Summary
This work was conducted to study the influence of particle size and shape on the flow behaviour of semi‐ripe plantain powders. An improved plantain variety (Big Ebanga), two hybrids (FHIA 21 ...and PITA 3), and a local variety (Corne 1, as reference material) were powdered by successive drying, milling, and sieving into three granulometric classes: unsieved (<500 µm), fine fraction (<180 µm; class 1), and coarse fraction (between 180 and 500 µm; class 2), thus differing in particle size distribution. Physical properties (water activity, particle size distribution, shape factors) were characterised and flow properties (basic flowability energy, compressibility, fluidisability, cohesion, etc.) were investigated using the FT4 powder rheometer. Convexity of unsieved and fine powders was slightly higher than for coarse powders. Fine powders of all plantain varieties were found to have the lowest water activity and the lowest flowability in unconfined conditions. Unsieved and fine powders presented a fluidised state at the end of the FT4 standard aeration test and their minimum fluidisation velocity was low, confirming the good fluidisability of these powders.
Influence of particle size on the physical parameters and flow properties of semi‐ripe plantain hybrid powders.
Impact of Local Clay Mineral on the Toxic Waste Kouadio, Olivier; Kouadio, Konan-Kan Hippolyte; Ouffoue, Koffi Sébastien
Water, air, and soil pollution,
02/2020, Letnik:
231, Številka:
2
Journal Article
Recenzirano
This work investigated the impact of a clay mineral on toxic waste. The Ivorian Anti-pollution Center discovered the toxic waste from Probo Koala boat on 21 August 2006. This boat had been used to ...refine oil named naphtha of cokéfaction by Trafigura firm in the sea. The process of refining consists of caustic sodium carbonate washing and produced toxic waste. These toxic wastes have been unloading in 13 zones of the Abidjan district: Akouédo, Abobo, Abobo Alépé road (Djibi village), civile prison road (MACA), industrial zone of Koumassi, Port-Bouët - Vridi CAP Logistic (Rue Saint-Sylvestre)… This situation caused a socio-political crisis and generated the death of many people. To solve this problem, one first part has been excavated and sent to France to be incinerated. A second part is used to be a biopile for bioremediation. After these two processes, the rest of toxic waste remained in the place where they have been unloaded. The analyses of these toxic wastes show that polycyclic aromatic hydrocarbons (PAHs), oxygenated polycyclic aromatic compounds (O-PACs), volatile aromatic compound (VAC), mercaptan and sulfur molecules, and also heavy metal and organometallic are the principal polluters of these contaminated soils. From a mineralogical viewpoint, the tropical climate soils of Ivory Coast in general and district of Abidjan in particular constituted of about 50% of kaolinite, 30 to 40% of smectite, and 10 to 20% of illite (OSTROM
1993
). In this study, we want to show the impact of this local clay on toxic waste.
Human activities and climate change are currently dominant processes that affect hydrological processes, resulting in alterations in water and sediment flows. Evaluation of the settling velocity of ...suspended solids is a critical parameter in modelling sediment transport. In this study, we investigated seasonal changes in suspended solids’ settling velocity and trapping capacity in the presence and absence of water turbulence on a dam reservoir. Using key parameters such as flow rate, mean settling velocity (V¯), critical velocity (vc), suspended solids concentration, ratio V¯/vc, and shape parameter ‘r’, the trapping capacity on the dam reservoir on the Lobo River in a tropical region was estimated. The results show that, considering the settling velocity of suspended solids, following the Gamma distribution law remains an innovative solution proposed to evaluate the trapping capacity in water reservoirs. The results show that the mean suspended solids settling velocity V¯ is well above the median rate V50%. For a parameter V¯/vc ≥ 4, there is an increase in the trapping capacity of the water retention. As established, a large proportion of the sediment is trapped. Furthermore, for a parameter V¯/vc ≤ 4, a decrease in the trapping capacity of the Lobo River water reservoir is observed.
Lymphatic filariasis (LF) is a neglected tropical disease that can cause hydrocele and its associated stigma, loss of economic productivity, and depression. Hydrocele surgery is an essential part of ...LF morbidity management but can be difficult for national programs to implement. To improve access to hydrocele surgeries in Côte d'Ivoire, we provided a WHO-certified surgical training for six surgical teams from five health districts in Côte d'Ivoire. We then evaluated the surgical outcomes and assessed the impact of hydrocele surgery on quality of life of hydrocelectomy patients. Preoperative and operative records were reviewed to describe baseline hydrocele characteristics and operative details. Postoperative interviews were conducted 4 to 6 months after surgical correction using a standardized questionnaire. Seventeen men underwent surgery during the training and were available for an interview at the 6-month visit. At the time of 6-month follow-up, 11/17 (64.7%) reported improvement in activities of daily living and reduction in difficulties with work, 8/17 (47.1%) reported an improved economic situation, 15/17 (88.2%) reported improved social interactions, and 15/16 (93.8%) reported improved sex life after surgical correction. Three patients (17.6%) had minor postoperative complications, but none required hospitalization. All 17 patients who were available for an interview were satisfied with their surgery. Surgical hydrocelectomy training in Côte d'Ivoire was well received and provided life-altering health improvements for participating patients across multiple domains of life. Support to scale up surgical capacity for this neglected problem is needed.
This study is aimed at evaluating the physicochemical and sensory characteristics of developed instant foutou flour. Blanched semiripe plantain dried flakes, blanched/unblanched cassava dried flakes, ...and cassava starch were blended in the proportions 70 : 20 : 10 (FTF1), 80 : 30 : 0 (FTF3/FTF2), and 80 : 0 : 20 (FTF4), respectively, and ground. Foutou made from FTF1 and FTF2 were the most similar to traditional foutou (FTTRAD) for texture attributes. These foutou were fairly stick (5.66-5.73), firm (5.66-6.04), easy to mold (6.13-6.20), and pasty (6.00-6.26). FTF1 was appreciated and preferred by consumers because its color is relatively more yellow and its sweetness is relatively higher than those of other reconstituted foutou. All studied foutou flours exhibited low moisture content (6.09%-8.33%) and values of aw<0.6. FTF1 and FTF2 formulations had the highest ash (1.71%-1.73%) and protein (4.08%-4.53%) contents. FTF1 had the highest a∗ value (1.80) and total sugar (TS) content (7.77%).
Drinking water supply in the Lobo catchment is based mainly on surface water. In recent years, the adverse effects of climate change and strong population growth have led to increasing uncertainty ...about the availability of surface water and growing interest in groundwater in this region. Therefore, to ensure sustainable management of this resource, it is necessary to characterise and understand this groundwater system. This characterization requires knowledge of the geometry and structure of this aquifer system, which is a prerequisite for ensuring future water supply from groundwater resources. This aquifer system, which is the subject of this study, has never been the subject of a study aimed at characterising it and getting to know it better.This study aims to improve the knowledge of this aquifer system by elaborating the geometry of this aquifer system through the study of drilling data and electrical resistivity tomography (ERT). The results show that weathering of the granitic rocks in the Lobo catchment leads to the development of composite aquifers at two levels: a shallow saprolite aquifer overlies in places by a thick layer of ferruginous crust, and a deeper and very thick fractured aquifer. This shallow weathering aquifer, fed directly by precipitation, is tapped by conventional large diameter wells that are generally not immune to seasonal fluctuations. For sustainable management of this resource, an assessment of its recharge should be undertaken in addition to this study of the geometry of this aquifer system. The results of this study of the geometry of the Lobo catchment aquifer system improved the understanding of this aquifer system and will assist in groundwater exploration in this area.
Determination of groundwater recharge is a major challenge in areas where rainfall is generally abundant. Variability and uncertainty are inherent in the estimation of recharge, and several methods ...are therefore recommended for its estimation at a regional level. In this study, we evaluated several methods for estimating recharge: the web GIS-based automated hydrological analysis tool (WHAT), water table fluctuation (WTF), hydrograph analyses, a recession curve displacement method, graphical separation, and empirical formulas. The annual recharge estimated by combining direct recharge and base-flow varied from 84 mm in 2019 to 66.4 mm in 2020. The mean direct recharge was about 44 mm in 2018 and 57.3 mm in 2019, representing about 4% and 5% of the respective rainfall. In 2020, this direct recharge was 43 mm, or about 6% of rainfall, around 25% lower than in 2019. Base-flow separation methods and recession curve displacement generally gave low results, whereas modified empirical formulas gave results close to those of the WTF method and were considered more consistent and reasonable. The regression curve displacement method implemented in the United States geologic survey (USGS) RORA program was found to be unsuitable for the study area. However, the other methods presented more reasonable results and could be used to estimate groundwater recharge in the study area.
This study was to determine the hydrogeological and geoelectrical parameters affecting the productivity of water boreholes in the Daloa commune. Using the Schlumberger configuration, we carried out ...15 parallel and perpendicular electrical profiling and 40 Vertical Electrical Soundings (VES). We also performed Electrical Resistivity Tomography (ERT) with a pole-dipole configuration at one site. The data processing allowed the identification of the different layers of the subsurface and their geoelectric properties that influence the productivity of the boreholes in the study area. These geoelectric data have shown that the productivity of the boreholes is more related to the conductive anomalies (W and U) than to the vertical electrical sounding. The processing of the hydrogeological data has shown that borehole productivity in the study area using Self-Organising Map (SOM) is a function of the hydraulic conductivity but also the thickness and density of the fracturing. Sixteen new boreholes on the main campus of Jean Lorougnon Guede University, Daloa, validate these results. The yield of these productive boreholes varies between 7.5 and 22 m3/h, with an average of 15.2 m3/h, four times higher than the values usually obtained in the study area. The success rate of these boreholes is about 70 %. This study has shown how effectively integrating hydrogeological and geoelectrical parameters provides information on the lithology and structural conditions in the subsurface necessary for productive drilling.
Lobo River Catchment (Côte d’Ivoire)
In this study, four regional climate models (RCMs) (RC4; CCLM4–8–17; RACMO22T and REMO) for the 2030 and 2050 periods compared to the reference period ...(1986–2005), combined with a simulation of land use and land cover (LULC) with Land Change Modeler, are used to drive the CEQUEAU model to quantify their impact on inflows to the Lobo River reservoir. 1988–2006 is used as a calibration period, whereas 2007–2015 is used for the validation. Three scenarios were used. First, varying LULC and keeping climate parameters static over the baseline period (scenario 1); in scenario 2, varying RCMs and keeping LULC static over the baseline period and in scenario 3, simultaneous variation of LULC and RCMs.
CEQUEAU showed good performance during calibration and validation: NSE (0.7, 0.75); R² (0.83, 0.65); PBIAS (14.1%, 12%) and RMSE (0.83, 2.15). The results show that a decrease in precipitation by 2030 (−14.6%), by 2050 (−15.2%) under scenario 2 (RCP 4.5 and 8.5) and by − 6.1% under RCP 4. 5 (Scenario 3), we observe an increase in runoff of 10.8–18.87% (Scenario 1), 1.2–4.46% (RCP4.5), 3.35% and 2.7% (RCP8.5) (Scenario 2) and 6.58–11.83 (RCP 4.5), 14.83–17.72% (RCP 8.5) (scenario 3). Changes in LULC were identified as the main causes, rather than climate variability.
Display omitted
•Cordex-derived RCM data are bias-corrected for a regional impact study.•Future land use (2030, 2050) is projected using the Land Change Modeler (LCM).•A hydrological model is calibrated and validated to simulate watershed hydrology.•Isolated and combined effects of climate and LULC changes on water resources are quantified.
Saba senegalensis fruit is traditionally collected and sold on the Ivorian markets, although it is considered as an underutilized species in favour of commercial fruits. The present study aimed at ...providing data on the nutritional value of Saba senegalensis fruit in comparison with widely valued fruits. Saba senegalensis pulp as well as dessert banana, papaya and pineapple pulp were used as study material. After an evaluation of the biochemical parameters, a principal component analysis (PCA) was used to highlight the nutritional potential of the different fruits. The results showed that the physicochemical parameters varied from one fruit to another. The Saba senegalensis fruit stood out from the other three fruits by its high antioxidant activity (IC50 = 39.80 ± 0.45 mg/ml), its high concentration of polyphenols (600.94 ± 5.27 mg EqA. G / 100 g), flavonoids (245.09 ± 19.10 mg EqA.G / 100 g), vitamin A (1.96 ± 0.03 mg/100 g), Ca (29.19 ± 0.17) and Fe (2.51 ± 0.06 mg/100 g). These nutritional constituents are far superior in Saba senegalensis pulp to those of banana, papaya and pineapple. Thus, its nutritional potential could be a major asset for its consumption and valorisation
PDF
