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하상백
- Proceedings of the Korean Society of Machine Tool Engineers Conference
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- 1999.10a
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- pp.519-524
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- 1999
To manufacture alumina products, sintering and grinding process are needed. In Al2O3 grinding, macro/micro surface fracture and cracks are easily occurred on the ground surface because of its high brittleness. In view point of fatigue fracture, surface profile produced by grinding is considered as notches. Therefore, it was reasonable that magnitudes and shapes of surface profiles effects on fatigue strength and life. Particularly, surface finish of Al2O3 which have high hardness and brittleness have an effect on fatigue strength. In this paper, some experiments are carried out to examine influence of grinding conditions to magnitude and shape of surface profile as well as the relationships of Ra, Rmax, Rmax/Ra, and Ku. Through the experimental results, It is found that Ra and Rmax was affected by grinding conditions, but Rmax/Ra and Ku was not. There are linear relations between Ra and Rmax, and between Rmax/Ra and Ku.
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Kim, Soochul;Lee, Kwanghee
- Conservation Science in Museum
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- v.9
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- pp.95-104
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- 2008
Wooden objects excavated from Gwangju Shinchang-dong, we analyzed total 40 pieces consisting of 37 pieces for analysis of species of trees, 3 pieces for analysis of lacquer. and especially it was found that in case of lacquerware and living goods like dish, diffuse-porous woods were used. As a result of this, total 7 species of trees used for wooden objects identified are Quercus spp., Cearsus spp., Prunophora spp., Acer spp., Salix spp., Populus spp. were identified. As a result of analyzing lacquered film, though there is a difference of times of lacquering between holed lacquerware and cylider type lacquerware body part 5, it was confirmed that after undercoating, black pigments and lacquer were painted on upper layer in mixture, and foundation platter for with 5 parts lacquer ware was undercoated with mixture of powdered soil, black pigments and lacquer, and then its upper layer was coated with lacquer mixed with black pigments.
https://doi.org/10.22790/conservation.2008.9.0095 인용 PDF

Lee, Seon Joo;Okada, Fumio
- Journal of Conservation Science
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- v.32 no.2
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- pp.109-121
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- 2016
Mother-of-pearl turtle shell lacquerware refers to a decoration made of a mother-of-pearl, a turtle shell and metal wires. This lacquerware features bright color tone as it is produced by sprinkling metal powder over its entire surface. This study aimed to find out its material properties and characteristics by using an optical microscopy and conducting a SEM-EDS analysis on the cross section of lacquer coating. As a result, it was found that charcoal powder and soil powder were mixed for undercoating. Then a mixture of cinnabar lacquer and monoclinic arsenic sulfide mineral ($As_2S_3$) was coated on the undercoating and brass powder was sprinkled on top of it. Especially, a little amount of pigment was found on the lacquer layer, which is distinguished from the colors used for conventional lacquer patterns. In addition, it was also found that the cinnabar lacquer and monoclinic arsenic sulfide mineral were mixed together.
https://doi.org/10.12654/JCS.2016.32.2.02 인용 PDF KSCI

Choi, Jaewan;Kim, Soo-Chul
- Journal of the Korean Wood Science and Technology
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- v.46 no.1
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- pp.1-9
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- 2018
Nowadays, synthetic resin varnish such as cashew nut shell liquid (CNSL) is being used as well as traditional lacquer. The code of ethics states that material must be identical to the original when preserving cultural heritage. Therefore, lacquer should be used. However, problem is that even experts have difficulties differentiating lacquer and CNSL as they have similar components. Therefore, this study was carried out to identify the difference between lacquer and CNSL using IR and Py-GC/MS. As a result of IR, in lacquer, $720cm^{-1}$ peak was detected and in CNSL, $750cm^{-1}$, $720cm^{-1}$ and $700cm^{-1}$ peaks were detected. The results of Py-GC/MS detect benzene compounds and alkyl chains for both varnishes. However, hexanoic acid was detected from CNSL but not lacquer. Using these analytical methods, the differences between lacquer and CNSL can be identified on the scene. This is expected to be applied to the authentic conservation and restoration of lacquerware.
https://doi.org/10.5658/WOOD.2018.46.1.1 인용 PDF KSCI

An, Jung Tae;Gene B. Carpenter
- Journal of the Korean Chemical Society
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- v.34 no.2
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- pp.130-135
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- 1990
The title compound (C13H17NO2S) is monoclinic, space group P21/a, with a = 13.756 (3), b = 9.310(4), c = 21.305(3) $\AA$, $\beta$ = 95.0。, Z = 8, V = 2718.11 $\AA$3, Dc = 1.23$g·{\cdot}cm-3$, (Mo k$\alpha$) = 0.71069$\AA$,$\mu$ = 2.18 cm-1, F(000) = 1071.86, T = 298, R = 0.085 for 2935 unique observed reflections with I >2.0$\sigma$(I). The structure was solved by direct methods. The C-H bond lengths and the methyl groups are fixed and refined as their ideal geometry by allowing to ride on the parent atoms. Both molecules A and B have almost same structures except for two terminal ethyl groups. The ethylene-like skeleton including the nitro group in one molecule is nearly perpendicular to the plane of the methylbenzene group and two ethyl groups form a cis-type structure which has the dfferent orientations between two molecules; in the molecule A, two terminal methyl groups being the opposite directional arrangement against the plane of its skeleton, while in the B, with the same directional structure from its plane. The molecules in the crystal are packed together by non-bonded van der Waals forces.
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