• Bulletin of the Korean Chemical Society
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• v.4 no.3
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• pp.143-148
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• 1983

Two series of thermotropic compounds were prepared and their thermal and liquid crystal properties were examined by differential scanning calorimetry and on the hot-stage of a cross-polarizing microscope. The first series of the compounds has two terminal mesogenic units based on unsubstituted and substituted p-(phenoxycarbonyl) phenyl ethers bracketing a central decamethylene spacer, and the second has 4-(p-phenylphenoxycarbonyl) phenyl ether moiety as the two terminal mesogenic units and central polymethylene spacers of varying lengths. A thermodynamic analysis of the phase transitions was made and explained in relation to structures and thermotropic behavior of the compounds.

• Bulletin of the Korean Chemical Society
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• v.11 no.4
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• pp.333-339
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• 1990

A series of new dimesogenic compounds whose mesogens are of aromatic ester or amide type having a trifluoromethyl $(CF_3)$ substituent at the para-position of each terminal phenolic rings were prepared and their liquid crystalline properties were studied by differential scanning calorimetry (DSC) and on a cross-polarizing microscope. The compounds have two identical mesogenic units bracketing a central decamethylene spacer. Trifluoromethyl group appears to favor the formation of smectic phases when it is attached to a phenoxy or anilide terminal. Its group efficiency for mesophase formation seems to be inferior to other common substituents. A thermodynamic analysis of the phase transitions was made and the results were explained in relation to the structures of the compounds.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.9
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• pp.129-140
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• 2018

The purpose of this study was to reconsider existing hypotheses on the orinination and changes of changbang-anchogongs and their types and suggest an alternative hypothesis. The earliest changbang-anchogongs in $17^{th}$ century is presumed to originate as imitations of chungbang ppaelmoks for ornamental and reinforcing parts for changbangs. They were framed whole sides of buildings equally, and were used in small numbers of extant royal buildings and Buddhist halls. From late $17^{th}$ century, enlarged dragon shape changbang-anchogongs applied to Buddhist halls maily to decorate and strengthen front side of buildings. As a result of exchange between changbang-anchogongs and Ikgong type brackets, combined changbang-anchogongs in Buddhist halls were invented for stronger connection with upper bracketing units and have been spread during $18^{th}$ century. Danpyeongbang anchogongs were originated by the connection between short pieces of pyeongbangs and early type of anchogongs similar to ppaelmoks. They belong to minority subtype, but were drawn in illustrations by mistake, as parts of main halls of royal palaces from $19^{th}$ century, because of painter's confusion about new techniques for changbang-anchogongs. Combined changbang-anchogongs for royal buildings were presumed to be invented in 1790s by stimulation from a Buddhist hall related to royal tomb. However, unlike Buddhist precedence, they were used to reinforce and decorate whole sides, even corners, of buildings, and their frameworks and shapes were imported from Daeryang-anchogongs at flanks of ritual halls in royal tombs and royal shrines from $17^{th}$ century.