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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]

This paper focuses on an experimental investigation on the dispersion stability of 60:40 water and ethylene glycol based Al2O3−CuO hybrid nanofluids. The volume and concentration of hybrid nanofluids were set to be 30 ml and 0.5%. Three different surfactants (PVP, CTAB, and SLS) with different surfactant ratios (1:10 and 5:10) were used to ensure the nanofluids remained homogenous for a longer period. Dispersion stability is studied using several methods such as sedimentation observation, zeta potential, and UV-Vis. FESEM testing is conducted to study the morphological behavior of the nanoparticles powder, including particle size and structure. Visual inspection showed that only pure Al2O3-CuO and Al2O3-CuO-PVP (1:10) remained homogenous without any visible separation layer. As for UV-Vis spectroscopy, the absorbance value for all samples was below than 1%. Thus, to further investigate the stability Al2O3-CuO hybrid nanofluid, the Zeta potential test is also conducted. Analysis of Zeta potential indicated that PVP with surfactant ratio 1:10 provided better result on the nanofluid stability. The pH value for sample with the PVP dispersant is then measured to be 7.7 which is slightly further from the IEP (pH 9.7-10) [ABSTRACT FROM AUTHOR]

In this paper an evolution model constructed to step up the collector efficiency. Experiments are conducted on fabricated Parabolic solar thermal collector (PSC) by telling three different absorber tubes (Copper tube coated with Ni-Al, vacuum tube and Nano fluid tube) and three heat transfer fluids (water, Ethylene Glycol +Water(60:40) and copper oxide Nano particles Nano fluid)one at each time. The setup was installed on SVU College of engineering building at Tirupati of 13.6288° N latitude and 79.4192° E longitude. In experimentation, heat transfer fluid temperature was collected at every one hour gap. With help of this temperature and incident radiation on aperture area, the maximum and minimum efficiencies of collector are evaluated in a day. Analysis is done on experimental results by using Factorial method and ANOVA. The optimized combinations are identified. Here Simulation is done for the purpose of judging the utilization of resources, hence the Optimized combinations of heat absorber tubes and Heat transfer fluids are used in Simulink of Mat lab. Finally observed that fabricated model of solar thermal collector has had improved efficiency. [ABSTRACT FROM AUTHOR]

This paper presents an extensive numerical work on the thermo acoustical properties of CuO nano-particles contained aqueous solutions of ethylene-, propylene- and hexylene- glycols. Several thermo-acoustical parameters such as Moelwyn-Hughes parameter, reduced volume, reduced compressibility, Sharma’s constants, Huggins parameter, isobaric, isochoric, and isothermal acoustical parameters, fractional free volume, repulsive exponent etc, have been evaluated using the data available in the literature. The variation of these parameters has also been investigated within the temperature range 303.15K-313.15K. Using four different approaches, a comparative study of non-linearity parameter, B/A, has also been done. The present analysis provides a deep insight into the nature, type and strength of particle-particle and particlefluid interactions prevalent in the systems under study. [ABSTRACT FROM AUTHOR]

Palladium nanoparticles were synthesized by reducing sodium tetrachloropalladate at 100oC using Ethylene Glycol as reducing agent. The nanoparticles were characterized by TEM (Transmission Electron Microscopy), and optical absorption spectroscopy. The average particle size (<10 nm) was obtained from TEM images, and the palladium SPR (Surface Plasmon Resonance) absorption maxima was observed at ~220 nm. The porous sensing films were prepared by drying the nanoparticles precipitate on cleaned glass substrates. The high porosity of these films, as revealed by Atomic Force Microscopy (AFM) studies, made these films suitable for hydrogen sensor applications. The resistance of the films, measured by making silver paste contacts on the porous surface, changed upon exposure to 1000 ppm hydrogen in nitrogen. Optimum sensor response was obtained at 50°C, beyond which it deteriorated. The total response comprising of initial rise and subsequent fall in resistance, is due to the formation of Pd-hydrides (whose resistivity is higher relative to Pd), and closure of interparticle gaps due to lattice expansion of palladium, respectively. A detailed analysis of the results based on the sensing mechanism has been discussed in the paper. [ABSTRACT FROM AUTHOR]

In this paper, carbon dots were synthesized from glucose, soot and ethylene glycol by hydrothermal treatment. The resulting carbon dots were characterized by luminescent spectrometry and spectrophotometry. The spectra exhibit bright luminescence in the blue region and strong absorption in the ultraviolet region. All samples exhibit typical excitation wavelengthdependent properties. [ABSTRACT FROM AUTHOR]

Nanofluids can be considered to be the next-generation heat transfer fluids as they offer exciting new possibilities to enhance heat transfer performance compared to pure liquids. In this paper preparation of Ethylene Glycol (EG) based graphite nanofluid by two step method using PVP as surfactant is studied. Four different volume concentrations of 0.05%, 0.2%, 0.86% and 2% nanoparticles are suspended in the EG base fluid by ultrasonication for 5 hours. The effect of shear rate from 10-100s-1 on viscosity of nanofluid is performed at a fixed temperature. The nanoparticle size considered for analysis of viscosity is <50nm. Further, the thermal conductivity of prepared nanofluid is estimated at a constant temperature for nanoparticle size of <50nm and <100nm. From this complete investigation it is concluded that the viscosity of nanofluid increased with change in volume concentration. Thermal conductivity ratio has shown a linear improvement with increasing volume concentration of nanoparticle. Particle size shows an influence on thermal conductivity variation along with volume concentration. [ABSTRACT FROM AUTHOR]

Nanostructured ceramic materials have recently attracted attention as promising heat transfer fluid additives owing to their outstanding heat storage capacities. In this paper, experimental measurements of the specific heats of SiO2-Glycerol, SiO2-Ethylene Glycol, and SiO2-Glycerol/Ethylene Glycol mixture 60:40 ratio (by mass) nanofluids with different volume concentrations of 1.0-4.0% have been carried out using differential scanning calorimeter at temperatures of 25°C and 50°C. Experimental results indicate lower specific heat capacities are found with SiO2 nanofluids compared to their respective base fluids. The specific heat was decreasing with the increase of concentration, and this decrement depends on upon the type of the base fluid. It is observed that temperature has a positive impact on the specific heat capacity. Furthermore, the experimental values were compared with the theoretical model predictions, and a satisfactory agreement was established. [ABSTRACT FROM AUTHOR]

This paper addresses free convection in cavity filled with ethylene glycol(EG) nanofluid containing Fe3O4 in the presence of radiation. Galerkin's method of finite elements is employed to solve the governing differential equations. Numerical results are computed for certain pertinent parameters: Rayleigh number (10-2500), radiation parameter (1-10) and nanofluid volume fraction (0-0.3), and presented in the graphical form. The results reveal that flow intensity and heat transfer rate in EG-Fe3O4 nanofluid are increasing functions of Rayleigh number and radiation. It is noted that high Rayleigh number and radiation are needed to affect flow intensity. [ABSTRACT FROM AUTHOR]

In this research, the synthesis of molecularly imprinted polymer (MIP), Polyeugenol was used as a base polymer with EGDMA as the crosslinker. This research aims to produce a urea selective adsorbent. Polyeugenol produced from eugenol was bind with urea templates and cross-linked with EGDMA in a chloroform solvent and initiator 2, 2' azo-bis (2-methylpropionitril) (AIBN) producing a MIP. A non imprinted polymer (NIP) is also used in this study for comparison. Analysis of polymers and adsorbent characterized by FTIR spectrophotometer and SEM followed by adsorption test. MIP has higher adsorption results than the NIP. Besides, the size of urea, creatinine and vitamin B12 also affects the adsorption process. MIP and NIP adsorbent have adsorption percentages of urea > creatinine > vitamin B12 which are 32.51, 26.17, and 2.85% for MIP and 15.70, 9.40 and 1.90% for NIP respectively. [ABSTRACT FROM AUTHOR]

Continuous technological development in automotive industries has increased the demand for high efficiency engines. Optimizing design and size of a radiator in order to reduce a vehicle weight is a requirement for making the world green. Using of fins is one of the techniques to increase the cooling rate of the radiator. However, traditional approach of enhancing the cooling rate by using fins and microchannels has already showed to their limit. Furthermore, heat transfer fluids such as water and ethylene glycol have very low thermal conductivity. As result there is an urgency for new and innovative heat transfer fluids for increasing heat transfer rate in an automotive cooling circuit. Nanofluids represent potential substitute of conventional coolants in engine cooling system. In this paper a cooling circuit is modelled in TRNSYS (version 17) and investigated in transient regime. The circuit is composed by a heating system, a pump and a heat exchanger. The heat exchanger represents a car radiator in the circuit. The nanofluid is a mixture of water and Al2O3 nanoparticles. The study is conducted for three different engine operating conditions (Low, Medium and High) and different volume concentrations of nanoparticles. [ABSTRACT FROM AUTHOR]

In this paper, numerical investigation using ethylene glycol (EG) as a base fluid with diamond and SiO2 as the coolants with nanoparticle volume fractions (φ) ranged from 0.1 % to 2 % on automobile flat tube plain fin compact heat exchanger (CHE) is conducted. The convective heat transfer coefficient in the developing regions along the flat tubes with the nanofluid flow showed marked improvement over the base fluid (0 %). Quantitative results of the heat transfer enhancement of CHE with increasing volumetric concentrations of nanofluids at various Reynolds numbers are presented. [ABSTRACT FROM AUTHOR]

This paper is about the nanocellulose with water and Ethylene Glycol for car radiator application. The research is conducted in order to prove that addition of nanocellulose from plant with varying concentration provides a better heat transfer efficiency compared to usage of distilled water as radiator coolant. The objective of the research is to analysis the performance of vehicle radiator using one-dimensional analysis based on collaboration of nanocellulose with readily available coolants which is Ethylene Glycol. The scopes of the research are the nanoparticles used in the experiment is nanocellulose between ranges of size 40-80 nm. The tested concentration of the cellulose nanofluids are as of 0.5%. Based on the nanocellulose properties, the performance characteristics of a radiator running with water and Ethylene Glycol were investigated using the one-dimensional numerical analysis method of one dimensional software. Radiator model was drawn and the results of the analysis is compared. The radiator model was developed corresponding to a real model of radiator. The radiator was simulated to study the characteristic of radiator performance when the radiator is operating with nanocellulose. The simulation results showed that the temperature decreases with the increasing in volume concentration. Furthermore, the heat transfer coefficient and effectiveness increases with increasing in percentage of nanocellulose. [ABSTRACT FROM AUTHOR]

In this paper, we present thermal conductivity and thermal diffusivity of chromium (Cr) nanoparticle suspended in ethylene glycol at different volume fraction concentrations of nanoparticle. All samples have been prepared using single step method. The thermal conductivity and thermal diffusivity were measured via hot wire-laser beam deflection method. A numerical simulation of the heat conduction equation and probe beam deflection has been performed to determine the effective thermal conductivity and effective thermal diffusivity of Cr nanofluids. By fitting the experimental data to the numerical data, the thermal conductivity and thermal diffusivity of chromium (Cr)-ethylene glycol was obtained. The results also show that the effective thermal conductivity and thermal diffusivity of nanofluids increases with the increasing of nanoparticle volume fraction concentration in base fluid. [ABSTRACT FROM AUTHOR]

In this paper we study and monitoring the drinking waters with Quartz Crystal Microbalance (QCM) versus Atomic Absorption Spectrometry (AAS) and classical analytical methods (pH, conductivity/resistivity, TDS, salinity). Our studies present a new application of quartz crystal microbalance (QCM) for measure and identify trace quantities of metals and volatile organic compounds (VOC) in water. QCM was adapted for many different uses by developing electrodes that respond to different target molecules. For our experiences we use quartz crystal sensor with 1.25 cm2 sensitive area at 5 MHz resonance frequency and CrAu electrode (20 nm Cr and 200 nm Au).We monitoring in real time the quality of water by controlling the inorganic and organic impurities. We evaluate the utility of QCM sensors to detect a range of VOC contaminant which is complementary with AAS. Some polar VOC contaminants were tested: acetone, isopropanol and ethylene glycol. [ABSTRACT FROM AUTHOR]

The compaction of powders into tablets is widely used in several industries (cosmetics, food, pharmaceutics...). In all these industries, the composition of the initial powder is complex, and the behaviour under compaction is not well known, also the mechanical behaviour of the tablets. The aim of this paper is to understand the behaviour (pressure vs density) of a simplified media made of fragile and ductile powders, varying the relative ratio of each powder. Some compaction experiments were carried out with glass beads (fragile) and Polyethylen Glycol powder (ductile). We observe two typical behaviours, depending on the relative volumic fraction of each component. A transition is pointed out, observing the evolution of the slope of the curve pressure/density. This transition is explained by geometrical considerations during compaction. A model is proposed, based on the assumption that the studied media can be compare to a diphasic material with a continuous phase (the ductile powder) and a discrete phase (the fragile powder). The result of this model is compare to the experimental results of compaction, and give a good prediction of the behaviour of the different mixing, knowing the behaviour of the ductile and the fragile phase separately. These results were also interpreted in terms of Heckel parameter which characterizes the ability of the powder to deform plastically under compaction. Some mechanical tests were also performed to compare the mechanical resitance of the obtained tablets. [ABSTRACT FROM AUTHOR]

This paper presents measurements of specific heat and density of aluminum oxide (Al2O3) nanoparticles suspended in 60:40 (by mass) ethylene glycol and water mixture (EG/W). These property values are necessary to determine the fluid dynamic and heat transfer characteristics of nanofluids. These properties have been measured over a range of temperatures for nanoparticle volumetric concentrations of 0 to 10%. From the experimental results, empirical correlations have been developed as a function of temperature and particle volume concentration. These correlations will be valuable in studying the heat transfer performance and the pumping power requirement of Al2O3 nanofluid in various applications such as industrial heat exchangers, building heating and automotive cooling. [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]

The preparation of stable, uniform silver nanoparticles by reduction of silver acetate by ethylene glycol (EG) is reported in the present paper. It is a simple process of recent interest for obtaining silver nanoparticles. The samples were characterized by X-Ray diffraction (XRD), which reveals an average particle size (D) of 38 nm. The UV/Vis spectra show that an absorption peak, occurring due to surface plasmon resonance (SPR), exists at 319 nm. [ABSTRACT FROM AUTHOR]

A study of the kinetic formation of silver-copper nanoparticles in aqueous medium on the basis of size distribution and its characterization has been carried out and reported in this paper. The Ag-Cu nanoparticles were synthesized through polyol method that using Ethylene Glycol (H2C6O12) as a reduction agent and solvent and Polyoxyethylene-(80)-Sorbitan Monooleate (Tween 80) as a stabilizer. The kinetic formation of Ag-Cu nanoparticles was observed using Dynamic Light Scattering (DLS) and characterized by using X-ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM) and Transmission Electron Microscope (TEM). The XRD analysis results confirmed that size distribution was strongly dependent on molarity of precursors of silver (AgNO3) and copper (Cu(NO3)2.3H2O). The FESEM and TEM analysis indicated the existence of Ag and Cu nanoparticles in the core-shell shape. The silver-copper nanoparticles were spherical and uniform particles size with the average size of about 28 nm and 38 nm for silver and copper, respectively. DLS observation showed the growth of nanoparticles at the temperature of 140°C as the effect of reaction time at 1, 2, 3, 4 and 5 hours. [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]

This paper describes the basic factors affecting the stability of the foam films produced in the presence of nonionic surfactants such as n-pentanol, n-octanol, methyl isobutyl carbinol (MIBC), and polypropylene glycol (PPG). We used a model developed by Wang and Yoon (Colloids and Surfaces A: Physicochem. Eng. Aspects 282–283, 84–91 (2006)) to calculate the Gibbs elasticity of the lamellae films. In addition, we used the thin film pressure balance (TFPB) technique to measure film thicknesses. The results were used to determine the disjoining pressures in the thin lamellae (foam) films formed between air bubbles, which are relevant forces governing the final drainage stage of foam films before reaching either equilibrium or rupture. The film elasticity and surface forces data were then compared with the foam stabilities measured in the present work in the presence of the various surfactants. It was found that foam stabilities are controlled both by film elasticity and by surface forces, the relative contributions of each changing with surfactant type and concentration. In general, surface forces play a more important role at relatively low surfactant concentrations, while elasticity plays a more important role at higher concentrations. At the surfactant additions usually employed in the mining industry, MIBC stabilizes foams by increasing disjoining pressures, while PPG-400 stabilizes foams by increasing film elasticity. [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]

The front photopyroelectric (FPPE) configuration, together with the thermal-wave resonator cavity (TWRC) method was applied in order to measure both thermal effusivity and diffusivity of liquids. The methodology is based on a 4-layer detection cell (pyroelectric sensor, coupling fluid, solid separator and liquid backing) in which the investigated liquid is inserted successively in backing and in coupling fluid's position, respectively. In such a way the FPPE-TWRC method becomes self-consistent; all static and dynamic thermal parameters can be derived with the same technique (two of them are directly measured and the remaining two calculated). The suitability of the method was demonstrated with investigations on several liquids as: ethylene glycol, glycerine, silicon and mineral oils. [ABSTRACT FROM AUTHOR]

Ru nanoparticles supported Al2O3 with uniform particle size have been synthesized by using conventional microwave oven in three different powers. RuCl3.nH2O, ethylene glycol, polyvinyl pyrolidone (PVP) were used as metal precursor, solvent and stabilizing agent, respectively. Beside irradiation power, effect of PVP and preparation route were also studied in this paper. The samples were characterized by UV-Vis, XRD, Small Angle X-Ray Scattering (SAXS), and TEM. The XRD pattern of Ru/Al2O3 catalysts did not show noticeable difference among each other. The powders were then analyzed further by SAXS technique. TEM image confirmed the nanosized (about 2 nm in average) of colloidal and supported ruthenium that obtained in all irradiation power. Ruthenium nanoparticles were also uniformly distributed over the support. The surface fractal distribution of ruthenium nanoparticles was examined by using SAXS. The irradiation power and the addition of PVP are strongly correlated with the surface fractal distribution of the nanoparticle. [ABSTRACT FROM AUTHOR]

Colloidal crystals (CCs) are made up of sub-micron sized charged particles dispersed in a deionized polar medium and exhibit body centered cubic/face centered cubic structure depending on the volume fraction. The dynamics of colloidal crystals differ from that of atomic crystals due to the presence of viscous fluid. The fluid causes friction which strongly dampens the motion. The lattice dynamics of CCs with hydrodynamic interactions predict that all the modes are over-damped except the long wavelength transverse modes, which are predicted to be propagative. This prediction of hydrodynamic theory of charged CCs remained elusive to dynamic light scattering measurements for a long time because of thin samples (thickness ∼30–130μm) of CCs. Dilute CCs grown in thin cells were used in the past to minimize the multiple scattering of light. Apart from reviewing these studies of phonon dispersion measurements, recent results on multiple scattering free large size (∼3mm) CC’s of silica dispersed in 90:10 ethylene glycol-water mixture (EGW) are discussed in this paper. At variance with the reports of phonon dispersion measurements on thin CCs, the measurements on millimeter-sized crystals show unambiguous evidence for overdamped transverse modes turning propagative in the range of small wave numbers in qualitative agreement with the theory of hydrodynamic interactions in charged CCs. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Nanofluids have emerged as a major area of research due to significant increase found in their thermal conductivity compared to the base fluids like Water, Ethylene Glycol, Toluene, etc. The enhanced transport properties of nanofluids and heat transfer efficiency have given them an edge over micro to macro sized particle suspensions. These fluids find great applications in thermal management as industrial coolants and various biomedical applications including cancer therapy. Major mechanism appears to be layering of liquid molecules at the solid-particle surface to form an interfacial nanolayer. This paper describes the dependence of effective thermal conductivity of nanofluids on nanoparticle concentration and transport properties of interfacial layer. We have studied the role of interfacial layer and nanoparticle Al2O3 concentration to the effective thermal conductivity of Al2O3/Water based nanofluid. Effect of temperature and pressure has also been investigated. Estimated values are found to match excellently with the available experimental data. [ABSTRACT FROM AUTHOR]

Cardiovascular disease is the leading cause of death globally. Cardiovascular diseases such as coronary arteries, strokes and peripheral arterial disease involve atherosclerosis, a condition in which the inside of the arteries narrows due to plaque buildup. One of the cause of atherosclerosis is high blood pressure. Nifedipine is a drug used in the treatment of cardiovascular disease caused by hypertension. Nifedipine is a high blood pressure-lowering drug that is insoluble in water and has low bioavailability. It is consumed 3 times a day. Consumption of drugs that are done repeatedly will increase the side effects of the drugs. Therefore a controlled drug delivery system is needed to increase the bioavailability of the drug. Microencapsulation method using biodegradable polymers is an alternative choice to achieve it. In this study, two types of biodegradable polymers poly(L-Lactic Acid) (PLLA) and poly(Ethylene Glycol) (PEG) were selected as coating materials for the encapsulation of nifedipine. Surfactants Tween 80 and Span 80 were also used in the formation of microcapsules to increase its stability. Based on the optimization of PLLA:PEG poly blend composition, the best results were obtained, which is 60:40 (w/w), with percent encapsulation efficiency and percent drug release of 72.68% and 18.17% respectively. The low dissolution result compared to the commercial nifedipine is caused by several factors including the relatively high crystallinity of PLLA so that it strongly coats nifedipine and the role of PEG as pore opening agent which is not optimal. These results were supported by X-Ray Diffraction (XRD) analysis and Scanning Electron Microscope (SEM) to observe the morphology of microcapsules. [ABSTRACT FROM AUTHOR]

Adding small amount of graphene oxide (GO) into heat transfer fluids has been found to enhance thermophysical properties of the fluids. Nevertheless, the efficiency a GO-based nanofluid for heat transfer application is depending on ability of the GO to stay disperse in the base fluid. Realizing this, the present study investigated the long-term colloidal stability (up to 2 days) of GO upon added into different types of commonly used heat transfer fluids. Results showed that GO can be dispersed in distilled water, ethylene glycol, propylene glycol, and ethanol upon subjected to sonication. However, rapid agglomeration and sedimentation of the GO in ethanol medium rendering it a less effective heat transfer nanofluid. On the other hand, GO nanoparticles were observed to be highly stable in both ethylene glycol and propylene glycol, possibly due to protic nature of these two base fluids. In fact, the GO nanoparticles were found to be ~100 % and > 82 % stable in ethylene glycol and propylene glycol-rich medium, respectively; a condition much better than the one dispersed in distilled water medium. Interestingly, it was found that the GO failed to disperse in engine oil which made up of non-polar hydrocarbon chain, hence, suggested its poor compatibility with this type of heat transfer fluid. It is envisaged that outcome from the present work can provide a proper guideline on the selection of suitable fluid for making GO-based heat transfer fluid. [ABSTRACT FROM AUTHOR]

Nanofluids are the nanoparticles suspension in fluids which have unique characteristics such as a low viscosity and high thermal conductivity that helps to enhance the heat transfer rate in thermal systems. Present study deals with the preparation of various nanoparticles with base fluids (DDW and DDW-EG mixtures) in the ratio of 50:50 and 70:30 at different concentration ranges from 0.1-5% by volume. Nanofluids are prepared by using direct dispersion method and then 80 min sonication time was observing as optimized time on the basis of thermal conductivity behaviour of nanofluids. Experimental findings confirm that the thermal conductivity of nanofluids rise significantly with subsequently rise in ratio of ethylene glycol in water, with increase in nanoparticles volumetric concentration and temperature. Carbon nanotubes with water:EG (50:50) show maximum enhancement of 40% for 5% nanoparticle concentration at 50 °C. [ABSTRACT FROM AUTHOR]

In recent years, problems connected with the enhancement of heat transfer have come to the forefront of thermophysical research. One of the current approaches to this problem consists in the search for partially-soluble additives to the liquid heat carrier combined with an optimisation of the thermal conditions in which these additives provide a significant effect. In this report, the thermal response characteristics of a solution of water and polypropylene glycol (PPG-425), having a lower critical solution temperature (LCST), used to facilitate powerful heat dissipation, are discussed. The method of controlled pulse heating of a wire probe was applied. An analysis of the energy values transferred from the probe to the solution in a particular heat release mode showed that, for a solution with 20-30% content of PPG, these values exceed the corresponding values for pure water by an order of magnitude. This result can serve as a basis for the search of a new generation of coolants for processes in which powerful heat generation is possible. [ABSTRACT FROM AUTHOR]

Shape memory polymer of poly (lactic acid) (PLA) has attracted a significant attention, especially in the field of biomedical application. This is mainly because of its biocompatibility rendering it safe to use in human body. The glass transition temperature (Tg) of PLA is used as a mechanism to activate the shape memory effect. Nonetheless, utilization of PLA in medical application is limited due to its brittleness and relatively high Tg (about 60°C). In this work, poly (ethylene glycol) (PEG) with molecular weight of 4,000 g/mol was used as a plasticizer for PLA. Effect of PEG contents (10, 15, 20, 30, and 40 wt%) on thermal and mechanical properties were investigated by differential scanning calorimetry (DSC) and tensile test, respectively. Furthermore, influence of PEG on shape recovery ratio was investigated at a constant temperature of 65°C. It was found that tensile strength, tensile modulus, and Tg values of the plasticized PLA decreased, while elongation at break increased with the increasing PEG content. The shape recovery of plasticized PLA was slightly decreased as PEG content increased. In order to enhance the shape memory performance of PLA blends, montmorillonite (MMT) nanoparticles were added into the plasticized PLA. Nanocomposites of plasticized PLA with 20 wt% PEG (20PEG/PLA) were prepared with the filler loadings of 1 and 3 phr. The exfoliation of MMT in polymer matrix was confirmed with the observation of a peak position angle of MMT via X-ray diffraction (XRD). The presence of MMT in 20PEG/PLA was found to increase the tensile modulus and shape recovery ratio over those of 20PEG/PLA. In this work, we have illustrated that shape memory performance of PLA can be enhanced by the incorporations of PEG and MMT. [ABSTRACT FROM AUTHOR]

Solid waste of Spent Bleaching Earth (SBE) containing a small amount of oil is generated in the processing Crude Palm Oil (CPO) into cooking oil. Recovery of the oil from SBE from extraction process can produce SBEO (spent bleaching oil), a low-grade oil which has dark color, contain significant amount of FFA (free fatty acid) and solidified at ambient temperature. In this research, this SBEO is utilized as biolubricant after treating through 2 step of processes. The first step is the conversion of SBEO into methyl ester by decolorization, FFA reduction, and transesterification processes. The second step is conversion of methyl ester into ethylene glycol ester. Transesterification of the SBE into methyl ester by methanol at ratio 1:6, give yield of 99.74. While second step transesterification of methyl ester into ethylene glycol is conducted by ethylene glycol. Temperature of 170°C has the best result of yield (93%). Physical characteristic of the ethylene glycol product give density at 40°C of 0.91 gr/cm3 and viscosity (at 40°C) of 9,75 cSt, flash point of 252°C, pour point of -7°C. This Physical characteristic meet the standard SNI 7069.9-2016 for hydraulic lubricant [ABSTRACT FROM AUTHOR]

Complex dielectric spectra over the frequency range of 10 MHz to 20 GHz and FTIR spectra in the region of 4000 cm−1 500 cm−1 of binary mixture of ethylene glycol monobutyl ether with methanol were obtained over entire concentration range at 303K. The static dielectric constant (ε0) and relaxation time (τ) have been obtained. Using these values the excess permittivity (εE), excess inverse relaxation time (1/τ)E, and Kirkwood correlation factor (geff) were determined. On the basis of these parameters, intermolecular interaction and dynamics of molecules are predicated and conformational of the hydrogen bond is supported by the FTIR. [ABSTRACT FROM AUTHOR]

Solid phase extraction is a preferable separation technique since it offers many advantages such as simple, good stability and can be regenerated over time. Due to presence of contaminant in the matrix, pre-concentration must be conducted using selective sorbent. Ion imprinted polymer (IIP) has remarkable selectivity and affinity towards the ion target due to its specific cavity during the imprinting process. In this study, Fe(III)-IIP was successfully synthesized by applying iron (template) with gallic acid (ligand) in acetonitrile and copolymerized using methyl methacrylate (functional monomer) and ethylene glycol dimethyl acrylate (EGDMA) as a crosslinker in the presence of azo-bis-isobutyronitrile (AIBN) as initiator. Fe(III)-IIP was characterized using FTIR, SEM-EDX, and TGA. Optimization of Fe(III)-IIP synthesis was carried out by varying the mole ratio of monomer to template (1:1, 2:1, and 3:1). Adsorption test exhibited the optimum ratio of 2:1 with the maximum adsorption capacity of 122.264 mg/g at pH 5 for 60 minutes contact time. The adsorption mechanism followed Freundlich equation with R² 0.9781. Relative selectivity of Fe(III)/Cr(III) and Fe(III)/Ag(I) were 3.41 and 0.707, respectively. The IIP was further tested for preconcentration of Fe(III) in lake water sample and obtained the % recovery value 102.02 %, 97.04 %, dan 96.61 %. IIP was successfully applied for iron preconcentration in water samples. [ABSTRACT FROM AUTHOR]

The Ionic imprinted polymer (IIP) Au (III) adsorbent has been synthesized using polyeugenol as a base polymer with ethylene glycol dimethacrylate (EGDMA) as a crosslinking agent to adsorb Au (III) metal ions from water media. The synthesis procedure includes polymerization, binding of mold ions, crosslinking and mold ions release. As a comparison, the non-imprinted polymer (NIP) material was also synthesized. The polymer yielded was characterized using FTIR, SEM-EDX, and TGA-DTA and then continued with adsorption. Selective adsorption was tested for a mixture of Au (III) binary metal ions with Cd (II), Pb (II) and Fe (III). The adsorption mechanism of Au (III) in all adsorbents is dominant because of the coordination bond between the -OH group and the Au (III) hydrate. Adsorption capacity is expressed as a percentage of IIP-Au (III) of 99.88% over the capacity of other adsorbents; IIP-Au (III) is more selective than NIP with successive selectivity coefficients of Fe (III) 263.03,Cd (II) 53.18, and Pb (II) 6.06. [ABSTRACT FROM AUTHOR]

Silver nanoparticle has excellent antibacterial activity. For human treatment, it is necessary to optimize the activity as well as to prepare it as a biocompatible and safe compound. In this report, we use a combination of silver nanoparticle (AgNPs) and magnetite Fe3O4 nanoparticles (MNPs) which are encapsulated using polyethylene glycol (PEG). We report detail the influence of AgNPs on crystal structure, absorbance, and antibacterial activity of Ag-Fe3O4@PEG. The structure of the system has been characterized using FT-IR to obtain its functional group's bonds, XRD to obtain its crystal structure and its grain size, and SEM to achieve its morphology. The absorbance of Ag-Fe3O4@PEG was characterized using UV-Vis, while antibacterial activity was tested using diffusion method. It was shown that the introduction of AgNPs changes the functional bonds of the system. There is no significant change in the lattice parameter value. It means that the AgNPs, MNPs, and PEG appear as a composite system. We found that the porosity qualitatively changed with the increase of AgNPs. It is obtained that the absorbance of the system is gradually reduced by the increase of AgNPs addition, except an increasing feature at 0.11 g addition of AgNPs. It was also revealed that the rise of AgNPs resulted in increasing the antibacterial activity as expected previously. [ABSTRACT FROM AUTHOR]

Vitrification has been widely used to preserve ovarian tissue. However, an efficient method with minimal damaging effect towards the tissue has not been established, yet. Accordingly, the combination method among intra- and extracellular cryoprotectant was conducted in this study. The aim of the research is to evaluate combination of ethylene glycol (EG) as intracellular cryoprotectant with egg yolk as extracellular cryoprotectant in reducing coldshock effect on ovarian tissue vitrification after 48 hours. Twenty one samples of twelve week-old female Sprague-Dawley rats are used in this study. Ovarian samples (n = 21) were washed in saline to clear excessive blood and were weighed. Samples for control groups (n = 3) were immediately fixated. Control treatment groups (n = 9) plunged into cryotube filled with 3.75 %, 7.5 % and 15 % of EG solution, respectively, while treatment groups (n = 9) were 3.75 %, 7.5 % and 15 % of egg yolk + EG solution, respectively. All samples were then frozen in liquid nitrogen (- 196 °C). After 48 hours, the samples were thawed and weighed. The result shown that based on Anova test there were no significant different (p < 0.05) in weight of ovarian tissue before and after vitrification. In conclusion, vitrification using a combination of ethylene glycol (EG) and egg yolk may have significant impact in preventing coldshock in the ovary. [ABSTRACT FROM AUTHOR]

Working fluids in heat exchanger commonly used water or ethylene glycol with their advantages and disadvantages. There was a development to disperse nanoparticles into base fluids, or known as nanofluids, to resolve the disadvantages of the working fluid. Nanoparticles gave fluids unique characteristics including an increase in heat transfer. Therefore, nanofluids had better heat transfer characteristics compared to conventional working fluids. This article discussed the effect of adding nanoparticles in TiO2-ethylene glycol nanofluid towards the heat transfer characteristics (Nusselt, Reynolds, ΔT LMTD, convective coefficient, overall heat transfer coefficient, and heat transfer) using heat exchanger device. The variation of nanoparticle concentrations in this research were 0%, 0.025%, 0.05%, and 0.075%. This research used laboratory-scaled heat exchanger type shell and tube as the heat transfer device, with the volumetric flow rate variations of 0.2, 0.4, and 0.6 l/m for each nanofluid sample. The test results showed that there was an increase along with the increasing nanofluid volumetric flow rate and the new nanoparticle concentrations. [ABSTRACT FROM AUTHOR]

This study investigates the effect of DI water and nanofluid on pressure drop and velocity characteristics of planar diverging and converging microchannels at different mass flow rates. Such channels can be used in microfluidic applications including microelectronic chip heat sinks. The length of the channel is kept 20 mm witha hydraulic diameter of 232 μm. Nanofluidconsists of Al2O3nanoparticles suspended in a 60:40 mixture of ethylene glycol and water. A CFD code is used to solve numerically the continuity and momentum equations to obtain the pressure drop and velocity distribution. Results show that pressure drop in case of nanofluid is about 7-8 times higher than DI water. In addition, the exit velocity of DI water is about 18-20% higher than the nanofluid under the same mass flow rate. [ABSTRACT FROM AUTHOR]