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Selection of appropriate organic additives for enhancing Zn and Cd phytoextraction by hyperaccumulators

Journal of Environmental Sciences 2006年第6期18卷 1113-1118页

作者： WU Qi-tang DENG Jin-chuan LONG Xin-xian MOREL Jean-louis SCHWARTZ Christophe College of Natural Resource and Environment South China Agricultural University Guangzhou 510642 China laboratoire sol et Environnement ENSAIA-INRA 54505 Vandoeuvre-les-Nancy France

Chelant-enhanced phytoextraction is one of the most promising technologies to remove heavy metals from soil. The key of the technology is to choose suitable additives in combination with a suitable plant. In the present study, laboratory batch experiment of metal solubilization, cress seeds germination were undertaken to investigate the metal-mobilizing capability and the phytotoxicity of organic additives, including ethylene diamine triacetic acid （EDTA）, citric acid, acetic acid, oxalic acid, glutamine and monosodium glutamate waste liquid （MGWL） from food industry. Experiments in pots were carried out to study the effects of the additives on Zn and Cd phytoextraction. Furthermore, a leaching experiment with lysimeter was performed to evaluate the environmental risks of additive-induced leaching to underground water. The results showed that EDTA had a strong mobilizing ability for Zn and Cd, followed by mixed reagent （MR） and MGWL. MGWL and acetic acid at 5 mmol equivalent per liter resulted in seed germination index less than 2%. Experiments in pots verified the phytotoxicity of acetic acid and MGWL. Addition of the mixed reagent at 6--10 mmol/kg significantly increased Zn phytoextraction by Thlaspi caerulescens. The same for EDTA and the mixed reagent at 10 mmol/kg by Sedum dfredii. But only mixed reagents could significantly increase Cd phytoextraction by the studied hyperaccumulators. This suggested that the strong chelant was not always the good agent to enhance phytoextraction. S. alfredii combined with 2--10 mmol/kg soil MR was preferred for phytoremediation of Cd/Zn contaminated soils in southern China, this could result in high phytoextraction of Cd/Zn and reduce the leaching risk to underground water than EDTA assisted phytoextration.

关键词： enhanced phytoextraction heavy metals Thlaspi caerulescens Sedum alfredii EDTA organic acids mixed reagent leaching risk

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Influence of a Mineral Filler on the Fire Behaviour and Mechanical Properties of a Wood Waste Composite Material Stabilized with Expanded Polystyrene

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Open Journal of Applied Sciences 2020年第12期10卷 834-843页

作者： Koffi Clément Kouadio Brahiman Traoré Serge Pacome Kaho Conand Honoré Kouakou Edjikémé Emeruwa laboratoire du sol de l’eau et de Géomatériaux (UFR-STRM) Université Felix Houphouet-Boigny Abidjan Cote d’Ivoire

The use of vegetable fibers composites in structures sometimes presents significant fires risks because of their high flammability. This work aims to study the impact of the addition of mineral filler (clay) on the fire behaviour of wood-polystyrene composites and their mechanical properties. Thus, composites containing 25% of expanded polystyrene binder have been produced. On this base material, proportions of clay ranging from 0% to 15% were gradually added. These samples were elaborated by compaction and for some them, submitted to thermoforming after drying. Both kinds of sample were subjected to flame persistence test;flexural strength and compressive strength test were also measured. The results show that composites without mineral filler ignite continuously until the total consumption and when the mineral filler content increases the combustion time decreases. The addition of the mineral filler allows these composites to pass from class M3 of moderately flammable combustible materials to class M2 of hardly flammable materials, according to the M classification of construction and furnishing materials. The measurement of the mechanical properties shows that the strengths increase when the filler content goes from 0% to 10% and then decrease. This leads to set the optimum content of mineral filler around 10%.

关键词： Composite Expanded Polystyrene Flame Test Flammability Mechanical Properties

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Influence of the Granular Class of Crushed Granites on the Litho-Stabilization of Samo Laterites (South-East of Côte d’Ivoire)

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Open Journal of Civil Engineering 2023年第3期13卷 540-553页

作者： Abalé Martial Grehoa Conand Honoré Kouakou Koffi Clément Kouadio Souleymane Ouattara Aka Alexandre Assande Edjikémé Emeruwa laboratoire des Eaux du Sol et des Géomatériaux UFR-STRM University Félix Houphou&#235t Boigny Abidjan C&#244te d’Ivoire

Most of the laterites found in Ivory Coast do not meet the technical conditions to be used in their natural state for the design of road foundations. Also, to meet the growing needs for road materials, various amendments are made to them, including litho-stabilization. Thus, this study proposes to understand the influence of the granular class of natural aggregates on the performance of laterites. To achieve this objective, different proportions of crushed granites of class 0/5, 0/15 and 5/15 have been incorporated into the soils of southern Côte d’Ivoire, especially in Samo. This modified soil has been subjected to mechanical tests such as the modified Proctor and CBR test. The results obtained show that the dry densities of the incorporated laterites containing crushed granites increase with the content of natural aggregates and decrease with the increase in the water content. Likewise, the CBR bearing indices at 95% of the Modified Optimum Proctor of the different compositions (laterites + crushed granites) increase with the proportion of aggregates. The addition of coarse aggregates to the laterites therefore promotes the establishment of a framework which improves its bearing capacity. From 20% to 30% crushed granites respectively of class 0/15;0/5 and 5/15, the values of the CBR obtained are greater than those of 30% therefore these modified soils can be used as a foundation layer for traffic of T1, T2 and T3 type. Likewise, the laterites’ mixtures with at least 40% crushed granites of class 0/15 and 0/5 can also be used for the foundation and base layers.

关键词： Laterite Litho-Stabilization Natural Aggregate Coarse Aggregate CBR Modified Proctor Incorporated Laterites

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Preparation and Characterization of sol-Gel Derived Au Nanoparticle Dispersed Y_2O_3∶Eu Films

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Journal of Rare Earths 2005年第5期23卷 600-606页

作者：郭海张慰萍董宁楼立人尹民 Tillement O Mugnier J Bernstein E Brevet P F Structure Research Laboratory University of Science and Technology of China Academia Sinica Hefei 230026 China Department of Physics University of Science and Technology of China Hefei 230026 China Department of Physics University of Science and Technology of China Hefei 230026 China laboratoire de Physico-Chimie des Materiaux Luminescents CNRS-UMR 5620 Universite Claude Bernard Lyon I 43 Boulevard du 11 Novembre 1918 69622 Villeurbanne Cedex France laboratoire de Spectrometrie Ionieque et Moleculaire CNRS-UMR 5579 Universite Claude Bernard Lyon I 43 Boulevard du 11 Novembre 1918 69622 Villeurbanne Cedex France Department de Physique des Materiaux CNRS-UMR 5586 Universite Claude Bernard Lyon I 43 Boulevard du 11 Novembre 1918 69622 Villeurbanne Cedex France laboratoire de Spectrometrie Ionieque et Moleculaire CNRS-UMR 5579 Universite Claude Bernard Lyon I 43 Boulevard du 11 Novembre 1918 69622 Villeurbanne Cedex France)

Gold nanoparticles dispersed Y2O3 films were prepared through a sol-gel method by using yttrium acetate and Au nanoparticles colloid as precursors. The films were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM） and UV-VIS absorption spectra. XRD patterns and TEM images of Y2O3 ＋ Au films give the same resuits on structure and particle size as that of pure Y2O3 films. The surface plasma resonance （SPR） of Au nanoparticles in Y2O3 ＋ Au film was observed around 550 nm in the absorption spectrum and its position shifts to red with increasing annealing temperature is caused by the increase of dielectric constant of Y2O3 matrix and the size of Au nanoparticles. The second and third order nonlinear optical effects of Y2O3 ＋ Au films were also observed. The photoluminescent properties of Y2O3 ： Eu ＋ Au films were investigated and results indicate that there exist an energy transfer from Eu^3 ＋ to Au nanoparticles and this energy transfer decreases the emission of Eu^3 ＋ in Y2O3 ： Eu ＋ Au film.

关键词： sol-gel Y2O3 + Au films nanocomposite photoluminescence rare earths

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Predictive Study of Trace Metal Pollution of Gold Panning Sites in Birimian Formations: Case of the Yaouré Furrow (Côte d’Ivoire)

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Open Journal of Applied Sciences 2024年第7期14卷 1691-1714页

作者： Tonga Paul Tiemoko Gbele Ouattara Kouassi Ernest Ahoussi laboratoire des Sciences Gographiques du Gnie Civil et des Gosciences Institut National Polytechnique Flix Houphout-Boigny (INP-HB) Yamoussoukro Cte dIvoire laboratoiredes Sciences du sol delEauetdes Gomatriaux Universit Flix Houphout-Boigny (UFHB) Abidjan-Cocody Cte dIvoire

The present study was carried out on small-scale gold mining sites in the Yaouré region of Côte d’Ivoire. This region is geologically representative of the Birimian formations (2.1 Ga) of West Africa. The aim is to determine the potentially toxic trace metals (TMEs) generated by these sites, with a view to preventing possible contamination and/or metal pollution of the waters that provide fish products for local populations. To this end, a sampling campaign was carried out, resulting in the collection of 20 mining waste samples analyzed by X-ray fluorescence spectrometry (XRF) and 10 by X-ray diffractometer (XRD). The XRF analysis detected 06 predominant TMEs: arsenic, chromium, copper, nickel, zinc and vanadium. Statistical analysis was carried out to determine the distributions and correlations between these ETMs. To assess contamination and/or pollution levels, the following indices were calculated on the basis of reference concentrations of upper continental crust MTEs: Enrichment Factor, Geo-accumulation Index, Concentration Factor, Degree of contamination and those related to ecological risks. The results of statistical analyses and indices have shown that arsenic and chromium are the most predominant and can be, depending on the chemical form, potentially more toxic. The results of the DRX analysis show the occurrence of several minerals carrying these two MTEs, especially that of a rare mineral, Stenhuggarite, an arsenic oxide linked to hydrothermal veins. The majority of gold mining operations in West Africa are located in the birimian zone, hence the need for environmental monitoring by the relevant authorities, to prevent potential ecological risks to water and possibly health risks via the food chain.

关键词： Small-Scale Mining Metallic Trace Elements Mining Discharges Contamination Pollution Contamination Pollution Index

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Combined Effects of Compost,Supraxone and Lambda-Super on Soil Microbial Activity under Pluvial Cultivation of Sesame(Sesamum indicum L.)in Burkina Faso

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Journal of Geoscience and Environment Protection 2019年第1期7卷 107-117页

作者： Paul W.Savadogo Yacouba Zi Abdoul K.Sanou Hassan B.Nacro Francois Lompo Et Michel P.Sedogo laboratoire sol-Eau-plante Institut de l’Environnement et de Recherches Agricoles(INERA)OuagadougouBurkina Faso Institut du Développement Rural Laboratoire d’Etude et de Recherche sur la Fertilité des Sols(LERF)Université Nazi BoniBobo-DioulassoBurkina Faso

Sesame cultivation is strategic for the economy of Burkina Faso. Indeed, after cotton, sesame is the second most important agricultural product for exportation. However, its production is limited by plant diseases and pest attacks. Facing this situation, large amounts of pesticides are used to boost productivity. But, these chemicals have a negative impact on soil fertility. In this instance, the effects of Supraxone and Lambda-super in the presence of compost on soil microbial activity under rainfed sesame cultivation in a peasant environment were studied. The experiment design was a block of Fisher (BCR) comparing the non-treated parcel (TNT) to the parcel amended only with compost (C) and to the parcel amended with compost and treated with the pesticides (C + P), respectively. Soil samples were taken at depths of 0 - 20 cm before sowing at 41st and 81st days after sowing. Respiratory activity and soil microbial biomass were monitored respectively by respirometric tests and by the fumigation-incubation method. The results show that the addition of compost into the soil with or without supraxone treatment and Lambda-super resulted in an increase in microbial biomass and soil respiratory quotient. These results show that the provision of compost in sufficient quantity corrects the inhibitory effect of soil biological activity by pesticides.

关键词： Supraxone Lambda-Super Sesamum indicum L. Burkina Faso Respiratory Quotient Microbial Biomass

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Mechanical Characteristics Test of Concrete Steel Bars Available in Côte d’Ivoire

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Journal of Materials Science and Chemical Engineering 2020年第9期8卷 1-13页

作者： Conand Honoré Kouakou Ibrahima Bakayoko Mamery Adama Serifou Edjikémé Emeruwa Université Félix Houphouë t-Boigny UFR des Sciences de la Terre et des Ressources Minières Laboratoire des Sciences du sol de l’eau et de Géomatériaux Abidjan C&#244 te d’Ivoire

Buildings collapse has now become a recurrent phenomenon in Côte d’Ivoire. Therefore, this study was conducted to find out the reasons for these disasters, and check in particular to the extent, and concrete steel bars produced in Côte d’Ivoire and used in buildings’ structures are involved. Samples having 6, 8, 10 and 12 mm in diameter steel taken from the five (5) major manufacturers or suppliers of the Ivorian market were subjected to physical, chemical and mechanical tests to determine their performance. A comparison of these results with the NF EN 10080 and NF A35 080-1 standards made it possible to calculate the probability to have out-of-standard products in a structure. Pieces having 60 cm were cut from three bars of the same thickness and then subjected to tests. These are the chemical test by optical emission spectrometer, physical tests by caliper measurements of diameter, height of bolts and ribs and calculation of linear mass, and tensile tests with the help of hydraulic press. These tests made it possible to determine the characteristics of the steel bars. Then, these characteristics were compared with standards NF EN 10080 and NF A35 080-1, in order to judge their conformity for construction. Finally, the likelihood of having non-standard steel bars in a structure is calculated. These tests indicate that the relative surfaces of the bolts of the various bars HA6, HA8, HA10 and HA12 vary from 0.146 to 0.323 respectively;0.120 to 0.312;0.101 to 0, 297 and 0.142 to 0.482. Likewise, their calculated linear masses of these bars are respectively between 28.3 mm2 and 222 g/m;50.3 mm2 and 395 g/m;78.5 mm2 and 617 g/m;and 113 mm2 and 888 g/m. In addition, their yield strengths and elongations at break vary from 344 MPa to 582 MPa and from 0.2% to 15% respectively. According to analysis of these results, 100% of steel bars woul

关键词： Building Collapse Steel Bars Standards Adhesion Mechanical Performance

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Carbon and Nitrogen Mineralisation of a Lixisol in South Sudan Zone of Burkina Faso

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Agricultural Sciences 2023年第11期14卷 1547-1560页

作者： Abdramane Sanon Alain P. K. Gomgnimbou Kalifa Coulibaly Fidele K. Zongo Tièro-Wè Chris Julius Dabire Wilfiried Sanou Hassan B. Nacro Centre National de la Recherche Scientifique et Technologique (CNRST) Institut de l’Environnement et de Recherche Agricole (INERA) Laboratoire Sol-Eau-Plante (SEP) Station de Farako-Ba Bobo-Dioulasso Burkina Faso laboratoire d’étude et de recherche sur la fertilité du sol (LERF) Institut du Développement Rural (IDR) Université Nazi Boni Bobo-Dioulasso Burkina Faso Centre universitaire de Tenkodogo Université Thomas Sankara Ouagadougou Burkina Faso Unité de Formation et de Recherches en Sciences de la Vie et de laTerre Université Joseph KI-Zerbo Ouagadougou Burkina Faso

In today’s environment where agriculture needs to produce sustainably, local fertilizer resources must be encouraged to achieve multiple crop performance and environmental goals. The purpose of this study was to investigate the effects of combined inputs of biowaste and inorganic fertilisers on the mineralization of carbon and nitrogen of a Lixisol under continuous upland rice growing conditions. To this end, agronomic trials were set up in 2018 and 2019, using a Fisher randomized complete block design with 6 treatments and four replications at Farako-ba research station. The treatments were: T1 (Control), T2 (NPK + Urea), T3 (7500 kgha of Chicken droppings);T4 (7500 kg/ha of chicken droppings + 100 kg/ha of urea);T5 (7500 kg/ha of chicken droppings + 500 kg/ha of Burkina Phosphate);T6 (7500 kg/ha of chicken droppings + 500 kg/ha of Burkina Phosphate + 100 kg/ha of urea). Highest respirometry was observed in treatments T3, T4 and T6 and treatment T4 significantly increased the mineralization coefficient by 15% after 21 days of incubation. T4 and T6 resulted in increases in ammonium ion of 74.15% and 100%, respectively, compared to the control. Likewise, treatments T4 and T6 resulted in a significant increase in nitrate ion of 104.83 and 103.25%, respectively. Biowaste combined with inorganic fertilizers may have a capacity to improve the availability of leachate nutrients under upland rice conditions.

关键词： Bio-Waste Rice Carbone Nitrogen and Mineralisation

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Distribution and Characterization of Heavy Metal and Pollution Indices in Landfill Soil for Its Rehabilitation by Phytoremediation

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Journal of Geoscience and Environment Protection 2022年第1期10卷 151-172页

作者： Kraidy N’gattah Barthélémy Armel Bolou Bi Bolou Emile Allou Kouassi Daniel Université Félix Houphouë t-Boigny Unité de Formation et Recherche des Sciences de la Terre et des Ressources Minières Laboratoire des Sciences du Sol de l’Eau et des Géomatériaux (LSSEG) Abidjan C&#244 te d’Ivoire

Population growth associated with urban development in African cities is a key environmental concern in development programs. Indeed, urban areas are strongly impacted by the production of municipal waste, the management of which remains problematic and is only stored in open dumps. This is the case in the city of Bonoua, a small town located 59 km east of Abidjan in the South Comoé region of Côte d’Ivoire. The management of municipal waste in this town is crucial because all the mineral water sources are concentrated in this town. The objective of this study is to characterize and map the distribution of trace metal elements in the largest urban landfill in the city in order to propose an efficient strategy for rehabilitation into an urban park. Soil samples were collected from the entire site (landfill and surrounding soil) and from a control site. The total content of trace metals (Pb, Cd, Cr, and Zn) in the soil was analyzed by X-ray fluorescence spectrometry (XRF). Soil pollution was evaluated through enrichment factors, geoaccumulation indices and pollution indices. The results show that the calculated geoaccumulation indices and their distribution maps indicate a pollution of the site in these elements. The values of the PI higher than the unit reveal a pollution of the site in several elements. The levels of Pb, Cd, Cr and Zn are higher than the levels in the upper continental crust and in the control soil. The spatial distribution shows a significant accumulation of Pb, Cr and Zn on the landfill while Cd is concentrated in the surrounding soils. The calculated enrichment factors suggest an anthropogenic origin of the heavy metal at the study site. These results indicate polymetallic pollution by metals that can persist in the environment and affect human health.

关键词： Municipal Landfill Soil Heavy Metals Pollution Bonoua Ivory Coast

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Study of the Evolution of Properties of Concrete Containing Used Tire Aggregates

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Geomaterials 2024年第4期14卷 49-58页

作者： Mamery Adama Serifou Ouaga Jean Bruce Nataniel Gboga Bleh Raoul Ulrich Kouassi Edjikémé Emeruwa laboratoire des Sciences du sol de lEau et de Gomatriaux UFR des Sciences de la Terre et des Ressources Minires Universit Flix Houphout Boigny Abidjan Cte dIvoire Institut National Polytechnique Flix Houphout-Boigny Yamoussoukro Cte dIvoire laboratoire de Gomatriaux et de Gotechnique Dpartement des Sciences de la Terre UFR Environnement Universit Jean Lorougnon Gud Daloa Cte dIvoire

Concrete is generally composed of cement, water, gravel, and sand. However, some research focuses on substituting aggregates with waste materials. In this study, used tires are used as a substitute for gravel. Characteristics such as tensile strength, compressive strength, and porosity were monitored at 7, 14, and 28 days of maturation. The results show that aggregates made from used tires are suitable for concrete production and can replace natural gravel. Regarding the formed concrete, low substitution rates lead to improved concrete properties, but only at an early age. A reaction between the cement and rubber could be the underlying cause. Additionally, the products of this reaction may mitigate the evolution of the compressive strength of the concrete over time.

关键词： Concrete Used Tire Porosity Mechanical Strength

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