No abstract

No abstract

The objective of this study was to determine the effect of chemical treatment on the coconut fiber surface morphology. This study is divided into three stages, preparation of materials, treatment and testing of coconut fiber. The first treatment is coconut fiber soaked in a solution of NaOH for 3 hours with concentration, respectively 5%, 10%, 15%, and 20%. The second treatment is coconut fiber soaked in KMnO 4 solution with a concentration of 0.25%, 0.5%, 0.75%, and 1% for 3 hours. The third treatment is coconut fiber is soaked in H 2 O 2 solution with a concentration of 5%, 10%, 15%, and 20% for 3 hours. At each treatment the fiber is dried in an oven at a temperature of 90 o C for 5 hours. Coconut fibers that had been the first, second, and third treated, sorted out for chemical composition, single fiber tensile and SEM testing. Tensile strength of single coconut fiber was tested following ASTM 3379-02 by using a tensile testing LR10K Plus 10 kN Universal Materials Testing Machine. The fiber surface morphology was examined using electron microscopy Vega3 Tescan Scanning Electron Microscope (SEM) at 5kV voltage, and X-ray diffraction, 30 kV, 15 mA, at scan speed 2.000 deg./min . The result shows that the highest tensile strength of the fiber obtained in the first treatment namely N4. In general the mechanical strength of the fiber decrease slightly however, the fiber surface morphology becomes rough. NaOH treatments cause crystallization on the surface of the fiber. Crystallinity index was decreased with increasing concentration of NaOH. The second treatment caused the trench grooves on the surface of the fiber that can improve bonding between fiber and matrix.

Microalgal biomass is the most promising and attractive alternative to replace the terrestrial crop utilization for renewable biomass fuel feedstock. The potential for biomass fuel is due to its fast growth rate and high ability for CO 2 fixation as compared to terrestrial vegetation. There are many species in the globe, growing both in marine and freshwater. In this work, the marine microalgae Nannochloropsis oculata (N. oculata) had been investigated in terms of potential abundance and physicochemical properties, which determine its feasibility as biomass fuel feedstock. The chemical composition was evaluated by energy-dispersive X-ray spectrometry, and the proximate analysis was done by performing experiments in the thermal gravimetric analyzer. During 7 days of cultivation, the average rate of increase in algal biomass was about 1.5 9 10 6 cells/ml/day. The proximate analysis of N. oculata indicated that it had compositions of low moisture content and fixed carbon, whereas high volatile matter and ash content, i.e., 3.99, 8.08, 67.45, and 24.47 %, respectively. The energy content, which was calculated through the proximate analysis results, was 16.80 MJ/kg. The algal biomass and its residue after 1,200°C were characterized by Fourier transform infrared spectroscopy to investigate their chemical macromolecular compounds. This present study concludes that N. oculata is feasible as biomass fuel feedstock, either to direct or co-combustion mode by giving special attention to high ash content.

No abstract

No abstract

No abstract

The Chinese philosophy of Confucianism said “What I heard I forgot, what I see, I remember, what I do, I understand.” During this time, most of the teaching and learning process relies on viewing and listening modalities only. As a result, much information does not last long in memory as well as the material understanding achieves became less deep. In studying anatomy science, drawing is one of effective important methods because it is an integration of ideas and knowledge of vision thereby increasing comprehension and learning motivation of college students. The purpose of this research is to know the musculoskeletal anatomy comprehension by drawing learning method in Medical Faculty student. This research uses observational analytic design with the cross-sectional design. Total sampling was done to the entire student of Physiotherapy Study Program in 2012, 2013, and 2014, Medical Faculty of Udayana University. The average value of musculoskeletal anatomy of the student in 2012, 2013, and 2014 sequentially are 31.67, 33.57, and 45.00, respectively. Normality test with Shapiro-Wilk and homogeneity with Levene's test showed normal results and homogeneous. One-way ANOVA test between groups showed a significant result that is 11.00 (P<0.05). It is concluded that the drawing method can improve the musculoskeletal anatomy comprehension in Medical Faculty student.