• Journal of the Korean Ceramic Society
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• v.33 no.9
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• pp.1057-1063
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• 1996

Y2O3-CeO2-ZrO2 powders were prepared from water-soluble salts using a coprecipitation method. The forming process of oxide and the characteristics of the calcined powders treated in different drying conditions were investigated. The oxidation was occurred at the temperature of around 40$0^{\circ}C$ and the main crystallization of ZrO2 around $600^{\circ}C$. On calcination at $600^{\circ}C$ heating lamp-dried powders consisted of agglomerates of globular morphology with average agglomerate size of 2.27${\mu}{\textrm}{m}$ and specific surface area of 68.3m2/g and spray dried powders contained dense spheric particles with average agglomerate size of 1.35${\mu}{\textrm}{m}$ and specific surface area of 11.0m2/g which exhibited low agglomeration tendency. Removal of the water by a freeze-drying technique produced calcined powders containing flake-like secondary particle structures with wide agglomerate size distri-bution of 0.1-60${\mu}{\textrm}{m}$ and specific surface area of 24.5${\mu}{\textrm}{m}$. The 20 MPa-pressed density (36.8-41.4% T,D) of calcined powders did not nealy depend on drying methods whilst compaction ratio of calcined powders derived from freeze-drying was the highest ( 6.24) among three drying methods. On continuous heating up to 150$0^{\circ}C$ the sinterability of calcined powders derived from heating lamp-drying was superior to those derived from spray-and freeze-drying. The final sintered density of calcined powders was the highest (96% T,D at 150$0^{\circ}C$) in case of heating lamp-drying.

• Journal of Korea Society of Industrial Information Systems
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• v.23 no.3
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• pp.25-34
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• 2018

This paper presents a heating source of carbon nanofibers for the efficiency and the drying performance of laundry dryer, and focuses on the applicability-evaluation of its source. To design the proposed heating module, experiments were conducted in terms of surface temperature and surface temperature distribution characteristics of carbon nanofiber lamps. The surface temperature of the lamps increased linearly with increment of a current to flow a lamp and revealing the increasing pattern as the length of the ramps is shorter. The proposed heating source was evaluated based on drying efficiency, moisture evaporation rate at laundry, and internal temperature of a drum during drying process. The drying efficiency satisfied a 45% which is specified in KS C 9319. The moisture evaporation rate and the internal temperature of the drum were respectively 98.88% and $61.1^{\circ}C$, which are similar to that of S's company dryer. From the evaluation and actual drying test results, the proposed carbon nanofiber lamp heating module is considered to be applicable as a heat source for laundry dryer in terms of drying efficiency and drying performance. it is possible to obtain a heat source at a high temperature, an excellent calorific value, an improvement in drying performance, and an effect of sterilizing laundry due to the emission of far-infrared rays. In addition to the applicability, the difference of the drying efficiency between the dryers was analyzed in detail based on the power consumption of the heat sources.

• Journal of the Korean Wood Science and Technology
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• v.36 no.6
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• pp.105-112
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• 2008

Grading of the urushi lacquer is quite difficult because of large variations depending on origin, growing conditions, time acquisition, storage conditions. It is urgently required to establish a grading system of urushi lacquer by combining traditional method with scientific methods. Traditional grading of urushi lacquer was done by visual inspection of 10 experts who are working on urushi lacquer industry. Common aspects of the experts were color, odor, viscosity, spread properties on Hanji, color and drying properties on glass based the traditional grading system. In addition, rubbing on Hannj and heating with alcohol lamp was also used to grade urushi lacquer. The grading results of 10 experts showed that chinese urushi lacquer (E) of 7.03, japanese urushi lacquer (C) of 6.84, domestic urushi lacquer of (A) of 6.41 and another chinese urushi lacquer (D) of 5.27, and domestic urushi lacquer (B) of 2.50 in descending order. The degree of spread on Hanji was not consistent among 10 experts. These results indicated that the traditional grading system was pretty much personal and required of developing more objective method based on scientific background.