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Paper soap is currently in great demand by the public because it is easy to carry everywhere. In the process, solid soap is printed as thin as paper. This paper soap will dissolve and produce foam when exposed to water. This study aims to synthesize the paper soap product against the effect of variations in the concentration of polyvinyl alcohol (PVA). PVA serves as an adhesive and forms a thin layer (film). The raw material for making soap is virgin coconut oil and NaOH as a basic soap. Basic soap is mixed with glycerin, ethylene glycol, silicone oil, olive oil, aloe vera, and perfume. After that, the mixture was added with polyvinyl alcohol with various concentrations of 5, 10, 15, and 20 percent solution. The processed soap material is then poured into a flat mold with a thickness of 0.5 mm and 1 mm. The paper soap produced was tested for water content, free fatty acids, pH and antibacterial activity test. The test results showed that the best paper soap was obtained when using a 5 percent PVA solution. The results are in accordance with the requirements of SNI 3532:2016 solid soap with a moisture content of 12%, free fatty acids 1.5%, pH 9.6 and the value of inhibition diameter on the antibacterial activity test 18.7 mm, the value stability of foam of 94% with a thickness of 0.5 mm soap. [ABSTRACT FROM AUTHOR]

In this paper, the heat transfer enhancement of various nanofluids in a two-dimensional pipe are numerically studied. For nanofluid simulations, Eulerian–Eulerian, two-phase model is utilized, and the governing equations are solved using the finite volume method. Three distinct nanoparticles (Al2O3, CuO, and TiO2) and three base fluids (water, ethylene glycol, and turbine oil) has been investigated with 1% volume concentration. All nanofluids mixture have a constant inlet velocity. The heat transfer and the distribution of the wall temperature are presented in the comparison. The results report that Al2O3 −water nanofluid has the highest heat transfer enhancement performance among all the mixtures, then EG-Al2O3 and turbine oil-Al2O3, respectively. The temperature distribution on the pipe wall also reported the same finding. [ABSTRACT FROM AUTHOR]

This paper studies the experimental and numerical thermal performance of an evacuated tube solar collector (EVT) with a (PCM) integration at different working fluids. Two types of working fluid were used, the first working fluid is water and the second is ethylene glycol with a 30% percentage added to water. A two-dimensional numerical model is developed using ANSYS software program V.21. The results indicated that the addition of ethylene glycol with 30% percentage to the distilled water increased the evaporation temperature by 27% and improved the thermal properties. This improvement allows for an increase in the number of evacuated tubes in closed heating systems. [ABSTRACT FROM AUTHOR]

Cooling fluids are fluids that function to remove heat from certain object. In this paper, different cooling fluids were used to cool down the temperature of solar panel. The main objective is to investigate the effects of different type of working fluid on the cooling performance of the solar panel. The cooling fluids that have been used are water, ethylene glycol and mixture of ethylene glycol and water. These different cooling fluids will be used to determine the effects to the solar panel temperature, the power output of solar panel temperature and the efficiency of the cooling fluids on cooling performance. In this research work, the power output of the solar panel is the parameter that determines the cooling performance of working fluids. Longer cooling time of the solar panel shows a significant increase in solar panel power output. The findings revealed that the solar panel power output has achieved the highest efficiency at 8.18% when the water is introduced as cooling fluid compared to ethylene glycol at 3.18% efficiency and mixture of water and ethylene glycol at 1.91% efficiency. [ABSTRACT FROM AUTHOR]

One effective and efficient selection method to obtain initial information on drought-tolerant genotypes is to observe growth in the germination phase using PEG (Poly Ethylene Glycol). The purpose of this study was to examine the morphological response of Lampung local rice, Lumbung Sewu Cantik variety under PEG-induced drought stress in the germination stage. The concentrations of PEG given were 0%, 10%, and 20%. The research design was a completely randomized design with three replications. Observational data were analyzed for variance at the level a test = 0.05 and further analysis used Duncan's Multiple Range Test (DMRT). Observation of morphological responses showed that PEG induced water stress which affected the growth of Lumbung Sewu Cantik rice varieties during germination. Plumulae growth was inhibited because the concentration of PEG increased. However, the radicle root grew longer at 20% PEG. In addition, Lumbung Sewu Cantik can maintain the dry weight of the radicle and seminal root at increased PEG concentrations. [ABSTRACT FROM AUTHOR]

Nanofluid is a novel industrial fluid that has the potential to improve heat exchanger performance. This paper presents an experimental study on the forced convective heat transfer of a graphene oxide nanofluid composed of water/Ethylene glycol and various volume percentages of GO nanofluid (0.5–2) percent passing in a cylindrical shell and tube heat exchanger with various baffle angles. Counter flow is investigated in turbulent flow conditions. The influence of heat transfer rate, entropy development, and overall heat transfer coefficient in heat exchangers with various baffle angles. The above-stated factors of the heat exchanger were governed by conventional correlations using nanofluids. Among the different reformed baffle angles, cylindrical shape nanoparticles performed best in factors of heat transfer rate and overall heat transfer coefficient. The overall heat transfer coefficient of cylindrical shape particles with 120 baffle angle is found to be 15%, 24%, and 30% higher than 240, 360baffle angles, in consistent to 1.5 vol. percent of GO nanofluid. Heat transfer is also found to be greater for cylindrical shapes at 120baffle angle than for other baffle angles. Entropy development, on the other hand, decreases with increasing volume percentage for all baffle angles. [ABSTRACT FROM AUTHOR]

When lithium-ion battery is operating under high charge and discharge rates, there will be a rapid rise in the temperature of the battery. This high temperature of the battery will cause safety issues like thermal runaway and also will reduce the efficiency of the battery. In order to maintain the temperature of the battery within permissible limit, it is important to adopt thermal management system for batteries. There are several thermal management systems like air cooling, liquid cooling etc. But compared to all existing systems, liquid cooling system has greater efficiency in cooling the battery. In liquid cooling system, selecting right kind of coolant is important in order to cool the battery efficiently. In this paper, liquid cooling system of lithium ion battery is designed using "COMSOL Multiphysics Software" and simulated with two most commonly used coolants which are water and water-Glycol using "CFD ANALYSIS" in "ANSYS" and their heat transfer rates are calculated. [ABSTRACT FROM AUTHOR]

Epoxy is a thermoset material with excellent mechanical performance, dimensional stability, as well as thermal and chemical stability. This performance is influenced by the cross-linked structure of epoxy. Usually, the cross-linker used for epoxy is amine and anhydride-based material. Other materials such as poly(carboxylic acid) can also be used as a cross-linker. In this study, the use of combinations of amine-based and poly(carboxylic acid) cross-linker is reported. A modified citric acid (CA) was synthesized in this study by reacting CA with ethylene glycol (EG) at various molar ratios. This modified CA was then mixed with the epoxy with multiple weight ratios. Thermal analyses such as differential scanning calorimeter (DSC) and thermogravimetry analysis (TGA) show that the curing and decomposition temperatures of epoxy are influenced by the type of cross-linker used. Curing temperature of epoxy with modified CA is 164.44°C while with amine based cross-linker is 57.43°C. The thermal stability of epoxy cross-linked with modified CA is higher compared to the one with amine-based cross-linker. Increasing the EG content in modified CA can decrease the decomposition temperature of the epoxy. [ABSTRACT FROM AUTHOR]

In recent years, scientists have focused on improving the thermo-physical properties of a single component nanofluid. Hybrid or composite nanofluids are being developed to improve heat transfer performance. At various volume concentrations, the thermo-physical properties of Al2O3−TiO2−SiO2 nanoparticles suspended in water (W) and ethylene glycol (EG) blends with a volume ratio of 60:40 are investigated. The experiment was conducted at temperatures of 30, 40, 50, 60, and 70 °C with volume concentrations of 0.05, 0.1, 0.2, and 0.3% from Al2O3−TiO2−SiO2 nanofluids. The KD2 Pro Thermal Properties Analyzer is used to measure thermal conductivity and dynamic viscosity at temperatures ranging from 30 to 70 °Celsius of 0.3%, the increased thermal conductivity results in optimal conditions with more advantages for heat transfer than other concentrations. The highest thermal conductivity was obtained for tri-hybrid nanofluids at 0.3%, with a maximum increase of up to 9 percent over the base fluid (EG/W) mixture. Al2O3−TiO2−SiO2 nanofluids at 0.05% concentration have the lowest effective thermal conductivity of 4.8% at 70 C. At a concentration of 0.3%, the increased thermal conductivity results in optimal conditions, which have more advantages for heat transfer than other concentrations. [ABSTRACT FROM AUTHOR]

Three distinct polymers were used as model polymers in this study: poly (vinyl alcohol) (PVA), polyacrylamide (PAM), and poly (ethylene glycol) (PEG). These polymers were employed to make nanocomposites films utilizing solution and dry casting techniques with varied loading ratios of Silver nanopowders (AgNPs) of (0.1, 0.2, and 0.4 wt. percent). The films were of varying thicknesses (950 nm). The diffusion of NPs among the gaps of polymer mix particles was determined using optical microscopy (OM). The polymers and Silver nanopowders (AgNPs) created an important interfacial contact, as evidenced by Fourier-transform infrared spectra. In nanocomposites, the most functional group of polymer and nanoparticle. Using the ultrasound technique (U/S), the mechanical characteristics of each film were measured and estimated. The velocity of the U/S wave was calculated using the frequency (40 kHz) of the film thickness (950 nm). Except for compressibility, mechanical characteristics improved as the number of Ag NPs increased. Doping with AgNPs had a considerable impact on the U/S coefficients. The resulting blend gels demonstrate these new nanocomposites as potential materials for a wide range of applications, and they were used in medical applications instead of U/S sonar and echo gel. [ABSTRACT FROM AUTHOR]

Process Automation Systems are widely known to be a crucial element in processing plants worldwide. In an environment that is ever-changing, process automation is applied in industries when possible to mitigate complexities with advance process control (APC) systems specifically leading to higher efficiency, less operator interaction and increased profits. APC is a proven control and optimization technology delivering measurable and sustainable improvements in production yield, coupled with the added value of energy savings. Many researches focused on modelling the Ethylene glycol (EG) production process each with distinct reactors and reactions. On the other hand, the advances on its control system were poor. Thus, this research fills the gap on the implementation of APC for the EG reactor. In this work, a linear based model predictive control (LMPC) is developed and implemented in EG reactor. The aim of LMPC is to control the production rate and reactor temperature for an optimized hydrogenation reactor. The optimal set point used is based on multi-objective optimization approach using £-constraint method. A state-space model is used in the prediction control is constructed with the best fit of 91.51% and 83.34% for EG production rate and reactor temperature, respectively. The LMPC is developed in Simulink and tuned via the MPC design toolbox in Matlab. The LMPC performance was evaluated based on the analyses results obtained from set point tracking, disturbance rejection and robustness test. The results showed that the LMPC can operate efficiently under tight boundary constraint. This sums up that the LMPC can control both control variables under strict boundary conditions. [ABSTRACT FROM AUTHOR]

In order to intercede and understand the synergism between xylitol and glycols at varied temperature from 288.18 to 318.15 K, in (0.01, 0.02, and 0.03) mol·kg−1, the volumetric and acoustical parameters are being calculated from the experimental speed of sound and density. Using different values of the velocity of sound and glycol's denseness in an aqueous solution of xylitol at different values of temperature has been considered. Using the values of the velocity of sound, and density the adiabatic compression (β) and acoustic impedance(Z) were determined. The intermolecular free length (Lf), Wada's constant (W), Rao's constant (R), Vander Waal's constant (b) was determined using the experimental values. [ABSTRACT FROM AUTHOR]