• Title/Summary/Keyword: 정근해

Search Result 1,417, Processing Time 0.03 seconds

Synthesis and Solution Properties of Water Soluble Polyester for Metal-Working Fluids (II) (금속가공유용 수용성 폴리에스테르의 합성 및 용액특성(II))

  • Yoon, Yoo-Jung;Kim, Young-Wun;Chung, Keun-Wo;Hwang, Do-Huak
    • Applied Chemistry for Engineering
    • /
    • v.16 no.6
    • /
    • pp.834-841
    • /
    • 2005
  • Polyethylene glycol esters (PEG-esters) were synthesized by condensation reaction of dicarboxylic acid such as adipic acid and sebacic acid and several PEGs. The PEG-esters were analyzed by FT-IR, $^1H-NMR$ and HPLC for structure analysis, and by GPC for molecular weight. Through the analysis of surface tension, critical micelle concentration (CMC), aluminum contact angle of water solution containing the PEG-ester, the synthetic PEG-esters are proven to exhibit surfactant properties. The surface tension ranged from 45 to 50 dyn/cm depended on the concentration and structures of the PEG-esters. The surface tension of PEG-esters with sebacic acid moiety and short polyoxyethylene unit resulted in lower value than that of PEG-ester with adipic acid moiety and long polyoxyethylene unit. The CMC of water solution containing 2.5 wt% PEG-ester with sebacic acid moiety estimated at $0.9{\times}10^{-5}{\sim}5.3{\times}10^{-3}mol/L$ depended on the structures of PEG-esters. The CMC of PEG-esters with long polyoxyethlene unit showed a higher value than that of PEG-esters with short polyoxyethylene unit. Meanwhile, the CMC of PEG-esters with adipic acid moiety was not distinct due to their high hydrophilic character. As the results of contact angle and cutting time aginst aluminum, the contact angle ranged from $45^{\circ}$ to $53^{\circ}$ depended on the concentration of PEG-esters. The cutting time of aluminum showed the shortest value at CMC, but the longest value above CMC. This fact indicates that the CMC of PEG-esters is a very important factor in drilling aluminum.

A Study on The Preparation of Poly(alkyl methacrylate-co-maleic anhydride) as Cold Flow Improvers for Biodiesel Fuels (바이오디젤용 저온 유동성 향상제로서의 폴리 (알킬메타크릴레이트-공-무수말레인산) 제조 연구)

  • Hong, Jin-Sook;Chung, Keun-Wo;Kim, Young-Wun;Kim, Nam-Kyun;Im, Dae-Jae
    • Applied Chemistry for Engineering
    • /
    • v.23 no.2
    • /
    • pp.232-240
    • /
    • 2012
  • Bio-diesel (BD) is the mono alkyl esters of long chain fatty acids derived from renewable feed stocks like vegetable oils or animal fats. Bio-diesel shows poorer fuel properties than that of diesel fuel in a cold condition. For the diesel fuel, many cold flow improvers have been developed; however, since primary ingredients of bio-diesel are different from those of the diesel fuel, there is a limit to the cold flow improvement when the same cold flow improvers are added to bio diesel. In this study, to improve low temperature properties of bio-diesel, we developed a cold flow improver using an alkyl methacrylate monomer, prepared via ester reaction, and maleic anhydride and also conducted a ring opening reaction using amine. We characterized the products using $^1H-NMR$, FT-IR and GPC methods. In addition, the cold flow improvements of the products in Soybean BD and Palm BD in the concentration rage of 1000~10000 ppm were investigated. It was found that the addition of LMA2SMA6MA2-C8A in Soybean BD improved the pour point by $12.5\;^{\circ}C$.

Quality Characteristics of High and Low Grade Hanwoo Beef During Storage at $1^{\circ}C$ (고급 및 저급 한우육의 저장중 품질 특성)

  • Jeong, Geun-Gi;Park, Na-Young;Lee, Shin-Ho
    • Korean Journal of Food Science and Technology
    • /
    • v.38 no.1
    • /
    • pp.10-15
    • /
    • 2006
  • Quality changes of first grade Hanwoo beef were compared with those of third grade Hanwoo beef to investigate effect of initial raw meat quality on maintenance of meat quality during storage for 28 days at $1\;{\pm}\;1^{\circ}C$. Crude fat content of first grade meat was higher, whereas water content was lower, than those of third grade meat. Total bacterial counts of first and third grade beef packaged with polyethylene for 21 days storage at $1\;{\pm}\;1^{\circ}C$ were 106 and $108\;CFU/cm^2$, respectively. Volatile basic nitrogen (VBN) value of first grade meats was lower than that of third grade meat during storage for 28 days at $1\;{\pm}\;1^{\circ}C$. Drip loss percents of first and third grade meats were 4.19 and 6.06% during 14 days storage at $1^{\circ}C$, respectively. L, a, and b values decreased gradually during storage regardless of meat grade, with a value of first grade meat being higher than that of third grade meat at early stage of storage at $1^{\circ}C$.

Effect of Fermented Anchovy Extracts on the N-methyl-N'-nitro-N-nitrosoguanidine-Induced Mutagenicities (멸치젓갈추출물이 돌연변이 유발에 미치는 영향)

  • Jung, Keun-Ok;Kang, Kap-Suk;Park, Kun-Young
    • Korean Journal of Food Science and Technology
    • /
    • v.32 no.6
    • /
    • pp.1426-1432
    • /
    • 2000
  • The effects of raw anchovy, salted raw anchovy (20% salt+anchovy), 6- and 12-month fermented anchovy (20% salt added) on the N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced mutagenicities were evaluated using Salmonella assay and the SOS chromotest. The methanol extracts from raw, salted and the fermented anchovy (FA) sample increased the revertants of Salmonella typhimurium TA100 at the level of $0.125{\sim}5\;mg/plate$ in Ames test. The salted raw anchovy extract induced the largest number of the revertants. All the FA extracts had comutagenic effect on the MNNG. Twelve-month FA juice exerted the lowest comutagenic activity among the FA samples. The comutagenicity of 12-month FA was due to the synergistic effect of salt and histidine which teem in FA. Thus the Ames test using histidine requiring mutant, S. typhimurium, is not appropriate to determine the mutagenicity of FA which is rich in histidine. In SOS chromotest using E coli, raw, salted and fermented anchovy extracts did not show any mutagenicity in the absence of MNNG. The raw and fermented anchovy samples blocked the SOS response of E. coli PQ37 induced by MNNG, while raw salted anchovy increased the SOS induction factor. Twelve-month FA juice showed higher antimutagenic effects than 6-month FA samples (both solid and liquid). The ripened (12-month) FA along with raw anchovy in the SOS chromotest exhibited antimutagenic activity.

  • PDF

Hangul Bitmap Data Compression Embedded in TrueType Font (트루타입 폰트에 내장된 한글 비트맵 데이타의 압축)

  • Han Joo-Hyun;Jeong Geun-Ho;Choi Jae-Young
    • Journal of KIISE:Software and Applications
    • /
    • v.33 no.6
    • /
    • pp.580-587
    • /
    • 2006
  • As PDA, IMT-2000, and e-Book are developed and popular in these days, the number of users who use these products has been increasing. However, available memory size of these machines is still smaller than that of desktop PCs. In these products, TrueType fonts have been increased in demand because the number of users who want to use good quality fonts has increased, and TrueType fonts are of great use in Windows CE products. However, TrueType fonts take a large portion of available device memory, considering the small memory sizes of mobile devices. Therefore, it is required to reduce the size of TrueType fonts. In this paper, two-phase compression techniques are presented for the purpose of reducing the sire of hangul bitmap data embedded in TrueType fonts. In the first step, each character in bitmap is divided into initial consonant, medial vowel, and final consonant, respectively, then the character is recomposed into the composite bitmap. In the second phase, if any two consonants or vowels are determined to be the same, one of them is removed. The TrueType embedded bitmaps in Hangeul Wanseong (pre-composed) and Hangul Johab (pre-combined) are used in compression. By using our compression techniques, the compression rates of embedded bitmap data for TrueType fonts can be reduced around 35% in Wanseong font, and 7% in Johab font. Consequently, the compression rate of total TrueType Wanseong font is about 9.26%.

Distribution of Vascular Plants at Five Islands (Jisimdo, Naedo, Yoondoldo, Songdo, Galdo) in East Hallyeohaesang National Park (한려해상국립공원 동부지역(지심도, 내도, 윤돌도, 송도, 갈도)의 관속식물상)

  • Park, Sam-Bong;An, Hyeon-Cheol;Cho, Hyeon-Seo;Choo, Gab-Chul;Shin, Hyun-Soo;An, Jong-Bin;Park, Jeong-Geun;Ngondya, Issakwisa Bernard;Kim, Han-Jin
    • Journal of agriculture & life science
    • /
    • v.46 no.5
    • /
    • pp.11-23
    • /
    • 2012
  • This study was conducted to investigate the distribution of vascular plants in five islands of Jisimdo, Naedo, Yoondoldo, Songdo and Galdo in East Hallyeohaesang National Park. The Islands were surveyed from 2010 to 2011. The flora was classified to as: Jisimdo, 246 taxa; 85 families, 195 genus, 219 species, 3 subspecies, 24 varieties and 2 forma. Naedo, 143 taxa; 72 families, 127 genus, 131 species, 12 varieties. Yoondoldo, 84 taxa; 56 families, 73 genus, 219 species, 1 subspecies, 10 varieties. Songdo, 70 taxa; 33 families, 63 genus, 64 species, 6 varieties and Galdo, 93 taxa; 47 families, 84 genus, 84 species, 1 subspecies, 7 varieties, and 1 forma. Thus, a total of 380 taxa; 105 families, 272 genus, 334 species, 3 subspecies, 39 varieties and 4 forma were observed. A total of 8 and 6 taxa were found to be rare plants in surveyed areas and endemic to Korea, respectively. Distribution of floristic special plants in the surveyed area was divided into five classes (class I-V), 42 taxa; were in class I, 1 taxa; was in class II, 25 taxa; were in class III, 4 taxa; were in class IV and 4 taxa; were in class V. Total floristic special plants were 76 taxa.

A New Red Color Rose Cultivar "Red Charm" with Few Prickles and Resistance to Powdery Mildew (흰가루병 저항성 및 가시가 적은 적색 장미 신품종 "레드참")

  • Gi, Gwang-Yeon;Hwang, In-Taek;Cho, Kyung-Chul;Lee, Ya-Song;Na, Taek-Sang;Yun, Bong-Ki;Kim, Jung-Guen;Lee, Jae-Sin;Han, Tae-Ho
    • Korean Journal of Breeding Science
    • /
    • v.41 no.4
    • /
    • pp.616-619
    • /
    • 2009
  • A new standard rose cultivar "Red Charm" was bred from the cross between deep red standard cultivar "First Red" and light red standard cultivar "Cardinal" at the Jeollanamdo Agricultural Research and Extention Services (JARES). The cross was made in 2003 and, "Red Charm" was finally selected in 2008 after investigating characteristics for three times from 2007 to 2008. "Red Charm", a red standard cultivar has good flower shape and velvet flower color. The major characteristics of this cultivar are on average $119.3stems/m^2/year$ in yield, 69.5 cm in length of cut flower, 10.3 cm in flower diameter, 36.9 in petal number, and 9.8 days in vase life. This cultivar can be propagated by both cutting and grafting. The consumer's preference of this cultivar, "Red Charm" is relatively higher than that of control cultivar, "Red Velvet".

Forest Structure of Jisimdo Hallyeohaesang National Park (한려해상국립공원 지심도의 식생구조)

  • Ahn, Hyun-Chul;Kim, Jeong-Woon;Choo, Gab-Chul;Shin, Hyun-Soo;Park, Sam-Bong;An, Jong-Bin;Park, Jeong-Geun;Ngondya, Issakwisa Bernard
    • Journal of agriculture & life science
    • /
    • v.46 no.3
    • /
    • pp.27-36
    • /
    • 2012
  • The purpose of this study was to investigate the structure of the vegetation on the trail of Hallyeo Marine & Coastal National Park. Twenty six $10{\times}10m$ plots were established along the Jisimdo trail. The vascular plants were surveyed from March 2011 to October 2011. Camellia japonica was a major woody species in the study area, while Pinus thunbergii and Zanthoxylum ailanthoides were co-dominant tree species. There were positive correlations between Distylium racemosum and Ligustrum japonicum var. japonicum; Callicarpa japonica var. luxurians and Eurya japonical; Actinodaphne lancifolia and Cinnamomum japonicum; A. lancifolia and Machilus japonica. Positive correlations were found between A. lancifolia and P. thunbergii; Z. ailanthoides and C. japonicum. Species diversity (H') was ranged from 0.51907 to 1.0217, and was relatively low compared to those of same national parks. 10 populations of Milletia japonica which are rare and endemic species, were recorded from the list of rare and endemic species of the Ministry of Environment near by ammo dumps, this study recommend the long term habitat monitoring of the species.

Effects of Stock Plant Management and Foliar Spray of GA on the Flower Quality in Hydroponically Grown Chrysanthemum cv. 'Shinma' (모수포 관리 및 지베렐린 처리가 국화 '신마'의 절화품질에 미치는 영향)

  • Hwang, In Taek;Cho, Kyung Chul;Kim, Hee Gon;Ki, Gwang Yeon;Yoon, Bong Ki;Kim, Jung Guen;Han, Tae Ho;Lee, Jeong Hyun;Yoo, Yong Kweon
    • FLOWER RESEARCH JOURNAL
    • /
    • v.18 no.4
    • /
    • pp.256-260
    • /
    • 2010
  • This study was carried out to investigate effects of stock plant management and foliar spray of GA on the flower quality in hydroponically grown chrysanthemum 'Shinma'. In the growth and development as affected by stock plant management, cut flower length, petal number and cut flower weight were the best in the plot of long day and chilling treatment showed 114 cm, 298 and 102 g, respectively. Chlorophyll content(SPAD-value) was the highest in the plot of foliar spray of diluted Molbia(1 : 500). Flower quality according to concentration and spray time of gibberellin showed a different pattern. Cut flower length was the longest in the plot of solution diluted to 1 : 1,000 spraying before flowering at 60 days, petal number was the most in 1 : 500 at 60 days, and cut flower weight was the heaviest in 1 : 2,000 at 60 days, respectively. However, peduncle length was tended to be elongated with foliar spray of gibberellin solution diluted to 1 : 500 or 1 : 1,000 before flowering at 45 days.

A New Rose Cultivar 'Innocence' with White-pink Flower for Bouquet (부케용 백분홍색 장미 「이노센스」 육성)

  • Gi, Gwang-Yeon;Hwang, In-Taek;Cho, Kyung-Chul;Kim, Jung-Guen;Yoon, Bong-Ki;Choi, Kyong-Ju;Lee, Jae-Sin;Han, Tae-Ho
    • FLOWER RESEARCH JOURNAL
    • /
    • v.19 no.4
    • /
    • pp.251-254
    • /
    • 2011
  • A new standard white-pink flower rose cultivar 'Innocence' was bred from the cross between white standard cultivar 'Juvena' and green-white standard cultivar 'Green Success' at the Jeollanamdo Agricultural Research and Extension Services (JARES). The cross was made in 2001 and, 'Innocence' was finally selected in 2006 after investigating characteristics for three times from 2004 to 2006. 'Innocence' a white-pink standard cultivar has good flower shape with few prickles. The major characteristics of this cultivar were $118.7stems{\cdot}m^{-2}$ in year yield, 68.0 cm in length of cut flower, 10.9 cm in flower diameter, 34.4 in petal number, and 10.7 days in vase life. This cultivar can be propagated by both cutting and grafting. The consumer's preference of this cultivar was relatively higher than that of control cultivar, 'Rose Yumi'.