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Journal of Geoscience and Environment Protection 2022年第9期10卷 136-148页

作者： Gbele Ouattara Gnammytchet Barthélémy Koffi Allou Gnanzou kouakou alphonse yao Laboratory of Civil Engineering Geosciences and Geographic Sciences National Polytechnic Institute Félix Houphou&#235 t-Boigny Ya-moussoukro Ivory Coast Laboratory of Geology Basement and Metallogeny UFR-STRM Félix Houphou&#235 t-Boigny University Abidjan Ivory Coast

Ivory Coast is a country rich in base metals and precious minerals: gold, manganese, diamond, iron, bauxite, cobalt and nickel. These natural resources are exposed to destruction and fragmentation by mining activities. The artisanal and small-scale exploitation of gold are increasingly practiced in our rural areas. These activities escape often in the control and monitoring of the mining administration. In order to better constrain these activities on the environment, the present work used remote sensing imageries to see its spatio-temporal impacts in the rural world in central Ivory Coast. The results show that gold artisanal activities have been practiced since 2013 and are experiencing an increasingly important growth. We note a devastation of forests and savannahs, a pollution of surface water, as well as an increase in poverty in rural areas. These activities are practiced near habited areas (villages). This creates a reduction of cultivatable soil. Remote sensing imageries make it possible to quickly map areas at large-scale gold mining in time and space.

关键词： Gold Panning Artisanal Mining Space and Time Remote Sensing Imageries Ivory Coast West Africa

Production of High-Purity Silica Sand from Ivorian Sedimentary Basin by Attrition without Acid Leaching Process for Windows Glass Making

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Journal of Minerals and Materials Characterization and Engineering 2021年第4期9卷 345-361页

作者： Péyokoh Roger Thio Kouassi Bruno Koffi Kouadio Denis Konan kouakou alphonse yao Mechanics and Materials Science Laboratory Yamoussoukro C&#244 te d’Ivoire National Polytechnic Institute Félix Houphouë t-Boigny (INPHB) Yamoussoukro C&#244 te d’Ivoire Civil Engineering Geoscience and Geographic Sciences Laboratory Yamoussoukro C&#244 te d’Ivoire

To produce high-purity silica sand usable for glass making, the present study was carried out. The objective of this work was to increase the silicon dioxide (SiO2) content to at least 99% using a simple process without chemical input. The raw sand samples were taken from the Ivorian sedimentary basin, from Maféré and Assinie areas, Côte d’Ivoire. Wet sieving and attrition technique were used for the purification process. The results from the energy dispersive spectrometer (EDS) analyses of the raw and treated samples show a significant increase of silica content and a significant reduction of impurities. The silica content (SiO2) of the sand of Maféré increases from 98.73% ± 0.15% to 99.92% ± 0.05%. And the sand of Assinie increased from 98.82% ± 0.67% in the raw samples to 99.44% ± 0.27% after treatment. The rate of iron oxide and alumina is reduced in these sands. Moreover, the sand of Maféré contains 53.2% of grains of size lower than 500 microns and that of Assinie contains 29.30%. Regarding the chemical composition of these purified sands, they meet the standard BS2975s, the American Ceramic Society and the National Bureau of Standards for window glass making.

关键词： Silica Sand Silicon Oxide Attrition Wet Sieving Soda Lime Glass Maféré Assinie Côte d’Ivoire

Geochemical Exploration of Sediments in the Toumodi Region: Origin of Metasediments, Geological Dynamics, and Perspectives for Regional Geological History

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Open Journal of Geology 2023年第12期13卷 1255-1270页

作者： N’dri Eudes Sati Tegan Alain Nicaise Kouamelan alphonse kouakou yao Ouattara Gbele Ziandjêdé Hervé Siagne Koffi Aléxis N’Dri Department of Civil Engineering Geosciences and Geographic Sciences INP-HB Yamoussoukro C&#244te d’Ivoire Laboratory of Geology Mineral and Energy Resources/Training and Research Unit in Earth Sciences and Mineral Resources Félix Houphou&#235t-Boigny University Abidjan Ivory Coast

The region of Toumodi, located in the heart of the West African Craton, is renowned for its geological complexity. This geochemical study delves into the origin of siliciclastic sediments and the geodynamic context of their formation. The study reveals that Toumodi’s sediments exhibit an intriguing mineralogical composition, with indications of a dual source of parent rocks, one rich in quartz and the other poor in quartz. Furthermore, geochemical analysis highlights a variation in sediment maturity from west to east, indicating the coexistence of distinct geotectonic environments in the region. In the eastern part of the Toumodi region, a passive margin is defined characterized by sediments with an abundance of quartz, while to the west, an active margin is observed with sediments having a lower quartz content. This arrangement suggests the presence of a potential suture zone in the region. This geological complexity underscores the importance of further research to better understand the origin of sediments and the processes that have shaped them. Moreover, this study sheds new light on the fascinating geology of Toumodi, but many questions remain to be explored.

关键词： Toumodi Birimian Siliciclastic Sediments Sediment Maturity

Production of High-Purity Silica Sand from Ivorian Sedimentary Basin by Attrition without Acid Leaching Process for Windows Glass Making

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Geochemical Exploration of Sediments in the Toumodi Region: Origin of Metasediments, Geological Dynamics, and Perspectives for Regional Geological History

Journal of Minerals and Materials Characterization and Engineering（矿物质和材料特性和工程） 2021年第4期

作者： Péyokoh Roger Thio Kouassi Bruno Koffi Kouadio Denis Konan kouakou alphonse yao

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Structural Stability and Accumulation of Organic Matter in Some Soils under Cashew Tree Orchards in the Department of Touba in North-West Cote d’Ivoire

Open Journal of Geology（地质学期刊） 2023年第12期

作者： N’dri Eudes Sati Tegan Alain Nicaise Kouamelan alphonse kouakou yao Ouattara Gbele Ziandjêdé Hervé Siagne Koffi Aléxis N’Dri

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Open Journal of Soil Science 2020年第5期10卷 181-193页

作者： Alui Konan alphonse Ballo Koffi Celestin Kouassi kouakou Joselin yao-Kouame Albert UFR of Biological Sciences Geosciences DepartmentPedagogical and Research Unit(UPR)of Agro-PedologyPeleforo University Gon CoulibalyKorhogoCote d’Ivoire National Center for Agronomic Research AbidjanCote d’Ivoire UFR of Earth Sciences and Mining Resources Department of Soil SciencesFelix Houphoüet-Boigny UniversityAbidjanCote d’Ivoire

Degradation of the physical quality of the soil is a common problem encountered in agrosystems, particularly in the case of open field cropping systems in the northern areas of Côte d’Ivoire. Thus, the structural stability of the soil, which is a good indicator of the sensitivity to threshing and to water erosion in relation to the accumulation of organic matter, was evaluated in two types of soil (Ferralsol and Cambisol) in cashew orchards, in two villages (Mahana and Sanankoro) producing cashew nuts, located the Department of Touba in the North West of Côte d’Ivoire. The objective of this study is to develop new technical routes that are better suited to further promote the sequestration of organic carbon in the soil. Soil samples were taken from open soil profiles at the two chosen sites to allow laboratory analyzes. The results indicate that the surface horizon of Cambisol (site 1) is more stable (Is = 0.78) than that of Ferralsol (site 2;Is = 1.08) with nevertheless relatively small thicknesses of horizons. The median horizons and those of depth, indicate a mediocre stability (Is vary from 1.03 to 1.62). In terms of the quantity of organic carbon, the estimated values vary from 1.96 to 4.53 t⋅ha−1 for Cambisol (site 1) and from 1.44 to 3.46 t⋅ha−1 for Ferralsol (site 2). These values remain relatively low especially at the level of the median horizons and those located in depths. Statistical tests have shown a very highly significant and negative association between the structural stability of soils and the amount of organic carbon in the different horizons. The relationship implies that organic carbon plays an important role in the structural stability of soil horizons under cashew tree orchards.

关键词： Structural Stability Organic Carbon Soils Cashew Cote d’Ivoire

填充型具有微孔结构的磺化聚芳醚砜/聚醚砜复合质子交换膜的制备及性能

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高等学校化学学报 2019年第5期40卷 1051-1057页

作者：朱雨昕 HARAGIRIMANA alphonse 陆瑶 BUREGEYA Ingabire Providence 宁聪李娜胡朝霞陈守文南京理工大学环境与生物工程学院南京210094

制备了基于磺化聚芳醚砜(SPAES)及聚醚砜(PES)的填充型复合质子交换膜,研究了其吸水率、尺寸变化、热-机械特性、质子电导率、甲醇透过性及稳定性等性能.通过浸入沉淀相转化法,采用磺化度分别为30%(S30),40%(S40)及50%(S50)的SPAES与PE... 详细信息

制备了基于磺化聚芳醚砜(SPAES)及聚醚砜(PES)的填充型复合质子交换膜,研究了其吸水率、尺寸变化、热-机械特性、质子电导率、甲醇透过性及稳定性等性能.通过浸入沉淀相转化法,采用磺化度分别为30%(S30),40%(S40)及50%(S50)的SPAES与PES制备了系列微孔型复合质子交换膜Sx-y(x为SPAES的磺化度,y为SPAES的质量分数);然后利用真空抽滤法在微孔中填充S50制备了相应的填充型复合质子交换膜Sx-y+F50.结果表明,由于微孔的引入及皮层结构的存在,Sx-y膜在低离子交换容量(IEC)条件下仍具有较高的电导率、优良的机械强度、优异的化学稳定性及较低的甲醇透过性.经S50填充后,Sx-y+F50膜的IEC及电导率明显提升,甲醇透过率大幅下降,但机械强度及化学稳定性未见劣化.其中S30-40+F50膜(IEC=0. 69 mmol/g)的综合性能最佳,其质子电导率在90℃水中达到50. 4 m S/cm;经140℃水处理24 h后失重率仅为8. 2%,质子电导率降低仅9%;经过芬顿试剂(3%H2O2,20 mg/L Fe SO4,80℃,1 h)处理后失重率仅为0. 66%;甲醇透过率仅为6. 8×10-8cm2/s.

关键词：燃料电池浸入沉淀相转化填充型微孔复合质子交换膜磺化聚芳醚砜聚醚砜质子电导率

Influence of Mineral Fertilization on the Capacity of Nodulation of Three Species of Legumes(Groundnut,Cowpea and Soybean)

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American Journal of Plant Sciences 2019年第12期10卷 2208-2218页

作者： Kouassi N’dri Jacob Kouame N’guessan Alui Konan alphonse yao Koffi Joel Ayolie Koutoua Yatty Kouadio Justin Laboratory of Improvement of Agricultural Production University Jean Lorougnon GUEDEAgroforestry UFRDaloaCote d’Ivoire Geosciences Department University Péléforo Gbon CoulibalyBiological SciencesUFRKorhogoCote d’Ivoire

Groundnut (Arachis hypogaea), cowpea (Vigna unguiculata) and soybean (Vigna radiata) are the main food legumes grown in Cote d’Ivoire and the localities of Haut-Sassandra. These legumes are highly valued for their nutritional, agronomic and economic value. Groundnut, cowpea and soybean are the main food legumes grown in Cote d’Ivoire and in the localities of Haut-Sassandra. On the other hand, Ivorian soils are characterized by a tendency towards acidification and a decrease in the content of nutrients such as phosphorus and nitrogen which have a direct impact on the products. To restore soil fertility, farmers use mineral fertilization. However, this fertilization has an influence on the nodulation of these legumes. The study took place at Jean Lorougnon University. We adopted a completely random experimental block device. The parameters measured included the number of nodules, the length and weight of the plant, the length and weight of the root system. Our results showed that mineral fertilization reduced the nodulation capacity of legumes. However, a small dose of phosphorus ( g) would be required for early growing legumes.

关键词： Mineral Fertilization Legumes Nodulation Phosphorus