Synthesis of bioactive glass using cellulose nano fibre template.

This study introduces a templating approach using a cellulosic suspension to create a porous SiO2-CaO-P2O5-Na2O bioactive glass material. Sol-gel approach was used as the synthesis method. Carbon nanofibers in suspension form was used as the templating material. The amount of CNF used in the experiment ranged from 5% to 25% by volume. The morphology, porosity, crystallinity of the combeite phase, mechanical and chemical properties of the BG samples were examined. The findings show that the templating method had no effect on the formation of the required functional elements, such as Si, Ca, Na and P. The porosity of the BG materials improves by 15% after templating compared to the neat sample. The formed pores were assumed to be homogenous based on the uniform adsorption and desorption BET profiles. The crystallization mechanisms during the sintering process were affected by the templating approach, indicating the need for a specific amount of template to be used in the preparation step. Both the sintering temperatures and the CNF content affected the formation of the combeite phase. The BG samples had excellent mechanical properties and are suitable for use in cancellous bone applications. As a result, this study shows a novel method for synthesizing porous bioactive glass materials via the sol-gel method and a CNF suspension as a template.

Effect of physical pretreatment on dilute acid hydrolysis of water hyacinth (Eichhornia crassipes).

Effects of different physical pretreatments on water hyacinth for dilute acid hydrolysis process (121 ± 3 °C, 5% H(2)SO(4), 60 min) were comparatively investigated. Untreated sample had produced 24.69 mg sugar/g dry matter. Steaming (121 ± 3 °C) and boiling (100 ± 3 °C) for 30 min had provided 35.9% and 52.4% higher sugar yield than untreated sample, respectively. The highest sugar yield (132.96 mg sugar/g dry matter) in ultrasonication was obtained at 20 min irradiation using 100% power. The highest sugar production (155.13 mg sugar/g dry matter) was obtained from pulverized samples. Hydrolysis time was reduced when using samples pretreated by drying, mechanical comminution and ultrasonication. In most methods, prolonging the pretreatment period was ineffective and led to sugar degradations. Morphology inspection and thermal analysis had provided evidences of structure disruption that led to higher sugar recovery in hydrolysis process.