Solar thermal system or solar water heater system is one of the applications used to produce hot water in the residential sector. This paper describes HAZOP analysis and reliability assessment to evaluates the potential hazard and system probability for the closed loop solar thermal system applied for the residential area. Hazard identification for the main system components is analyzed while Fault Tree Analysis (FTA), Reliability Block Diagram (RBD) and Weibull distributions performed to determine the reliability for the overall system. The result shows that there are 49 potential hazards for the system with failure probability at 0.23822 and the reliability is 0.9693. Subsequently, this study determined the potential hazards for the system which can be anticipated by the residential consumer for the safety aspect. Furthermore, the evaluated reliability result shows that the application of closed loop type solar water heater system at residential premises is highly recommended due to its long lasting operational condition.
The present work investigated the antioxidant properties and antihypertensive activity of
magnesium orotate (MgOr) using various established in vitro assays, such as β-carotene
bleaching activity, 1,1-diphenyl-2-picrylhydrazyl (DPPH), and nitric oxide scavenging activity as well as angiotensin converting enzyme (ACE) inhibitory activity. Magnesium orotate
nanoparticles (MgOrGANPs) were prepared using the gum arabic (GA) as stabiliser coatings
for nanoparticles through freeze-drying method. The in vitro cytoxicity of MgOrGANPs
against human breast cancer MCF7, liver cancer HepG2, and colon cancer HT29 was investigated. The nitric oxide (NO) and DPPH scavenging assays of MgOrGANPs showed a
dose-dependent trend, while 500 and 200 µL/mL were significantly more effective than the
other concentrations with an IC50 of 89.56 µg/mL and 63.22% DPPH scavenging capacity
respectively. The exposure of human cancer cells to MgOrGANPs at 1.56 – 1,000 µg/mL
using 3-)4,5-dimethylthiazol-2-yl(2,5-diphenyl tetrazolium bromide (MTT) inhibited the
growth of cell lines examined in a dose-dependent manner. Hence, MgOrGANPs may have
great potential to be applied for cancer treatments.
Biocellulose (BC), produced by Acetobacter xylinum (0416), was carried out using three types of medium
composition under static surface culture. The media used in this experiment included CWHSM (Coconut
water in Hestrin-Schramm medium), CM (Complex medium) and HSM (Hestrin-Schramm medium).
CWHSM and CM used coconut water from agro-waste as the main source of sugar. The fermentation
was conducted for 12 days and the results of BC dry weight, cell entrapped, pH medium and productivity
were evaluated and compared. The results show that CWHSM is the most suitable medium for BC
production with a productivity of up to 0.044 g l
-1
day
-1
.