• Tribology and Lubricants
• /
• v.12 no.3
• /
• pp.107-114
• /
• 1996

MoS$_{2}$ bonded film was applied to reduction gears, and its lubricating properties were experimentally evaluated in terms of the power transmission efficiency and the frictional noise with a dynamo-typed gear test rig. Tests were performed in both oil lubrication and dry condition where the rotating velocity and loading torque were varied. In dry condition, MoS$_{2}$ bonded films effected the power transmission efficiency to increase about 5%, and the frictional noise level to decrease about 6 dB under the test operating conditions. It well proved that MoS$_{2}$ bonded films were a very effective solid lubricant for reduction gears. In oil lubricating conditions, the frictional properties of the coated gears were mainly governed by the lubricating oil, and lubricating effects of MoS2 bonded films were not evident. The result suggested that lubricating effect of MoS$_{2}$ bonded films would be limited to prevent a damage of reduction gears in the initial run when they were used in oil lubrication conditions.

• Food Science of Animal Resources
• /
• v.36 no.3
• /
• pp.377-388
• /
• 2016

Objective of the present study is to investigate the effect of coated edible films with chitosan solutions enriched with essential oil (EO) on the chemical, microbial and sensory properties of Kashar cheese during ripening time. Generally, no differences were found in total aerobic mesophilic bacteria, streptococci and lactoccocci counts among cheeses but these microorganism counts increased during 60 and 90 d storage especially in C1 (uncoated sample) as compared with coated samples. Antimicrobial effectiveness of the films against moulds was measured on 30, 60, and 90 d of storage. In addition of fish EO into chitosan edible films samples were showed to affect significantly decreased the moulds (p<0.05) as 1.15 Log CFU/g in C4 (with fish oil (1% w/v) fortified chitosan film) on the 90^th d, while in C1 as 3.89 Log CFU/g on the 90^th d of ripening. Compared to other cheese samples, C2 (coated with chitosan film) and C4 coated cheese samples revealed higher levels of water-soluble nitrogen and ripening index at the end of storage. C2 coated cheese samples were preferred more by the panellists while C4 coated cheese samples received the lowest scores.

• Polymer(Korea)
• /
• v.27 no.1
• /
• pp.3-8
• /
• 2003

Polysiloxanes with methacrylate groups at both terminals were synthesized by a hydrosilylation reaction between allyl methacrylate and hydride-terminated polysiloxanes. The polysiloxane methacrylates with high molecular weights could be prepared through the reaction of polysiloxane methacrylates and octamethylcyclotetrasiloxane with an acid catalyst. The structures of the prepared polysiloxane methacrylates were verified by $^1$H- and $^{29}Si-NMR.$ The polysiloxane methacrylates were freely miscible with silicone oils. Polysiloxane films with microphase-separated liquid silicone oil were prepared by photo-crosslinking the mixture of polysiloxane methacrylates and silicone oil. Scanning electron microscopy (SEM) of the films showed that the size of silicone oil droplets became smaller with a lower loading of silicone oil, lower molecular weight of polysiloxane methacrylate, and lower molecular weight of silicone oil.

• 한국신재생에너지학회:학술대회논문집
• /
• 2010.11a
• /
• pp.60.1-60.1
• /
• 2010

Chemically functionalized plant oils such as acrylated epoxidized soybean oil (AESO) and maleinized acrylated epoxidized soybean oil (MAESO) were used as new bio-based binders for $TiO_2$ electrodes of dye-sensitized solar cells (DSSC). More porous networks and larger porosities were fabricated on the $TiO_2$ films using plant oil binders due to the larger number of functionalities, in comparison with the film using polyethylene glycol (PEG). The charge-transfer resistance in the $TiO_2$ films was considerably shrunk due to the reduced impurity states. The short circuit photocurrent (Isc) and the open circuit photovoltage (Voc) of the cell using plant oil binders increased and the conversion efficiency improved significantly.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.4 no.4
• /
• pp.58-71
• /
• 1996

A model which calculates the hydrocarbon emissions from spark ignition engines is presented The model contains the formation of HC emissions due to both crevices around piston ring top land and oil films on the cylinder wall. The model also considers in-cylinder oxidation and exhaust port oxidation of desorbed HC from crevices and oil films after combustion process. The HC emissions model utilizes the results of SI engine cycle simulation. The model predicts well the trends of HC emissions from the engines when varying engine parameters.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.23 no.2
• /
• pp.71-96
• /
• 1997

We have used a novel liquid surface forces apparatus to determine the variation of disjoining pressure with film thickness for dodecane-water-dodecane emulsion films. The LSFA allows measurement of film thicknesses in the range 5-100 nm and disjoining pressure from 0-1500 Pa. Disjoining pressure isotherms are given for films stabilised by the nonionic surfactnat n-dodecyl pentaoxyethylene glycol ether$(C_{12}E_5)$ and n-decyl-$\beta$-D-glucopyranoside($C_{10}- $\beta$-Glu)$ and the anionic surfactant sodium bis(2-ethylhexyl) sulphosuccinate(AOT) in the presense of added electrolyte. For $C_{12}E_5$ and AOT, the emulsion films are indefinitely stable even for the highest concentration of NaCl tested (136.7 Nm) whereas the $C_{10}-{eta}-Glu$ film shows coalescence at this salt concentration. For film thicknesses greater than approximately 20 nm with all three surfactants, the disjoining pressure isotherms are reasonably well described in terms of electrostatic and van der Waals, forces. For the nonionic surfactant emulsion films, the charge properties of the monolayers are qualitatively similar to those seen for foam films. For AOT emulsion films, the monolayer surface potentials estimated by fitting the isotherms are similar to the values of the zeta potential measured for AOT stabilised emulsion droplets. For thin emulsion films certain systems showed isotherms which suggested the presence of an additional repulsive force with a range of approximately 20 nm.

• Food Science of Animal Resources
• /
• v.43 no.6
• /
• pp.1128-1149
• /
• 2023

In order to extend the shelf life of refrigerating raw lamb by inhibiting the growth of microorganisms, preventing the oxidation of fat and protein, and absorbing the juice outflow of lamb during storage, an active packaging system based on plastic/gelatin bilayer film with essential oil was developed in this study. Three kinds of petroleum-derived plastic films, oriented polypropylene (OPP), polyethylene terephthalate, and polyethylene, were coated with gelatin to make bilayer films for lamb preservation. The results showed significant improvement in the mechanical properties, oxygen, moisture, and light barriers of the bilayer films compared to the gelatin film. The OPP/gelatin bilayer film was selected for further experiments because of its highest acceptance by panelists. If the amount of juice outflow was less than 350% of the mass of the gelatin layer, it was difficult for the gelatin film to separate from lamb. With the increase in essential oil concentration, the water absorption capacity decreased. The OPP/gelatin bilayer films with 20% mustard or 10% oregano essential oils inhibited the growth of bacteria in lamb and displayed better mechanical properties. Essential oil decreased the brightness and light transmittance of the bilayer films and made the film yellow. In conclusion, our results suggested that the active packaging system based on OPP/gelatin bilayer film was more suitable for raw lamb preservation than single-layer gelatin film or petroleum-derived plastic film, but need further study, including minimizing the amount of essential oil, enhancing the mechanical strength of the gelatin film after water absorption.

• Textile Coloration and Finishing
• /
• v.24 no.4
• /
• pp.313-320
• /
• 2012

For the preparation of hardened films which can be applied as a binder for flame-resistant materials such as silica, linseed oil was subjected to a low temperature plasma treatment with argon, or oxygen gas. The film was produced much faster than so-called drying of oil in air. The SEM analysis for silica particles embedded in the hardened film after plasma treatment showed that the silica particles were immobilized on substrate and were evenly dispersed. The FT-IR spectral analysis for the plasma-treated linseed oil films demonstrated that the radicals which were formed during the plasma treatments caused the linseed oil to be cross-linked, and the plasmas attacked carbon chains of the oil randomly without focusing on specific vulnerable bonds such carbon double and carbonyl bonds intensively unless exposure times of the plasmas were prolonged too much, while the cross-linking of the air-dried film was considered to occur at the well-known typical sites, i.e., carbon-carbon double bond and ${\alpha}$-methylene carbon. Burning times, as a measure of flame/fire resistance, of silica-filled cellulose substrates, increased with increasing contents of silica.

• Korean Chemical Engineering Research
• /
• v.61 no.4
• /
• pp.584-590
• /
• 2023

In this study, we focus on the recycling of cardboard waste and sugarcane bagasse (SCB) for the preparation of carboxymethyl cellulose (CMC) and its conversion into a biodegradable film. Sodium alginate (SA) was added to form a biodegradable composite film. SA was used to increase film permeability. Glycerol, which is a plasticizer, was used to increase the tensile strength (TS) and film expansion. To characterize the CMC, X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy were used. The addition of olive oil to the CMC-SA matrix highlighted its antimicrobial property against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). A slight decrease in tensile strength was observed with the addition of olive oil (OO), which improved the functional properties of the control films as well as lowered moisture content and water solubility. But considering all other factors, the composite films obtained from sugarcane bagasse and cardboard waste incorporated with olive oil are suitable for applications in the field of food packaging.

• Food Science of Animal Resources
• /
• v.36 no.3
• /
• pp.421-426
• /
• 2016

Polylactic acid (PLA) is a biodegradable and renewable polymer, which represents a valuable alternative to plastic packaging films, often associated with environmental problems. In this study, we tested the suitability of PLA as a biodegradable packaging film and assessed the antimicrobial activity of lemongrass oil (LO), incorporated into the PLA film in different concentrations. To obtain the optimal physical properties for PLA films, tensile strength, elongation at break, and water vapor permeability were measured under different preparation conditions. In addition, the antimicrobial activity of the LO contained in the PLA film against Listeria monocytogenes was investigated by disc diffusion and viable cell count. Among all concentrations tested, 2% LO was the most suitable in terms of antimicrobial activity and physical properties of the PLA film. Based on these results, we used the PLA film containing 2% LO to pack pork sausages; after 12 d of storage at 4℃, the population of inoculated L. monocytogenes in the sausage samples wrapped with the PLA film containing 2% LO was reduced by 1.47 Log CFU/g compared with the control samples. Our data indicate that PLA films containing 2% LO represent a valuable means for antimicrobial sausage packaging.