• Elastomers and Composites
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• v.49 no.3
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• pp.181-190
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• 2014

Melt grafting of itaconic acid (IA) onto an ethylene-propylene-diene terpolymer (EPDM) with various organic peroxide initiators was performed. Finding the optimum mixing conditions and concentration of ingredients is critical for effective grafting and optimum properties of grafted materials. This study focused on the effects of mixing conditions (temperature and time), initiator type/concentration and monomer concentration on the grafting degree and efficiency, melt flow index, and gel content of EPDM-g-IA. The initiator, 2,5-dimethyl-2,5-di(tert-butyl peroxy)-hexane (T-101), appeared to meet for the best grafting degree (1.91%). The grafting degree increased markedly by increasing the amounts of monomer IA and initiator T-101. The grafting degree also increased by increasing mixing temperature and time. The optimum monomer and initiator concentrations and reaction temperature and time were found to be about 5wt%/0.05wt% and $160^{\circ}C$/15min, respectively. It was found that the physical properties of EPDM-g-IA were higher than those of the pristine EPDM.

• Korean Journal of Medicinal Crop Science
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• v.6 no.3
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• pp.198-203
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• 1998

This experiment was conducted to determine the effect of different size of divided crowns used as planting material on the growth characteristics, yield and quality of Paeania lactiflora Pallas (P. lactiflora Pallas). The ratio of sprouting, rooting, and growth of above-ground parts increased with the increase of crown size. The root yields of under-ground parts from different size of divided crown were 2,674kg/10a for large size and 2,304kg/10a for medium size and the yield index was improved by 39% and 30%, respectively, compared to 1,921kg/10a in small size. Commodity ratio of roots over 10mm in diameter were higher for large and medium size crown: index increased by 26 % and 11 %, respectively, compared to 1,406kg/10a in small size. Income analyzed by crown size was \ 1,133,000 per 10a at the use of small crown size but income were increased 25 % and 48 %, respectively. by using medium and large size crown as compared with small crown.

• Korean Journal of Medicinal Crop Science
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• v.6 no.3
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• pp.193-197
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• 1998

This experiment was carried out to determine the proper time for flower bud removing to improve growth, yield and paeoniflorin content of root in peony(Paeonia lactiflora Pallas). The flower buds removement caused short stem length by $7{\sim}9cm$ compared with control, but number of stem and stem diameter were similar to that of control. The number of root, fresh root weight and paeoniflorin content in peony increased when their flower buds were removed at earlier stages. The root dry weight was highest of 1.647kg/10a, and increased by 27% compared with control when their flower buds were removed at early stage (bud diameter was less than 10mm). The root dry weight increased by 13% and 10%, respectively. when their flower buds were removed prior to flowering and at flowering stage. Paeoniflorin content in leaf was higher than that in stem, and was higher at early stage. Leaf and stem showed higher paeonif1orin content when their flower buds were removed.

• Korean Journal of Medicinal Crop Science
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• v.6 no.3
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• pp.188-192
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• 1998

The correlations between growth charateristics and root yield were investigated in 74 peony lines collected from chief producing place in Korea. Among these peony lines, single flower type was 61% and the rest were double type. And pink flower was in majority. Stem length, stem diameter and number of stem per plant were $50{\sim}60cm$, $7{\sim}8mm$ and $5{\sim}6$, respectively. Generally, disease tolerance and root yield were better in single flower type peonies than double type. Among single flower type peonies, the correlation coefficients between each characteristics and root yield were as follows : number of stem $(0.676^{**})$, number of roots $(0.646^{**})$, stem length $(0.617^{**})$, root diameter $(0.590^{**})$ and root length $(0.443^{**})$. Correlation between root yield and paeoniflorin content was highly significant $(0.383^{**})$ among single flower type peonies and significant $(-0.382^*)$ among double flower type peonies. Correlation between stem diameter and root yield was not significant (0.066).

• Korean Journal of Medicinal Crop Science
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• v.5 no.4
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• pp.318-324
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• 1997

When Bupleurum falcatum field was irrigated three times with 20mm at intervals of 10days after sowing, establishment was inproved (64%) and root yield increased to 58kg/10a. And in early growing stage, 30mm irrigation six times at intervals of 10days increased the number of harvested plants per square meter and resulted in yield increase by 26% over yield from natural plot. 20mm irrigation in sowing time at intervals of 10days and 30mm irrigation in early growing stage at intervals of 10days kept adequate soil moisture content (soil moisture tension: $0.39{\sim}0.49bar)$ and resulted in better establishment, growth and yield of Buleurum falcatum.

• Korean Journal of Medicinal Crop Science
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• v.4 no.4
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• pp.308-313
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• 1996

The appropriate drying method in medicinal compounds and color of peony root was that predrying at briquet fire $(40{\sim}60^{\circ}C)$ for 6 hours or more, and then hot air drying at $40^{\circ}C$ during 60 hours. But this method needs too much time in drying. And the method that drying at $40^{\sim}C$ with hot air drying has bad result in color. In case Peony was seld by cutting product, before cutting, the Peony root was retted for 30 min. and sealed for 12 hrs. is good for drying time, Peoniflorin content and commodity.

• Korean Journal of Medicinal Crop Science
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• v.10 no.1
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• pp.24-28
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• 2002

Effect of pretreatment processing (peeling time, drying temperature, sample type) on the quality of hot air drying peony roots was investigated. Peony roots were peeled for 0, 10, 20, 30, 60, 90 and 120 minute in the peeling machine after water washing. Sample types were whole or cut (thickness of 3mm). Temperatures of hot air drying were 30, 40, 50 and $60^{\circ}C$ The level of water contents in dried sample was $14{\sim}15%$. Drying time was muth reduced as the peeling time, cutting sample types and higher temperature. Contents of paeoniflorin were maintained highest amount (3.48%) in the non-peeling cut sample dried at $30^{\circ}C$ and lowest amount (2.29%) in the 120min-peeling whole one dried at $60^{\circ}C$. Skin color of dried peony roots was heavily discolored in the sample of non-peeling whole type dried at $60^{\circ}C$ and the color was dark brown $({\Delta}E\;was\;46.1)$. When considering shortening of drying time, preservation of active compounds and maintenance of color, the best pretreatment method of drying in peony roots was non-peeling, cut type processing.

• Membrane Journal
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• v.28 no.5
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• pp.307-319
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• 2018

Ion-exchange membrane (IEM) has fixed charge groups and is a separation membrane which is capable of selectively transporting ions of the opposite polarity. Recently, the interest in IEMs has been increasing as the importance of the desalination and energy conversion processes using them as the key components has increased. Since the IEMs determine the efficiency of the above process, it is necessary to improve the separation performance and durability of them and also to lower the expensive membrane price, which is a hindrance to the widening application of the IEM process. Therefore, it is urgent to develop high-performance and low-cost IEMs. Among various types of IEMs, pore-filled membranes prepared by filling ionomer into a porous polymer substrate are intermediate forms of homogeneous membranes and heterogeneous membranes. The production cost would be cheap like the case of heterogeneous membranes because of the use of inexpensive supports and the reduction of the amount used of raw materials, and at the same time, they exhibit excellent electrochemical characteristics close to homogeneous membranes. In this review, major research and development trends of pore-filled IEMs, which are attracting attention as high-performance and low-cost IEMs, have been summarized and reported according to the application fields.

• Journal of the Mineralogical Society of Korea
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• v.18 no.3 s.45
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• pp.165-181
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• 2005

The granitic rocks distributed in the southern part of the Yangsan Fault are classified into five distinct rock facies based on the field relation, petrography and geochemical characteristics. These five different rock facies can be grouped into two considering their origins. Group I, which reveals various evidences of magma mixing, includes three rock facies of granodiorite, enclave-rich porphyritic granite, and enclave-poor porphyritic granite. Group H intruding Croup I includes equigranular granite and micrographic granite with no evidence of magma mixing. It is suggested that the distinctively different trace element and isotopic chemistries between group I and II, support evolution from the different parental magma. It is suggested that the three rock facies in group I were generated by different degrees of magma mixing in addition to fractionation of plagioclase. MMEs experienced fractionation of biotite. The two facies in group H seem to have been generated from different parent magma from group I and evolved by fractionation of K-feldspar. The Rb-Sr whole-rock ages of the group I rocks yield $59.2\~58.9Ma$, and those of the group II rocks give 53. $3\~51.7Ma$, regardless of their distribution whether they occur in the eastern or western parts of the Yangsan Fault. Based on Sm-Nd isotope compositions, depleted mantle model ages $(T_2DM)$ of the group I range $0.8\~0.9Ga$, while those of the group II$0.6\~0.7Ga$.

• The Journal of the Korea Contents Association
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• v.18 no.1
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• pp.289-304
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• 2018

The fandom phenomenon of political emotion originated from ideological conflicts between the conservative and the progressive amplifies social conflicts in South Korea in interpreting and accepting films as culture media. The purpose of this paper is to examine why the structure of political consciousness in South Korea is fandomized, what is the acceptance of cinema at the center of the controversy of political ideology, and what is the desirable attitude of film reception. I conducted a discourse analysis that closely examined the debates and articles on the internet regarding ,(2013) and ,(2014) which were controversial in terms of conservatism and progressivism. As a result, First, while Korean society has not constituted a consensus on modern and contemporary history, it has easily led the acceptance of cinema to the controversy surrounding the political ideology. Second, the failure of constructing consensual memories of modern and contemporary history has made the conservative and the progressive not acknowledge the other's achievements. Third, film interpretation and meaning production are ultimately the roles of the audience, and on interpretation, diversity should be respected but conformity would be rejected. Film acceptance and interpretation should focus on rational awareness of social reality and would reflect on the social ideal objectively.