The aim of this study is to investigate the effectiveness of annotations in nlultimedia on-screen texts using two presentational modes in enhancing learners comprehension level as well as vocabulary level. The subjects involved are 44 first year Biotechnology students of USIM. The methodology employed is experimental comparison of the performance of two groups of subjects under two different conditions: one using multimedia on-screen text with the annotations of 'text+animation' and the other using multimedia onscreen text with the annotations of 'voice+animation'. The instruments used in this study are the multimedia texts on "transgenesis method' which focuses on the processes involved in the "Protoplast Fusion' as well as the "Agro bacterium mediated transfusion' and a Comprehension Test that assessed the subjects understanding of the reading texts assigned. The neth hod of data analysis used is of descriptive statistics which uses the frequency count of the average (mean) value scores as well as the highest (max) and lowest score (min) in identifying the effectiveness of the multimedia annotations in facilitating the students comprehension level using the two presentational modes. Generally, the overall scores indicate that there is no significance difference in the use of annotations via the two presentational mode - 'text+animation7 and 'voice+animation' as the difference that exist in the scores are small. However, the findings do indicate that the subjects are found to emphasise on the use of their visual sense of modality in facilitating their reading tasks. Subsequently, this has resulted the students that are exposed to the presentational mode of 'text+animation' to do fairly better than the latter group 'voice+animation'. Finally, it is important to highlight here that the annotations (animations) found in the multimedia on-screen text, do to a certain extent, facilitate the students in understanding a science based text due to its ability to build referential connections between the two mental representations in short term memory hence, resulting in better performance in the tasks assigned

The effects of important reaction parameters for enhancing flavour esters formation through lipase-catalyzed reaction were investigated in this study. Various commercial immobilized lipases were used to catalyze the esterification reaction between short-chain fatty acids and alcohols to produce flavour esters which are nonyl caprylate and ethyl valerate which differ in chain length of esters. These synthetic flavour esters with fruity notes are widely used in food, cosmetic and pharmaceutical industries. The effect of various reaction parameters was optimized to obtain a high yield of flavour esters. A maximum percentage for nonyl caprylate with conversion of flavour esters more than 90 % in a solvent-free system was successfully obtained under the following conditions: reaction time (RT), 5 hours; reaction temperature, 40 °C; amount of immobilized lipase, 25 % w/w of total substrate and shaking speed 200 rpm. Compared to ethyl valerate, a maximum percentage conversion of flavour ester more than 80 % in solvent free system was successfully obtained under following conditions: reaction time (RT), 45 minutes; reaction temperature, 40 °C; amount of immobilized lipase, 15 % w/w of total substrate and shaking speed 200 rpm. Comparison between these two ester showed that the chain length give an effect to optimize the reaction condition in esterification reaction.

Series of heterogeneous catalyst were synthesized by the direct immobilization of various concentrations of MoO2(acac)2 and VO(acac)2 on montmorillonite (MMT) K10 clay. The immobilized catalysts were characterized by x-ray powder diffraction (XRD), atomic absorption spectroscopy (AAS), thermal gravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR) with KBr pellet method. The basal spacing for Mo-MMT K10 and V-MMT K10 obtained from XRD analysis suggests that the clay structure were retained. AAS analysis revealed that as the concentration of the metal increased, the elemental compositions of Mo and V complexes on MMT-K10 samples were also increased. The bands that appear in the region of 1300-400 cm-1 from FTIR are attributed to the stretching vibration from SiO2 tetrahedra, indicating the structure of the clay. Besides from the thermal analysis, the higher concentration of metal complexes (Mo and V) immobilized on MMT-K10 structure make them being better hydrophobic nature thus lower the loss of physisorbed water molecules weakly bound to the material.