergiKirchberg L-1359Luxembourg

Iron ore pellets are the main feedstock in ironmaking processes. While extensive research has addressed numerical modeling of the iron ore pellet induration process, little effort has been made to describe the intricate thermochemical processes occurring within the reactor starting from the pellet and particularly at the intra-particle scale. In this regard, discrete-continuous methods like CFD-deM can generate more realistic, irregular particle assemblies, which leads to significantly more accurate predictions of voidage variation, wall effects, temperature distribution, and associated mass transfer phenomena. This study presents a numerical model based on computational fluid dynamics (CFD) coupled with the discrete element method (deM) to simulate the thermal induration process of iron ore pellets. The presented model solving heat, mass, and momentum conservation equations for both continuous and discrete phases, provides detailed information on the thermochemical aspects of the process. Pilot-scale induration experiment was conducted to validate model predictions in terms of thermal history and final conversion fraction. It was found that inlet charge specifications, such as particle and pellet size, significantly impact the productivity of pelletizing plants, highlighting the potential of the presented model to optimize the process and improve plant productivity.

关键词： CFD-deM Heatandmass transfer Ironorepellets Powderand pelletsize Modeling

Primary Non-Hodgkin’s Malignant Lymphoma of the Uterus at the Reference Hospital of Maradi/Niger: A Case Report

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Open Journal of Blood Diseases 2024年第2期14卷 43-46页

作者： Moustapha Elhadji-Chefou Badé Malam-Abdou Amadou Djibrilla-Almoustapha Maman Brah Moustapha Oumou Kimso Ibrahim Timi Liman Elhadji Ali Issa Abdou Amadou Borges Moreno Yuribet facult des sciences de la Sant Universit Dan Dicko Dankoulodo de Maradi Maradi Niger Hopital de Reference de Maradi Maradi Niger facult des sciences de la Sant Universit Abdou Moumouni de Niamey Niamey Niger facult des sciences de la Sant Universit Andr Salifou de Zinder Zinder Niger

Malignant non-Hodgkins lymphoma (MHNL) of the uterus is uncommon. We report a case diagnosed on the basis of histologic and immunohistochemical studies of a hysterectomy specimen induced by a very painful pelvic mass in a 50-year-old patient with no previous history of the disease. It was classified as Ann Arbor IV Bb after imaging, given the medullary infiltration and signs of clinical and biological evolutivity: the patient had received two courses of chemotherapy, CHOP protocol. She died 23 days after the second treatment due to a hypertensive crisis.

关键词： Malignant Non-Hodgkin’s Lymphoma Uterus Referral Hospital Maradi/Niger

Trends of Land Use and Land Cover Change in the Savannah Ecological of the Protected Area Reserve Partielle de Dosso, Niger

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Natural Resources 2024年第3期15卷 61-68页

作者： Amadou Issoufou Abdourhimou Moussa Boubacar Habou Rabiou Soumana Idrissa Mahamane Ali faculté des sciences Agronomiques Université de Diffa Diffa Niger Institut National de la Recherche Agronomique du Niger Niamey Niger faculté des sciences et Techniques Université Abdou Moumouni de Niamey Niamey Niger

Information on the dynamics of savannah is important to a country's plan to overcome the problems of uncontrolled development and environmental hazards. Taking the reserve partielle de Dosso, Niger as the case study area, this paper analyzed the long-term land use land cover change from 2002 to 2022. Satellite images were processed by using Google Earth Engine (GEE). Therefore, four major land cover classes were identified based on spectral characteristics of Land sat, namely, built-up, vegetation, cropland, bare land and water. The result revealed that barren and built-up areas increased at the expense of vegetation and water. From the four major land use land cover the large area is covered by vegetation which comprises about 192963.5 hectares followed by cropland and water consisting of 32506.43 and 1596.4 hectares respectively. The built-up area gained substantial area (most) during the study period. The reduction in some of the land cover/uses underlines the dangerous trend of the pressure poised by population growth and the changing functionality. Land cover change is influenced by a variety of societal factors operating on several spatial and temporal levels. The area estimates and spatial distributions of the LULC classes produced from the current study will assist local authorities, managers, and other stakeholders in decision-making and planning regarding forest land cover and uses.

关键词： Land Use/Cover Change detection Classification Dosso

Human brain computing and brain-inspired intelligence

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National Science Review 2024年第5期11卷 8-9页

作者： Jianfeng Feng Viktor Jirsa Wenlian Lu Institute of Science and Technology for Brain-Inspired Intelligence Fudan University Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence(Fudan University) Ministry of Education Shanghai Center for Mathematical sciences Fudan University department of Computer Science University of Warwick Zhangjiang Fudan International Innovation Center Institut de Neurosciences des Systèmes Faculté de Medécine

The relationship between structure, neural activity dynamics and intelligent human brain function is complex and multifaceted with deep roots in several academic disciplines. Its understanding is a fundamental goal of brain research [1] and may indicate the way towards the next generation of artificial intelligence [2]. There are major challenges on the way, several of which are addressed in this Special Topic of National Science Review.

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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

Fuzzy Henstock-Kurzweil Triple Integral on a Type 1 Quasi-Fuzzy Parallelepipedal Domain

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Journal of Applied Mathematics and Physics 2024年第3期12卷 897-911页

作者： Kumwimba Seya Didier Kasongo Ntambwe Dany Panga Lutanda Grégoire Mayuke Katshongo Jean Paul Lunda Ngoy Jean Pierre Département de Mathématiques et Informatique Faculté des Sciences Université de Lubumbashi Lubumbashi Democratic Republic of the Congo

In this article, we propose by using the Hausdorff distance Simpson’s rule for the triple integral of a fuzzy-valued function and the error bound of this method, one of the variables of which is fuzzy. In addition, thin δ-fine partitions are introduced. The integration domain is a quasi-fuzzy parallelipiped. A numerical example is presented in order to show the application and the significance of the method.

关键词： Fuzzy-Valued Function Hausdorff Distance Quasi-Fuzzy Parallelipiped Henstock Integral