7 research outputs found

    Investigation of flexural properties of epoxy composite by utilizing graphene nanofillers and natural hemp fibre reinforcement

    Full text link
    This study aims to determine the optimum reinforcement required to attain the best combination of flexural strength of modified green composites (graphene oxide + hemp fibre reinforced epoxy composites) for potential use in structural applications. An attempt was also made for the combination of graphene and hemp fibres to enhance load-bearing ability. The infusion of hemp and graphene was made by the weight of the base matrix (epoxy composite). Results showed that graphene reinforcement at 0.4 wt.% of matrix showed load-sustaining capacity of 0.76 kN or 760 MPa. In the case of hemp fibre reinforcement at 0.2 wt.% of the matrix, infusion showed enhanced load-bearing ability (0.79 kN or 790 MPa). However, the combination of graphene (0.1 wt.% graphene nanofillers) and hemp (5 wt.% hemp fibre) indicated a load-sustaining ability of 0.425 kN or 425 MPa, whereas maximum deflection was observed for specimen with hemp 7.5 % + graphene 0.2 % with 1.9 mm. Graphene addition to the modified composites in combination with natural fibres showed promising results in enhancing the mechanical properties under study. Moreover, graphene-modified composites exhibited higher thermal resistance compared to natural fibre reinforced composites. However, when nanofiller reinforcement exceeded a threshold value, the composites exhibited reduced flexural strength as a result of nanofiller agglomeration

    ijopp Apr-Jun 2009.pdf

    No full text
    Abstract Continuing pharmacy education (CPE) i

    Membrane stabilization as a mechanism of the anti-inflammatory activity of methanol extract of garden egg (<it>Solanum aethiopicum)</it>

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Some observations and reports show that people with high consumption of <it>Solanum aethiopicum</it> (African garden egg) have relief in arthritic pains and swelling. We aimed at assessing the effect of methanol extract of <it>Solanum aethiopicum</it> in experimentally induced inflammation using leukocyte mobilization and vascular permeability tests in rats and human red blood cell (HRBC) membrane stabilization as studies.</p> <p>Methods</p> <p>Twenty five (25) adult Wistar rats of either sex (120 g – 200 g) divided into five groups of five rats each were used for each of the animal models. Groups 2, 3 and 4 were administered varied doses of the extract (100, 200 and 400 mg/kg), while groups 1 (vehicle control) and 5 (treatment control) received normal saline and indomethacin (50 mg/kg) respectively. Vascular permeability was induced by the intra-peritoneal injection of 1 ml of acetic acid and monitored using 0.5 ml intravenous injection of 1% Evans blue solution. Leukocyte mobilization was induced by the intra-peritoneal injection of 0.5 ml of 3% agar suspension in normal saline. Heat and hypotonicity induced heamolysis of HRBC membrane was used to assess membrane stabilization.</p> <p>Results</p> <p>The methanol extracts of garden egg significantly and dose dependently reduced (p≤0.05) the acetic acid induced vascular permeability and agar induced leukocyte mobilization in rats. The percentage inhibitions of induced vascular permeability were 21 ± 3.39, 25 ±1.92 and 60 ± 3.81 for the 100, 200 and 400 mg/kg of the extract while the inhibitions of the agar induced leucocyte migration were 23 ± 2.17, 26 ± 1.58 and 32 ± 1.58 for the 100, 200 and 400 mg/kg of the extract respectively. The extract also, at doses of 100, 200, 400, 600 and 800 μg/ml significantly inhibited heat induced lysis of the human red cell membrane with values of 66.46 ± 2.89, 65.14 ± 4.58, 46.53 ± 2.52, 61.88 ± 4.51and 86.67 ± 3.06 respectively.</p> <p>Conclusions</p> <p>These results show that methanol extract of <it>Solanum aethiopicum</it> has anti-inflammatory properties and can reduce inflammatory injury and tissue damage.</p
    corecore