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Ion–exchange properties of the fabricated activated carbon black nanoparticles of ACBNPs20_17 code have been properly studied using several various concentrations of 0.001, 0.003, 0.005, 0.007 and 0.009 M sodium hydroxide (NaOH) solutions. The study was performed by mean of measuring both hydroxyl anions (OH–) quantity and electrical conductivity of the NaOH solution before and after it flowed down through the ACBNPs20_17 material at 1 drop per second flow rate due to gravitation force for four cycle’s time. The study was aiming to correlate between the properties of anion-exchange and capability of adsorption of the ACBNPs20_17 material compared to that of the pristine carbon black (CB) powder. This research recorded that there was a competition between hydroxyl anion-exchange and hydroxyl anion adsorption. It was clearly known just the concentration of 9 mM NaOH provided hydroxyl anion-exchange on both ACBNPs20_17 material and CB, whereas the lesser concentrations of 1, 3, 5 and 7 mM NaOH provided hydroxyl anion adsorption rather than anion-exchange. In this case, anion-exchange capacity of the ACBNPs20_17 material was higher than that of the pristine CB materials. Ultimately, it can be concluded that adsorption process happened first before anionexchange process, and the later would precede when the concentration of NaOH solution feed higher enough, i.e. about equal or more than 0.009 M. [ABSTRACT FROM AUTHOR]

Ergonomics has gained attention and take into consideration by the workers in the different fields of works recently. It has given a huge impact on the workers comfort which directly affects the work efficiency and productivity. The workers have claimed to suffer from the painful postures and injuries in their workplace. Musculoskeletal disorders (MSDs) is the most common problem frequently reported by the workers. This problem occurs due to the lack of knowledge and alertness from the workers to the ergonomic in their surroundings. This paper intends to review the approaches and instruments used by the previous works of the researchers in the evaluation of the ergonomics. The two main assessment methods often used for ergonomic evaluation are Rapid Upper Limb Assessment (RULA) and Rapid Entire Body Assessment (REBA). Popular devices are Inertial Measurement Units (IMU) and Microsoft Kinect. [ABSTRACT FROM AUTHOR]

This paper proposes on the design of a walker for the prevention of falling among elderlies or patients during rehabilitation whenever they use a walker to assist them. Fall happens due to impaired balance or gait problem. The assistive device is designed by applying stability concept and an accelerometric fall detection system is included. The accelerometric fall detection system acts as an alerting device that acquires body accelerometric data and detect fall. Recorded accelerometric data could be useful for further assessment. Structural strength of the walker was verified via iterations of simulation using finite element analysis, before being fabricated. Experiments were conducted to identify the fall patterns using accelerometric data. The design process and detection of fall pattern demonstrates the design of a walker that could support the user without fail and alerts the helper, thus salvaging the users from injuries due to fall and unattended situation. [ABSTRACT FROM AUTHOR]

The effects of solar radiations on physical properties and molecular structures of 200 nm polystyrene nanospheres (PSN) coated on silicon wafer were explored by field emission scanning electron microscope (FESEM) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectrometer. It is revealed the particles shape of PSN changed from spherical to dumbbell-like shape after solar irradiation. Reduction of the PSN size as much as 23.79% after 5 minutes exposure was also observed in PSN particles. We believed that some of the phenyl moieties of polystyrene broke down to facilitate carbon-carbon cross linkage bonds intra- as well as inter-PSN particles and were shown by ATR-FTIR spectrums. These results proven the shrinkage of PSN particles were caused by the change of the molecular structure of the irradiated PSN to be much more dense material. [ABSTRACT FROM AUTHOR]

We study the growth of TiO2 thin film using simple spin coating technique. In this paper, the effect of heat treatment to the TiO2 thin film was investigated within heat treatment in open and closed environment. In open environment, the heat treatment was carried using hot plate and in closed environment the heat treatment was carried in an oven. TiO2 solution was prepared with titanium butoxide as precursor, glacial acetic acid as a chelating agent, ethanol as solvent and deionised water. Triton X-100 acts as a stabilizer to avoid precipitation in solution and to increase the conductivity of films. To our knowledge there are no research comparing the influence of open and closed environment during heat treatment. Smaller grain size was found in nanostuctured TiO2 thin film with closed environment. At low magnification of FESEM image, it was shown that the crack-free was occur when nanostuctured TiO2 thin film is in closed environment compared to open environment. At high magnification there no significant on the structure was observed. In addition, no change in their crystallinity was found. The resistivity (current versus voltage) have smaller different due to the different structure on nanostructured TiO2 thin film. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) thin films, micro- and nanostructures are promising candidates for applications in optoelectronic devices. In this work, low cost sol-gel spin coating and hydrothermal techniques were used to fabricate the ZnO films on glass substrates and ZnO microstructures on oxidized silicon substrates, respectively. The structural properties of the ZnO samples were examined using scanning electron microscope (SEM) and atomic force microscope (AFM). The influence of precursor concentration in the sol-gel processes on the properties of the ZnO films and microstructures was investigated and will be discussed in this paper. [ABSTRACT FROM AUTHOR]