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Research Article
Influence of the Addition of Palm (Borassus Aethiopum Mart.) Fibers on the Durability of Compressed Earth Blocks
Stephane Koffi
,
Athanas Konin*
Issue:
Volume 13, Issue 3, September 2024
Pages:
37-45
Received:
11 July 2024
Accepted:
7 August 2024
Published:
20 August 2024
Abstract: This study aims to determine the influence of the content and length of the palm (borassus aethiopum mart.) fibers on the physical, mechanical and thermal properties of Compressed Earth Blocks (CEB). Three fiber contents (0.2%, 0.4% and 0.8%) of different lengths (10 mm, 20 mm, or 40 mm) were used to make CEB. CEB with 0% fiber content were manufactured to serve as control samples. CEB specimens stabilized with palm fibers or not were subjected to various tests according to standard XP P 13-901 for the determination of the following properties: dry density, water absorption, dry compressive strength, abrasion resistance and thermal conductivity. The results show that the dry density of CEB decreases from 4% to 7% when the content and length of the fibers increase respectively from 0.2% and 10 mm in length to 0.8% and 40 mm in length. The water absorption of fiber-containing CEBs ranges from 14% to 22% with increasing fiber content and length. The results also indicate that the mechanical and thermal properties are improved for well-chosen fiber contents. Thus, the dry compressive strength of the fibers increases by more than 13% for a fiber content of 0.2% and a length of 10 mm compared to CEB with 0% fibers. On the other hand, the optimal abrasion resistance values are obtained for a fiber content of 0.4% and a length of 40 mm. For all CEBs, the thermal conductivity values vary from 0.51 W/mK to 0.38 W/mK when the fiber content varies from 0.2% to 0.8%. Overall, palm fiber content has a greater influence on the measured physical, mechanical and thermal characteristics than fiber length.
Abstract: This study aims to determine the influence of the content and length of the palm (borassus aethiopum mart.) fibers on the physical, mechanical and thermal properties of Compressed Earth Blocks (CEB). Three fiber contents (0.2%, 0.4% and 0.8%) of different lengths (10 mm, 20 mm, or 40 mm) were used to make CEB. CEB with 0% fiber content were manufac...
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Research Article
A Comparative Study of Fluoride Removal Using Bovine and Goat Bone Chars
Issue:
Volume 13, Issue 3, September 2024
Pages:
46-54
Received:
3 September 2024
Accepted:
20 September 2024
Published:
29 September 2024
Abstract: Overexposure to fluorides causes dental, skeletal, and crippling fluorosis. Population growth and droughts in Kenya recently necessitated the sinking of boreholes to supply drinking water. The water fetched from the boreholes contains a high concentration of fluorides, consequently increasing the prevalence of dental fluorosis. Bone char remains a sustainable adsorbent to remove fluorides from drinking water as it is environmentally friendly, has high efficiency, is easy to use, and is low cost compared to other adsorbents or fluoride removal methods that may be technically non-feasible in rural communities. This study compared the fluoride removal using bovine and goat bone chars. Bovine and goat bone chars were prepared by calcining in a muffle furnace at 400°C and 600°C. Bone chars made at 400°C appeared gray while those made at 600°C appeared darker. Bone char was activated using 1 M H2SO4 at a ratio of 40 ml per 2 g of bone char and a contact time of 24 hours. The activated bone chars also appeared grey. The surface functional groups were examined by infrared spectroscopy (FT-IR), which revealed similar functional groups in both bovine and goat bone char and their activated parts, with notable differences in peak depths. The amount of inorganic materials was determined by portable X-ray fluorescence (XRF) which showed high concentrations of Ca, P, Mg, Si, Al, Fe, S, K, Mn and Ti in decreasing concentrations before and after using H2SO4. The prepared bone chars adsorbed fluorides from a concentration of 2 ppm to below WHO-recommended fluoride limits in 30 minutes, with bovine bone chars removing 66.8% and goat bone chars 61.8% of the initial fluoride concentrations.
Abstract: Overexposure to fluorides causes dental, skeletal, and crippling fluorosis. Population growth and droughts in Kenya recently necessitated the sinking of boreholes to supply drinking water. The water fetched from the boreholes contains a high concentration of fluorides, consequently increasing the prevalence of dental fluorosis. Bone char remains a ...
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Research Article
Fabrication and Characterization of Alkyl-Functionalized CNFs/Cellulose Acetate Polymer Nanocomposites
Issue:
Volume 13, Issue 3, September 2024
Pages:
55-63
Received:
31 August 2024
Accepted:
19 September 2024
Published:
29 September 2024
Abstract: Carbon nanofibers (CNFs) are widely used to fabricate nanocomposites with enhanced properties. The emergent properties of the nanocomposites depend on the initial properties of the CNFs and how the fibers have been dispersed within the polymer matrix. This study looks at the fabrication of nanocomposites using dodecyl, butyl, and acetyl functionalized CNFs with cellulose acetate as the polymer matrix. The CNFs were prepared by electro-spinning, and functionalization was achieved using alkyl halides in the presence of lithium. Scanning Electron Microscopy (SEM) showed that the fibers were well embedded in the polymer Matrix, Thermal Gravimetric Analysis (TGA) of the nanocomposite revealed a slight increase in the degradation temperatures of the nanocomposites as compared to the blank sample, the aggregate loss of weight of the samples was about 80%. Dynamic Mechanical Analysis (DMA) of the nanocomposites showed increased stiffness and modulus storage by an average of 450MPa for butyl and dodecyl-functionalized CNFs, however, the storage modulus values of the nanocomposites generally decreased with an increase in temperature. The glass transition temperature of the nanocomposites was higher than that of the reference sample by an average of +36°C. Conductivity measurements of the nanocomposites showed no changes at lower frequencies of 1x102 - 4x104Hz. However, the values started increasing at peaked at 5x107Hz. The conductivity measurements revealed that the nanocomposites exhibited higher conductivity peaks at specific frequencies compared to the reference sample, indicating an enhanced electrical property of the nanocomposite. The study successfully fabricated nanocomposites with enhanced mechanical, thermal, and dielectric properties using functionalized CNFs.
Abstract: Carbon nanofibers (CNFs) are widely used to fabricate nanocomposites with enhanced properties. The emergent properties of the nanocomposites depend on the initial properties of the CNFs and how the fibers have been dispersed within the polymer matrix. This study looks at the fabrication of nanocomposites using dodecyl, butyl, and acetyl functionali...
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