• Fashion & Textile Research Journal
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• 제12권2호
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• pp.219-223
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• 2010

In this study, the comfort properties of cotton and Hanjee fabrics dyed with Inonotus obliquus and treated with illite were evaluated and compared. Results were as follows; 1) W/T values and WC/W values of cotton and Hanjee fabrics were decreased when they were dyed with Inonotus obliquus and treated with illite. 2) Although air permeability of cotton fabrics was higher than that of Hanjee fabrics, air permeability of cotton and Hanjee fabrics dyed with Inonotus obliquus and treated with illite was decreased. 3) Thermal conductivity of cotton and Hanjee fabrics dyed with Inonotus obliquus was increased whereas thermal retain property was decreased. 4) Water absorption of Hanjee fabrics was higher than that of cotton fabrics. Water absorption of cotton and Hanjee fabrics dyed with Inonotus obliquus and treated with illite was increased. 5) Deodorization rate of Hanjee fabrics was greater than that of cotton fabrics.

• Journal of Welding and Joining
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• 제17권4호
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• pp.53-59
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• 1999

Amorphous alloys have also been called glassy alloys or non-crystalline alloys. They are made by the rapid solidification. The solidification occurs so rapid that the atoms are frozen in their liquid configuration. There are unique magnetic, mechanical, electrical and corrosive behaviors which result form their amorphous structure. In the study. amorphous coatings were manufactured with Ni-Cr-B-Si powders by flame spray. Measurement of hardness, were resistance, corrosion resistance and observation of microstructures and XRD, DSC were performed to investigate characteristics of amorphous coatings. The experimental results obtained as follow: 1) Amorphous powders could not be manufactured with the spraying in the spraying in the liquid nitrogen. But, amorphous coatings could be manufactured with the rotation cooling method by liquid nitrogen. In the fabrication of amorphous coatings, major factor was the rapid cooling by rotation of the substrate. 2) Hardness of coatings was obtained Hv 960 by formation of amorphous phase. But, wear resistance decreased. That was due to porosity in the coatings by the rapid cooling. 3) In the case of corrosion resistance, amorphous coatings were superior to air-cooled coatings. That was due to formation of amorphous phase. 4) After amorphous coatings were heat-treated at 520℃ for 1hr. hardness increased 80% and wear resistance increased 30% comparing with air cooled coatings. These were due to crystallization of amorphous phase and decrease of porosity by heat-treatment.

• Bulletin of the Korean Chemical Society
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• 제29권6호
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• pp.1121-1124
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• 2008

A carbon composite was synthesized by mechanical mixing of ball-milled graphite and PVC powders, followed by pyrolysis reaction of PVC. Natural graphite ball milled under atmosphere of argon or air leads to a disordered structure. It appears that the electrochemical lithium intercalation reaction is dependent on the atmosphere in which the graphite is ball milled. The carbon composite obtained using air-milled graphite shows a high reversible capacity and high initial coulombic efficiency compared to argon-milled graphite. This is attributed to the enhanced thermal stability of a disordered structure in the air milled sample. For the one with air-milled graphite, the disordered structure is maintained during heat treatment, while argon-milled graphite is partially crystallized.

• Journal of the Korean institute of surface engineering
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• 제45권2호
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• pp.70-74
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• 2012

In thermal barrier coating (TBC) systems, the life of the coating depends on thermally grown oxide (TGO) layer because most of the failure of TBCs occurs when TGO growth increases. In order to inhibit TGO growth, process was additionally carried out before the heat treatment of the TBC coating layer at $1200^{\circ}C$ in air. In the additional process, heat treatment in vacuum furnace of < $10^{-5}$ torr was conducted for 7 h and 14 h before the heat treatment. The area and length of TGO, as well as the crack length in the TBC were characterized using a scanning electron microscope (SEM). The TGO thickness and crack of specimens pre-heat treated in vacuum furnace were reduced by 45% compare to those heat treated in furnace. Consequently, pre-heat treatment in a vacuum furnace process lead to effective inhibition of growth of the TGO.

• The Research Journal of the Costume Culture
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• 제30권1호
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• pp.88-101
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• 2022

Molybdenum is used in electrical contacts, industrial motors, and transportation materials due to its remarkable ability to resist heat and corrosion. It is also used to flame coat other metals. This study investigated, the thermal characteristics of the molybdenum sputtered material, such as electrical conductivity, and stealth effects on infrared thermal imaging cameras. To this end, molybdenum sputtered samples were prepared by varying the density of the base sample and the type of base materials used. Thereafter, the produced samples were evaluated for their surface state, electrical conductivity, electromagnetic field characteristics, thermal characteristics, stealth effect on infrared thermal imaging cameras, and moisture characteristics. As a result of infrared thermal imaging, the molybdenum layer was directed towards the outside air, and when the sample was a film, it demonstrated a greater stealth effect than the fabric. When the molybdenum layer was directed to the outside air, all of the molybdenum sputtering-treated samples exhibited a lower surface temperature than the "untreated sample." In addition, as a result of confirming electrical properties following the molybdenum sputtering treatment, it was determined that the film exhibited better electrical conductivity than the fabric. All samples that were subjected to molybdenum sputtering exhibited significantly reduced electromagnetic and IR transmission. As a result, the stealth effect on infrared thermal imaging cameras is considered to be a better way of interpreting heat transfer than infrared transmission. These results are expected to have future applications in high-performance smartwear, military uniforms, and medical wear.

• The Journal of Advanced Prosthodontics
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• 제9권5호
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• pp.364-370
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• 2017

PURPOSE. To explore the influence of different surface conditionings on surface changes and the influence of surface treatments and aging on the bond strengths of composites to non-aged and aged resin nanoceramics. MATERIALS AND METHODS. Rectangular-shaped non-aged and aged (5000 thermocycles) resin nanoceramic specimens (Lava Ultimate) (n=63, each) were divided into 3 groups according to surface treatments (untreated, air abrasion, or silica coating) (n=21). The surface roughness was measured and scanning electron microscopy was used to examine one specimen from each group. Afterwards, the specimens were repaired with a composite resin (Filtek Z550) and half were sent for aging (5000 thermocycles, n=10, each). Shear bond strengths and failure types were evaluated. Roughness and bond strength were investigated by two- and three-way analysis of variance, respectively. The correlation between the roughness and bond strength was investigated by Pearson's correlation test. RESULTS. Surface-treated samples had higher roughness compared with the untreated specimens (P=.000). For the non-aged resin nanoceramic groups, aging was a significant factor for bond strength; for the aged resin nanoceramic groups, surface treatment and aging were significant factors. The failures were mostly adhesive after thermal cycling, except in the non-aged untreated group and the aged air-abraded group, which had mostly mixed failures. Roughness and bond strength were positively correlated (P=.003). CONCLUSION. Surface treatment is not required for the repair of non-aged resin nanoceramic; for the repair of aged resin nanoceramic restorations, air abrasion is recommended.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• 제11권1호
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• pp.47-52
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• 2005

The wasted plastic PC/ABS retainer, polyurethane foam (PUF) and vinyl (PVC) skin. In order to investigate the recycling process, the multi-layered instrument panel Each of materials separated was shredded and crushed to create many small particles respectively. The separation of the foam and skin and retainer of zigzagged air blower. Pilot tests performed at the equipment yielded 98.8% by weight of the available PVC and 99.3% by weight of the available PC/ABS respectively. Secondly, the thermal stabilizer and the compatabilizer have been used to improve the physical propertied of recycled materials.. The properties of recycled PVC materials resulted in about 50% compared to that of virgin materials after treatment by Pb-St thermal stabilizer. In addition, the properties of recycled PC/ABS materials was also obtained about 80% compared to that of virgn materials after treatment by PMMA compatabilizer.

• Textile Coloration and Finishing
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• 제10권3호
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• pp.10-19
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• 1998

This paper investigates the change of mechanical properties and thermal shrinkage in commercial multi-filament PET(polyethylene terephthalate) , namely, regular yarn, POY, DTY and composite yarn. To determine changing the effects of processing steps, these were examined at three steps process simulation conditions. The first step is sizing simulation$(S-1\;step\;:\;130^\circ{C}\times2\;min$., hot air treatment under 0.1 gf/d load), the second step is scouring simulation$(S-2\;step\;:\;100^\circ{C}\times20\;min$., boiling water treatment under free tension)and final step is setting simulation$(S-3\;step\;:\;180^\circ{C}\times2\;min$., hot air treatment under free tension). Regular yarn in multi-step treatment showed higher shrinkage at S-3 step and DTY showed higher in at S-1 step. While POY was relaxed at S-1 step, composite yarn showed different shrinkage properties depending on composite yarn type. Mechanical properties showed good relationship with shrinkage : high shrinkage makes initial modulus decrease and bleating strain increase. It also makes decreasing yield strain and yield stress decrease.

• Journal of Microbiology and Biotechnology
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• 제32권6호
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• pp.768-775
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• 2022

In this study we aimed to derive the response surface models for Escherichia coli reduction in wheat flour using atmospheric cold plasma (ACP) with three types of gas. The jet-type atmospheric cold plasma wand system was used with a 30 W power supply, and three gases (argon, air, and nitrogen) were applied as the treatment gas. The operating parameters for process optimization considered were wheat flour mass (g), treatment time (min), and gas flow rate (L/min). The wheat flour samples were artificially contaminated with E. coli at a concentration of 9.25 ± 0.74 log CFU/g. ACP treatments with argon, air, and nitrogen resulted in 2.66, 4.21, and 5.55 log CFU/g reduction of E. coli, respectively, in wheat flour under optimized conditions. The optimized conditions to reduce E. coli were 0.5 g of the flour mass, 15 min of treatment time, and 0.20 L/min of nitrogen gas flow rate, and the predicted highest reduction level from modeling was 5.63 log CFU/g.

• International Journal of Air-Conditioning and Refrigeration
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• 제13권2호
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• pp.99-106
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• 2005

Falling film heat transfer has been widely used in many applications in which heat and mass transfer occur simultaneously, such as evaporative coolers, cooling towers, absorption chillers, etc. In such cases, it is desirable that the falling film spreads widely on the surface to form a thin liquid film to enlarge contact surface and to reduce the thermal resistance across the film and/or the flow resistance to the vapor stream over the film. In this respect, hydrophilic treatment of the surface has been tried to improve the surface wettability by decreasing the contact angle between the liquid and the surface. However, the hydrophilic treatment was found not very effective to increase the surface wettedness of inclined surfaces, since the liquid flow forms rivulet patterns instead of a thin film as it flows down the inclined surface and accelerates gradually by the gravity. In this work, a novel method is suggested to improve the surface wettedness enormously. In this work, the surface is treated to have a thin hydrophilic porous layer on the surface. With this treatment, the liquid can spread widely on the surface by the capillary force resulting from the porous structure. In addition to this, the liquid can be held within the porous structure to improve surface wettedness regardless of the surface inclination. The experiment on the evaporative cooling of inclined surfaces has been conducted to verify the effectiveness of the surface treatment. It is measured that the latent heat transfer increases almost by $80\%$ at the hydrophilic porous layer coated surface as compared with the untreated surface.