Extraction of cellulose from oil palm empty fruit bunch using eco-friendly solvents for preparation of transparent cellulose thin film

The purpose of this research is to extract the cellulose using eco-friendly reagents of hydrogen peroxide and formic acid and determine the optimum reaction time for delignification process. The extracted cellulose and characterised using FTIR, TGA and PSA. The percentage yield of extracted cellulose were calculated. The highest yield was found to be 65.78 % at reaction time 120 min. The FTIR spectral studies confirm the removal of lignin from the delignified cellulose at peak 1613 cm−1 and the TGA result shows the thermal degradation of extracted cellulose at 329.04, 329.92 and 330.99 °C at reaction time 60, 90 and 120 min. The PSA studies provided the evidence of extracted particle size of the cellulose become finer as the reaction time increase. The particle size observed for delignified cellulose at 60, 90 and 120 min are 68.4, 64.6 and 57.3 μm. The extraction of cellulose and characterization to determine the optimum reaction time was able to obtain. From the result obtained, it can be concluded that the longer the reaction time, the higher the percentage yield of cellulose extracted. Film formation was later carried out using the extracted cellulose from different reaction time.

Fatigue in Shift Work on Stamping Division Workers of PT. Toyota Motor Manufacturing Indonesia

Various health problems are known from shift works. PT. Toyota Motor Manufacturing Indonesia (TMMIN) as a car manufacturing in Indonesia is a large industry that applies a shift work system for the workers. This study aims to see the relationship between shift work system in the Stamping Division of PT. TMMIN. The measurement works by using the reaction time method on the worker the shift (shift I/morning and shift II/night) and non-shift during the workday flash. Based on the average measurement of reaction time for the shift workers I was 284.79 milliseconds and shift worker II was 307.76 milliseconds. The risk of reaction time increase was 3.222 times due to shift works compared to non-shift workers. Based on the value of reaction time, shift workers in PT. TMMIN recommends a repair per shift after work on the eighth day for shift I and twelfth day for shift II.

The Effects of Object Independent Vibration on Visual Identification Efficiency

Choosing reaction time as dependent variable, the paper discussed the effects of object independent vibration on visual identification efficiency, which was under different vibration frequency, amplitude, direction and the position of target gap. The major experiment results indicated that the reaction time increase exponentially with the increasing of vibration frequency and amplitude within a certain range. This will provide a scientific basis for design optimization and vibration control of human-machine system.