• Journal of the Korean Ceramic Society
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• v.45 no.5
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• pp.303-308
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• 2008

Mullite precursors were synthesized with aluminosilicate gels from mixture of aluminum nitrate and sodium orthosilicate by the geopolymer technique at ambient temperature. Then, the gel was heat-treated in air up to $1200^{\circ}C$ at intervals of $100^{\circ}C$. Raw and heat-treated gels were characterized by TG-DTA, XRD, FTIR, $^{29}Si$ MAS-NMR, TEM. The result to examine the crystallization of behavior though DTA, the synthesized precursors were crystallized in the temperature range from $950^{\circ}C$ to $1050^{\circ}C$. The XRD results showed that the gel compositions were begun to crystallize at various temperature. Also, it was found that the precursors of M-4 begun to crystallize at about $950^{\circ}C$. The M-4 XRD peaks were characterized better than $M-1{\sim}M-3$ at $1000^{\circ}C$. The formation temperature of mullite in this study is much lower than that of previous sol-gel methods, which crystallized at up of $1200^{\circ}C$. TEM investigations revealed that the sample with 10 nm particle size was obtained via heat-treated at $1000^{\circ}C$ for M-4.

• Journal of the Korean Home Economics Association
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• v.37 no.12 s.142
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• pp.193-203
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• 1999

This study was executed to show influence of material and property of sportswear to physiological responses of body and comfort sensation and to supply basic research data about comfortable sportswear Trainning wear was manufactured with cotton(C) and hygroscopically treated polyester material (FP), and its properties of material were measured. Then rectal temperature, skin temperature, heart rate, weight loss, clothing microclimate and subjective sensation was estimated with study of wearing with these sportswear and examined the influence that it got to physiological responses of body and sensation. Health adult men were selected for subjects and executed at climatic chamber of temperature, $20\pm2^{\circ}C and humidity, $60\pm5%$ R.H. Conclusively sportswear of hygroscopically treated polyester is a favorable functional material. So far factor that affect to physiological comfort sensation has been explained mostly by moisture regain but in our experiment, it turned out that air permeability, water absorption velocity and dynamic oater absorption etc. were affecting factors. So according to this result, air permeability and moisture permeability should be considered with transmittance of temperature moisture for development of comfort material.

• Korean Journal of Plant Resources
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• v.10 no.4
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• pp.392-396
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• 1997

The present study was performed to obtain a basic data of cultivation for Condonopsis lanceolata. Various temperatures, light, and DIF were treated during the whole plant growth. The growth of aerial part was most remarkable between $20^{\circ}C$ and $25^{\circ}C$, but inhibited by means of shading treatment. The fresh weight of subterranean part was heaviest(16.6g) at $15^{\circ}C$. Also, plant height increased when a constant temperature and +DIF were treated. Leaf width and length was not related to temperature and DIF treatment. The fresh weight of subterranean part increased in +DIF-treated sample at $25^{\circ}C$.

• Journal of the Korean Ceramic Society
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• v.34 no.9
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• pp.935-940
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• 1997

This study investigated the crystallization behavior in PbO-ZnO-B2O3-TiO2 system sealing glass, inorganic polymer heat-treated by conventional heat and microwave energy. After determining heat-treated temperature for crystallization and characteristic points by DTA analysis, samples were heat-treated in a classical electric furnace and a home-style microwave oven (LG Electronic Co., 2.45 GHz, 700 W). A microwave heat-treated sample had the growth of PbTiO3 crystal at 45$0^{\circ}C$, 2$0^{\circ}C$ lower than that of a conventionally heat-treated sample. Also, it had crystallinity about 20% higher than the conventionally heat-treated sample. At 49$0^{\circ}C$, the size of PbTiO3 crystal in the conventionally heat-treated sample was larger than that in the microwave heat-treated sample due to longer heat-treated time.

• Journal of the Korean Society of Safety
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• v.13 no.3
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• pp.88-95
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• 1998

In this paper, we investigated the change of wettability, surface potential decay and dielectric properties caused by ultraviolet-treated, thermal-treated and discharge-treated FRP(fiber reinforced plastics) respectively for finding out the influence of dry treatments effected to electrical characteristics on the surface of polymer composites. For the change of wettability, the contact angle of thermal-treated specimen with the high temperature of $200^{\circ}C$ increased. But that of UV-treated and discharge- treated specimen decreased. The characteristic of surface potential decay shows the tendency of the remarkable decrease on UV-treated and discharge-treated specimens, but no difference on thermal-treated specimen compared with untreated one. Also, for the dielectric properties, it shows the increase at large on the treated specimens and especially, the remarkable increase on thermal-treated one.

• Korean Journal of Metals and Materials
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• v.47 no.10
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• pp.629-634
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• 2009

The effects of processing parameters on the surface properties of the hardened layers processed by the low temperature plasma nitrocarburizing and the low temperature two-step plama treatment (carburizing+nitriding) were investigated. The nitrogen-enriched expanded austenite structure (${\gamma}_N$) or S phase was formed on all of the treated surface. The surface hardness reached up to 1200 $HV_{0.025}$, which is about 5 times higher than that of untreated sample (250 $HV_{0.1}$). The thickness of hardened layer of the low temperature plasma nitrocarburized layer treated at $400^{\circ}C$ for 40 hour was only $15{\mu}m$, while the layer thicknesss in the two-step plama treatment for the 30 hour treatment increased up to about $30{\mu}m$. The surface thickness and hardness increased with increasing treatment temperature and time. In addition, the corrosion resistance was enhanced than untreated samples due to a high concentration of N on the surface. However, higher treatment temperature and longer treatment time resulted in the formation of $Cr_2N$ precipitates, which causes the degradation of corrosion resistance.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.58-65
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• 2008

To see the possibility of irradiation as an alternative to ultra high temperature (UHT) sterilization, the quality characteristics of milk were analyzed. Milk treated by UHT ($135^{\circ}C$ for 4 sec) and irradiation at higher than 3 kGy showed no viable counts after 7 days of storage at $4^{\circ}C$. The contents of certain amino acids of milk, such as Arg, Asp, Glu, Ile, Leu, Lys, Pro, Ser, Thr, and Tyr, were lower in irradiated groups at 10 kGy than in UHT-treated one, but no difference was observed between irradiated milks at less than 5 kGy and UHT. The capillary electrophoresis (CE) patterns of the milk irradiated at 10 kGy showed a similar trend to the raw milk, low temperature long time (LTLT, $63^{\circ}C$ for 30 min), and high temperature short time (HTST, $72^{\circ}C$ for 15 sec) treated. However, the CE pattern of UHT-treated milk was different. Rennet coagulation test agreed with the CE results, showing that all milk samples were coagulated by rennet addition except for UHT-treated milk after 1 hr. These results suggest that irradiation of milk reduce the content of individual amino acids but it may not induce severe conformational change at a protein level when compared with UHT treatment.

• Textile Coloration and Finishing
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• v.5 no.4
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• pp.49-59
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• 1993

In order to study the bleaching of cotton fabrics, ozone which has been produced by an ozone generator, has been contacted with cotton fabrics in water at various conditions. The equipments used for the ozone treatment of cotton fabrics were the ozone generator and a liquor/ozone contactor. For the examination of the ozone bleaching effect on cotton fabrics the whiteness, tensile strength, wettability and clark softness of the ozone treated cotton fabrics were measured. The conclusion obtained were, ozone concentration was increased, as the voltage was increased and flow rate was decreased and oxygen amount was increased. Bleaching effect of treated fabrics increased with increasing attributed more the net concentration of ozone rather than the total ozone amount of produced. The whiteness of treated fabrics was found to be best when treating temperature was 15~20<$^{\circ}C$, in acidic condition. The tensile strength of treated fabrics decreased as the treating time increased, and as the temperature raised, and the acidity increased. The wicking distance of treated fabrics increased slightly with increasing the treating time and the temperature. Clark softness of treated fabrics was not changed until passing 30min. of the treating time, then it decreasing linealy with increasing the treating time.

• Journal of the Korean Wood Science and Technology
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• v.32 no.2
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• pp.50-57
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• 2004

This study attempted to evaluate the water repellency and drying effectiveness of linseed oil treated-solid wood at high temperature by immersion. The moisture content of green wood (Pinus densiflora) sample (above 90%) was reduced about 10% after 6 hours treatment at 150℃. When the treated samples were cut into cross section along the length, it was observed that the linseed oil penetrated into up to 20% of the sample cross section area in all locations. However, a strength loss of the specimen was not detected. The pre-drilling before linseed oil treatment was effective in reducing the defects such as checks and splits, and improved the linseed oil penetration into all samples from the surfaces. The result of water absorption test of treated-wood showed that the water repellent efficacy of treated-wood was greater than that of the control. The anti-fungal activity of treated samples using five sap stains and thee decay fungi was not detected in broad-spectrum toxic mechanism. However, decay test using white rot fungi (Tyromyces palustris) and brown rot fungi (Trametes versicolor) showed that the treated sample has a decay resistance to these two fungi.

• Journal of the Korean Ceramic Society
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• v.31 no.1
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• pp.97-103
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• 1994

The influence of ground petroleum coke, preheat-treated at temperatures ranged of 150~35$0^{\circ}C$, was studied. It has been found that the coke powder preheat-treated at the temperature of 175$^{\circ}C$ has been spherical-shaped in grinding and have showed the highest strength and density in sintering. The coke powder was also the best for the binding force and the (H/C) values showed 0.45 at the above temperature.