nan Masturi

Electrical and Magnetic Properties of Polymer Electrolyte (PVA:LiOH) Containing In Situ Dispersed Fe3O4 Nanoparticles

Nanocomposite magnetic polymer electrolytes based on poly(vinyl alcohol) (PVA) complexed with lithium hydroxide (LiOH) and containing magnetite (Fe3O4) nanoparticles were prepared using an in situ method, in which the nanoparticles were grown in the host polymer electrolyte. Ion carriers were formed during nanoparticle growth from the previously added LiOH precursor. If a high concentration of LiOH was added, the remaining unreacted LiOH was distributed in the form of an amorphous complex around the Fe3O4 nanoparticles, thus preventing agglomeration of the nanoparticles by the host polymer. By addition of Fe3O4 the composite polymer electrolytes improved the ionic conductivity, resulting in a maximum conductivity of 1.81×10−3 S·cm−1. The magnetic properties of the polymer electrolyte were investigated through magnetic susceptibility studies, and the material was predominantly ferromagnetic.

Resistors Network Model of Bcc Cell for Investigating Thermal Conductivity of Nanofluids

A model was developed to investigate thermal conductivity of nanofluids. It was based on resistors circuit network in bcc cell as alternative form of simple cubic cell has been successfully developed. The present model has involved the Brownian motion of nanoparticles in the fluid with an assumption that the nanoparticles are in low volume fraction so the diameter size of nanoparticle can be neglected in comparison to particles distance. Generally, this model was very fit to experimental results has been obtained from some authors. As an example, for alumina‐water nanofluid, that is alumina (Al2O3) dispersed in water, it was found that the enhancement of its thermal conductivity calculated using this model was in good agreement with experimental results that it tended to increase as nanoparticle fraction increases. As in alumina‐water, the agreement was also shown in titania (TiO2)‐water and cuprum oxide (CuO)‐water. This model also showed the dependence of thermal conductivity enhancement to diameter siz...

Titania Coated Ceramic Membrane from Clay and Muntilan Sand for Wastewater Filter Application

A ceramic membrane was fabricated from clay and Muntilan sand using sol-gel method with certain amount of titania coated on the membrane surface. Polyethylene glycol (PEG) was used as a pore-agent. The main steps of the process are hot-pressing and calcination. Varying the clay:sand:PEG ratio membranes permeability was obtained between 6.39 x 10-13 m2/Pa.s and 1.39 x 10-11 m2/Pa.s. The addition of sand volume fraction improves the permeability produced as result of the larger of the sand particle producing the higher pores. The filtration performance was tested using aqueous solutions of methylene blue (MB) as one of the main pollutants produced from textile industries. Under a pressure difference of 4 kPa, the concentrations of MB remaining in the solution varied from 1.73% to 10.29% depending on the permeability. Therefore, the membrane is very potential to be applied as wastewater filter for coping with the availibity of clean water.

NONLINEAR OSCILLATION MODEL FOR EXPLAINING THE DISTRIBUTION OF POSITION DEVIATION IN SELF-ORGANIZED NANOPARTICLES

A model for explaining deviations of positions in self-organized nanoparticles on a substrate from their corresponding positions in perfect organization is proposed. The model predictions were compared with SEM/TEM images and reported by some authors. We found a consistence between the model predictions with the data of Ag, Fe3O4 and SiO2 nanoparticles organization on various substrates.

Optimization of Coating Temperature of TiO2 Nanoparticles on the Polypropylene Copolymer Surface for Photodegradation of Methylene Blue

TiO2 nanoparticles have been coated on the polypropylene (PP) copolymers using a milling method with temperature controller modification. These experiments were carried out at different milling temperature: 100 °C, 110 °C, 120 °C and 130 °C for 90 minute milling time for each experiment. Photocatalytic degradation of methylene blue (MB) was investigated using TiO2 coated PP copolymer which floats on the MB solution and illuminated under sunlight for 36 hours. It was found that TiO2 coated PP polymer at temperature of 100 °C resulted in optimum decomposition of MB solution. The concentration of MB in a test solution after 18 hours of exposure to the sun was 15.42%. The reaction rate constants (k) and the half‐reaction (t1/2) in the MB photodegradation using the catalysts with a coating temperature of 100 °C, are 0.106 hours−1 and 6.53 hours, respectively. This coated material is very potential for repeated use to purify bulk water in high sunlight intensity region.

Effect of Silica Nanoparticles on Compressive Strength of Leaves-Waste Composite

The utilization of solid‐waste, especially leaves‐waste is one of interesting research of environmental field. One of them is making a composite using polyvinyl acetate (PVAc) polymer as binder (matrix) and silica nanoparticles as reinforcement (filler) to improve the strength of composite‐produced. Those raw materials preliminary were mixed by simple mixing with varied compositions and then hot‐pressed at 36 MPa and 100 °C for 20 minutes. From compressive strength test, it was found that composite with composition 7:8 of PVAc and leaves‐waste had maximum compressive strength, i.e. 57.60 MPa. It was also that the enhancement of strength due to PVAc fraction (w/w) increasing is a percolation behavior, even though its mathematical explanation has not been performed. Into composition of maximum strength above, silica with average size is 74 nm then was added to improve the strength and found that at silica weight fraction of 0.79 (%w/w), the composite had optimum compressive strength, i.e. 70.5 MPa, or incre...

Electrical and Magnetic Properties of Polymer Electrolyte PVA.LiOH Dispersed by Fe3O4 Nanoparticles

Nanocomposite magnetic polymer electrolyte based on poly (vinyl alcohol) (PVA) with lithium hydroxide (LiOH) dispersed by magnetite (Fe3O4) nanoparticle as inorganic filler were prepared by using an in‐situ method. Ions carriers were inserted during the growth of the nanoparticles that had been contributed by a precursor. The effect upon the addition of Fe3O4 nanoparticles on the ionic conductivity of the composite polymer electrolytes was investigated, and it was proven that the ionic conductivity had been enhanced. Maximum conductivity was obtained upon addition of Fe3O4 nanoparticles, i.e. 1.81×10−3S.cm−1. The magnetic properties of nanocomposite magnetic polymer electrolyte were observed by magnetic susceptibility studies. The magnetic susceptibility data revealed that polymer electrolyte PVA.LiOH dispersed by Fe3O4 nanoparticle was found predominantly ferrimagnetism.

High Strength Lightweight Nanocomposite from Domestic Solid Waste

The issue of waste problems needs innovative efforts to solve. One of them is solid waste utilization as nanocomposite using polyurethane (PU) polymer as matrix. Beside using solid waste as filler, nanosilica is also added to improve the material strength of composite‐produced. These materials were mixed by simple mixing with variative compositions, and then hot‐pressed at 30 MPa and 100° C for 30 minutes. From compressive strength test, it was found that composite with composition 2:8 of PU and solid waste has optimum compressive strength, i.e. 160 MPa. Into this optimum composition, nanosilica then is added to improve the compressive strength and found that at composition 1:40:160 of nanosilica, PU and solid waste, the composite has optimum compressive strength 200 MPa, or increases 25% of that without nanosilica. The composite‐produced is also lightweight material with the density is 0.69 g/cm.

A Novel Method for Synthesis of TiO2 Nanoparticles‐coated Plastic Fibers Using a Vibration Method and the Use of Coated Fibers as Photocatalitic Materials for Decomposing of Organic Pollutant in Water under Sunlight Illumination

Photocatalytic is a catalyst process that requires light energy in process of converting material in a chemical reaction. TiO2 is one of the most suitable materials in photocatalytic process. In this study, TiO2 nanoparticles‐coated plastic fibers made by using vibrating method. TiO2 nanoparticles‐coated plastic fibers products used for wastewater purification using photocatalytic process. Speed of water purification is influenced by TiO2 nanoparticles‐coated plastic fibers position on container. TiO2 nanoparticles‐coated plastic fibers with horizontal position on container has a faster photocatalytic process compared to TiO2 nanoparticles‐coated plastic fibers with vertical position on container.