Papers by Keyword: Lauric Acid

Abstract: A new form of composite PCMs is developed by adding 0.5 wt% of SiO₂, TiO₂, ZnO and CuO nanomaterials to lauric acid. Phase change temperatures of lauric acid range from 43.92°C to 44.65°C and 40.84°C to 41.36°C, respectively. In addition, the phase change latent heats are 183.23 kJ/kg and 183.68 kJ/kg at room temperature, respectively. Thermal properties of PCM with nanomaterials were discussed in terms of weight fractions. The improvement in thermal conductivity of the PCM owing to the dispersion of nanomaterials was verified by laser flash analyser (LFA). Hence, the newly developed composite PCMs holds great potential as a candidate for harnessing solar energy in low-temperature heating systems. Keywords: Phase Change Material (PCM), Melting, freezing, Nanomaterials and Lauric acid.

Abstract: Phase Change Materials (PCMs) have attracted growing attention recently in the renewable energy utilization and building energy efficiency due to their high capacity for storing thermal energy but their applications have been restricted by leakage, poor thermal conductivity, and high flammability. In this work, the flame retardant phase change material has been successfully prepared through integrating Resorcinol bis (diphenyl phosphate) (RDP) as a flame retardant into lauric acid (LA) as a phase change material. The DSC (differential scanning calorimeter) test is used to measure the thermal properties of LA_RDP. The thermogravimetric analysis (TGA) test demonstrates that the thermal stability of composite LA_RDP is improved. Cone calorimeter is applied to study the flammability properties of the flame retardant phase change material. As a result, the RDP-based flame-retardant PCMs developed could be used for safe and efficient solar energy storage applications.

Abstract: The use of energy storage materials in a solar distillation system is intended to increase condensate production by making changes in the temperature of the system change slowly, not following fluctuations in the intensity of solar radiation that can change quickly and drastically. One of the effective energy storage systems is the use of Phase Change Materials (PCMs), materials that involve a phase change process in storing and releasing heat, because the latent heat involved in the phase change process has a large enough value under constant temperature conditions so that temperature stability in the system is achieved. The choice of PCM type used in solar distillation is determined by the average temperature that can be reached by the water in the basin, which is strongly influenced by local environmental conditions. This study compares the productivity of the distillate produced by the double slope solar distillation system that uses Lauric Acid as PCM and that does not use PCM. Both studies were conducted at the same time. The optimal amount of LA that must be added to the solar distillation system to get the highest increase in condensate production value is 7.54 kg of Lauric Acid for 64.8 kg of raw water..

Abstract: The biocomposites were prepared from chitosan, carragenan and modified tapioca with lauric acid addition. The biocomposite were used as edible film material thus improving the mechanical characteristics. The purpose of this study was to determine the amount of lauric acid addition that produced biocomposites with the best characteristics. This study used experimental method. The different concentration of lauric acid used as the treatment was 0%, 10%, 20%, 30%, 40% from total solid of hydrocolloids materials (w/w). Data were analyzed statistically using the F test (ANOVA test) with confidence level of 95%. The results showed more than 10% addition of lauric acid decreased the value of moisture content, tensile strenght, percent elongation and water vapor transmission but increase thickness, opacity and transparency value. The addition of 10% lauric acid produced biocomposite with the best characteristics according to JIS (Japanese Industrial Standard) which had the moisture content of 42.65%, thickness of 0.047 mm, tensile strength of 13.8 MPa, percent elongation of 29.2%, water vapor transmission rate of 8.5 g/m²/day, opacity 8.9% and transparency 7.5. This research used renewable and biodegradable materials that can be applied to produce edible packaging with the best characteristics and eco-friendly.

Abstract: Water resistance of lauric acid (L) dissolved in biocompatible solvents mainly depended on the water affinity of solvent. L in DMSO (DL) was most sensitive to water and higher than L in N-methyl pyrrolidone (NL) and L in 2-pyrolidone (PL), respectively. From scanning electron microscope, differential scanning calorimetry, thermogravimetric analysis, powder x-ray diffractometry and hot stage microscope tests revealed the alteration of L crystal owing to the interference by solvent during precipitation. All L precipitates had lower melting point and degradation temperature than intact L in which L precipitated from 2-pyrrolidone exhibited the lowest melting temperature. These characteristics will be useful for modifying L in phase inversion in situ forming gel.

Abstract: Synthesis of glucose laurate (GLC12), fructose laurate (FRU12), and galactose laurate (GAL12) as antibacterial and antifungal agents has been carried out. The synthesis of GLC12, FRU12, and GAL12was conducted by reacting lauroyl chloride with glucose, fructose, and galactose in the presence of pyridine in 36.1; 77.8; and 72,2% yields respectively for GLC12, FRU12 and GAL12.Antibacterial and antifungal activity test was done using well diffusion method towards Gram-negative bacteria (Salmonella thypimurium and Escherechia coli), Gram-positive bacteria (Staphylococcus aureus and Bacillussubtilis), Candida albicans fungus, DMSO as a negative control, and 4-isopropyl-3-methylphenol 1% as a positive control. The best antibacterial activity was shown by FRU12at 12.5% of concentration against S.aureusand B.subtilis bacteria.

Abstract: Pyrrole was successfully polymerized on copper surface in ethanol solution using hydrogen peroxide as catalyst to generate an adherent and homogeneous polypyrrole (PPy) coating. The PPy was formed of clusters composed of small spherical grains. The layer has remained stable when immersed in 0.1mol L^-1 NaCl for 7 days, which indicated that the copper-PPy arrangement is stable in corrosive environment. The polarisation curves showed that the PPy layer can promote a positive displacement in the corrosion potential compared to the value of the uncoated copper. It also was observed that the corrosion current density decreases sharply in the presence of the lauric acid as dopant. These results indicate that PPy-lauric acid can act as a protective layer on copper and improve the overall corrosion performance.

Abstract: The building energy conservation has an important role in the energy field. Lightweight materials have been extensively used. By compositing the capric acid (CA) and lauric acid (LA) eutectic and using the expanded perlite (EP) as the matrix, a phase change material (PCM) was prepared and studied in laboratory. The mass fraction of this PCM reached at 60% through direct immersion for 24 hours. Differential scanning calorimeter (DSC) testing results indicated that the melting temperature of the PCM is 18.0°C, and the latent heat is 73.77J/g. From 1000 times cycling and heat-release characteristic test, this PCM was found to be stable well. After 2(wt)% graphite added in, solidification time of the PCM decreased by some 30%, the thermal conductivity improved. Application showed that the PCM has a positive effect on improving indoor environmental temperature.

Abstract: Guided Bone Regeneration (GBR) membrane is used as a barrier to prevent soft tissue ingrowth and to encourage bone regeneration through cellular exclusion. This study aims to assess antibacterial properties of recently developed three-layered poly(lactic-co-glycolic acid) (PLGA) /lauric acid (LA) composite membrane towards Staphylococcus aureus. One of the outmost layers of three-layered membrane was incorporated with 1-3 wt% of LA. The composite membrane was developed using thermally induced phase separation/solvent leaching technique. SEM results shows formation of PLGA matrix with smaller pores by the addition of 1 wt% LA compared with pure PLGA membrane. Samples of 1.7 cm diameter disk containing 1, 2 and 3 wt% of lauric acid were tested and pure membrane without lauric acid was used as a control. Results showed that the zones of inhibition were 2.3 cm and 2.5 cm for the 2 wt% and 3 wt% LA-containing membranes, respectively. However, 1 wt% LA-containing membrane observed to have no inhibition at all, indicating that increasing concentration of LA has significant inhibition against Staphylococcus aureus. The 3 wt% LA composition will be used in the mechanically optimized membranes for degradation studies in future works.

Abstract: With the global warming, phase change materials are being expected to be applied in asphalt pavement to help lower its surface temperature. In this study, a kind of composite phase change material was prepared and its technique parameters were optimized through theoretical analysis and experimental study. A solid-liquid phase change material, with melt point of 43°C and phase transition heat of 161.6J/g, was used as core. The organophilic montmorillonite (OMMT) was used as a carrier and can prevent leakage of the melted phase change materials. The results showed that the ratio of OMMT to lauric acid was 2.6:1, and the melting temperature and time were 74°Cand 1.5hours, respectively. The composite phase change material prepared in this study had the phase transition latent heat of 36.168J/g and the transition temperature of 40.094°C. And the experimental results are in good agreement with theoretical analysis.