• Applied Chemistry for Engineering
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• v.9 no.6
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• pp.822-828
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• 1998

Binary system of water and polyoxyethylene dodecyl ether, $C_{12}H_{25}(OCH_2CH_2)nOH$, have been studied by $^1H$ NMR techniques. For n=5($C_{12}EO_5$) and n=8($C_{12}EO_8$), the self-diffusion coefficients of nonionic surfactants in the isotropic phase($L_1$) have been measured by using pulsed field gradient technique for a range of temperature and concentrations. In addition the line widths of the different proton signals have been monitored, and samples of some liquid crystalline characteristic were also studied. Dramatic Broadening of the methylene signals of the alkyl($C_{12}H_{25}$) chain is observed as the hexagonal liquid crystalline phase is approached in the $C_{12}EO_5-$water system, while only small broadening is observed in the $C_{12}EO_8-$water system. It was shown that there was a growth of $C_{12}EO_5$ micelles to rods with increasing concentrations, while the $C_{12}EO_8-$ micelles at low temperature remain small in the concentration range. The self-diffusion coefficients of the surfactants decrease rapidly with increasing concentration until a minimum is reached after which there is slow increase. The location of the minimum point occurs at lower concentrations the temperature is close to the cloud point, where the system separate into two isotropic phase. In the line width studies, broadening is found at a certain temperature interval when the concentration is increased in the $C_{12}EO_5$ system. The results indicate that the surfactant aggregates grow in size at the cloud point is approached. The aggregates seem to be flexible and probably not to be of a definite shape close to the cloud point. In the $C_{12}EO_8$ system, the micelles are much less affected by an increase in temperature and micellar growth can't be unambiguously established. The methylene signals of the ethylene oxide moieties consistantly show narrower $^1H$ signals, showing that in the aggregates they are less ordered than the chain methylenes. The various changes in aggregate size and shape are correlated with the stability ranges of the isotropic and liquid crystalline phases according to phase diagrams from the literature. Both aggregate size and phase structure are in qualitative agreement with concentration based on the effective shape of the molecules at different temperature and concentration.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.1
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• pp.31-43
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• 2014

The purposes for this research were to find the correct building background of Jondeokjeong(尊德亭) in the rear garden of Changdeok Palace(昌德宮) based on the historical facts for the area of Jondeokjeong and investigate the internal theory of construction through the metaphysical consideration. The results were as follows. 1. Building background of Jondeokjeong was related to Sohyunseja(昭顯世子) and Bongrimdaegun(鳳林大君) as forms of rear garden where was not built in the area of Jondeokjeong, bamboo pavilion, hexagonal pavilion, octagonal pavilion, etc. They were built two or three times after returning of Sohyunseja and Bongrimdaegun from China, and the area of Jondeokjeong was continuously developed by building Chunhyanggak(天香閣), Mangchunjeong(望春亭) and Cheoknoidang(滌惱堂) after Hyojong(孝宗) succeeded the royal authority of Hyunjong(顯宗) who was born in Shenyang(瀋陽) and hung a signboard of Jondeokjeong after then, etc. 2. Dazhengjeon(大政殿) of Shenyang Palace(瀋陽故宮, 1625) played the roles of major hall, Jeongjeon(正殿) which held national big events as a one-storied building with two piles of roof similar with Jondeokjeong (1644). Also, it was the building encountered when Sohyunseja and Bongrimdaegun participated in breakfasts held in the palace or banquets supervised by a king, so building background of Jondeokjeong was judged to be related with Dazhengjeon. 3. In consideration of characteristics which are shown commonly in Jondeokjeong and Dazhengjeon, relations of two buildings were verified and characteristics of Jondeokjeong were examined. First, dragon which is representatively symbolizing royal authority was formed. Therefore, Jondeokjeong was judged as a garden building which purposes were to obtain and train natural reasons, govern the nation and let people comfortable. Second, the purposes of sun dial, Ilyoungdae(日影臺) were judged to examine the accurate time and express appropriateness of the king. Third, Taechungmun(太淸門) around there is related to Samcheong(三淸) of Taoism and judged to be caused by floral wall and secular happiness accomplishment for king's longevity without disease. Fourth, for building style, one-stories pavilion of duplicated roof and building with only cylinder were to king's embodiment of supporting the sky and governing the nation.4) 4. By examining the differences between Jondeokjeong and Dazhengjeon, Jondeokjeong's own characteristics were considered. First, constructive characteristics of Jondeokjeong were changed by existing of pond and it was changed for characteristics, location and function of pavilion built in the garden while accepting oversea culture and embodied by absorbing to Joseon culture. Second, the appearance of the pond in Jondeokjeong was shown as the situation that half moon typed pond with the form of young moon is full by stream to the East. It was to express movement of moon which was always changed through the form of pond and stream of water iconographycally and it was considered as an imaginary environment method of the period.