Design and analysis of water quality monitoring and filtration system for different types of water in Malaysia

Water pollution always occurs in Malaysia due to industrial, construction, agriculture, and household activities. River pollution can disturb water supply that eventually affects business and household activities. Thus, water quality monitoring system is needed to detect contaminated water. We developed a water quality monitoring and filtration system controlled by Arduino. The proposed system was designed in Proteus software and ThingSpeak platform was used for real-time monitoring. The main objective of the study was to compare water quality of river, lake and tap water in terms of pH, temperature, turbidity, electrical conductivity and oxidation-reduction potential. If the water quality was not satisfied, the water sample would be filtered through filtration system. Water turbidity level, pH, temperature, electrical conductivity, and oxidation-reduction potential for filtered and nonfiltered water were compared and analyzed according to international and national water quality standard. Besides that, statistical analysis such as box plot and one-way analysis of variance test was applied to validate data from the system. The real-time water quality monitoring system was implemented through data storage, data transfer, and data processing. The system was connected to wireless fidelity whereas the output data was sent to the user and monitored by ThingSpeak. The system can be further upgraded and scaled up to be applied in the main tank at our home or factory. The outcome of this research can be used as a reference for further study on lake and river pollution monitoring system.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13762-022-04192-x.

Thermal studies on Arabic gum - carrageenan polysaccharides film

<p>The main objective of this work is to develop film and study the thermal characteristics of polysaccharides films at various concentration of carrageenan in the mixture by calculating activation energy of polysaccharides films. There were four (4) film samples of two polysaccharides combination; arabic gum (AG) and carrageenan (C) with different formulations; sample A, sample B, sample C and sample D prepared. Sample A film is the control sample that contained only arabic gum and distilled water (DI) with 40% weight arabic gum per volume DI water (w/v%). Meanwhile for sample B and C were prepared with concentration 40 w/v% of Arabic gum and two differents of carrageenan concentrations; 1 w/v% and 10 w/v% respectively. Polyethylene glycol 400 (PEG 400) as a plasticiser was added into sample D film. The sample films were thermally characterized using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) under nitrogen atmosphere. The major thermal transitions as well as, activation energies of the major decomposition stages were determined. Sample A and B films exhibited the highest (112.43 kJ/mol) and the lowest (102.89 kJ/mol) activation energy of thermal decomposition, respectively. The activation energies were lower at larger amounts of sulfate groups from carrageenan on the degradation reactions. The DSC trend for all samples shows two (2) major intense peaks recorded in the DSC thermograms; an endothermic transition at temperature around 100^°C and followed by an exothermic transition at temperature around 300^°C. The endothermic transition is due to the heat absorption for dehydration of water, H2O and the decomposition of samples process. Meanwhile, the exothermic transition is caused by the formation of H₂O, CO and CH₄ in polysaccharide film from dehydration, depolymerisation and decomposition at the high-temperature stages.</p><p>Chemical Engineering Research Bulletin 19(2017) 80-86</p>

Value of subcutaneous fat in predicting ovulation day

Subcutaneous body fat and Quetelet's Indices (QI) of 52, 18-29 year old normal female volunteers were determined. These body mass indices were then grouped according to the phase of each subject's menstrual cycle, early or late follicular and early or late luteal phase. The subcutaneous body fat is 27.07 +or- 1.0% in the early follicular but drops to 24.68 +or- 1.84% in the late follicular phase. The value then rises significantly higher than that in the late follicular phase to 30.14 +or- 1.15% (P0.02) in the early luteal drops to 27.17 +or- 0.55% towards the level of the early follicular phase (P0.05). Variations in the values of QI during each menstrual cycle exactly mirror those for subcutaneous body fat. The fall in the 2 body mass indices during the late follicular phase coincides somewhat with the established preovulatory LH and FSH surges as well as the high levels of estrogen of this period. On the other hand the significant rise in the 2 parameters during the early luteal phase coincides with the marked rise in the ratio of progesterone to estrogen. Clearly, increased levels of progesterone relative to estrogen appear to cause an increase in the body fat during each menstrual cycle. The implication of this finding for women on contraceptive pills which are predominantly progesterone and those whose normal menstrual cycle is "interrupted" at the early luteal phase by a successful fertilization raises very interesting questions with regards to prediction of ovulation.