• 제목/요약/키워드: Chonju

검색결과 316건 처리시간 0.024초

올리고 부틸렌 테레프탈레이트와 6-아미노 카프론산으로부터 포리에스테르 아미드의 합성 (Preparation of Polyesteramide from Oligobutylene Terephtahlate and 6-amino Caproic Acid)

  • Cho, Soon-Chae;Choi, Doo-Jin;Kim, Seon-Ho;Rhee, Johng-Moon;Pak, Pyong-Ki;Ahn, Jong-Yeol;Kim, Young-Gil
    • 한국염색가공학회지
    • /
    • 제3권1호
    • /
    • pp.17-24
    • /
    • 1991
  • Polyesteramide(PEA) has been synthesized with different molar ratio of 6-aminocaproic acid(ACA) and oligo butylene terephthalate(OBT) prepared from Dimethyl terephthalate(DMT) and 1, 4-butanediol(BD) by the melt polymerization. Oligomer and polymer molecular structure were characterized by IR spectra, H'-NMR spectra. Also the thermal properties were examined by thermogravimetric analysis(TGA) and differential scanning calorimetry(DSC). DSC and TGA results exhibited that the$ T_m$ s were detectable in the vicinity of $170-220^{\circ}C$ and the Ta's were detectable in the vicinity of $380-390^{\circ}C$ . X-ray diffraction analysis results show that the synthesized polyesteramide has high degree of crystallinity.

  • PDF

대장암에서 장세척물의 세포학적 소견 (Cytologic Findings of Colon Lavage Fluid in Colon Cancer)

  • 이혜경;주명진;이광민;정동규;최용우
    • 대한세포병리학회지
    • /
    • 제7권1호
    • /
    • pp.103-106
    • /
    • 1996
  • Although exfoliative colonic cytology for the diagnosis of colorectal cancer has been largely abandoned due to the widespread use of colonoscopy, some authors still insiston the usefulness of colon lavage fluid. We tried evaluating the diagnostic feasibility of colon lavage fluid cytology using an orally administered balanced electrolyte solution. We collected colon lavage fluids in 106 patients prior to colonoscopy and reviewed the slides. Cytologic examination revealed neoplastic cells in 7 of 16(44%) cases of endoscopically proven adenocarcinoma patients. Therefore, we thin cytologic study of colon lavage fluid may be considered as one of the noninvasive diagnostic tools in colorectal cancer.

  • PDF

단삼(丹蔘) 엑기스의 간보호작용 (Hepatoprotective Activity of Salviae miltiorrhizae Radix Extract)

  • 은재순;임종필;박이규;염정렬;최동성;안문생
    • 생약학회지
    • /
    • 제22권2호
    • /
    • pp.95-100
    • /
    • 1991
  • Salviae miltiorrhizae(SM) Radix extract increased $[^3H]-thymidine$ incorporation into rat hepatocytes at the concentration ranging from $5{\times}10^{-5}\;to\;5{\times}10^{-1}mg/ml$. It decreased the activities of s-GOT and s-GPT in cirrhotic rats induced by $CCl_4$, TAA and D-GalN, respectively and reduced the sleeping time induced by hexobarbital in $CCl_4$,TAA and D-GalN intoxicated mice, respectively. SM extract shortened the half-life of sulfobromophthalein in $CCl_4$ intoxicated rats.

  • PDF

전주시 하천의 BOD, COD,총질소, 총인에 대한 수질현황 및 오염원 (The State and Sources of Contamination with BOD, COD, T-N and T-P in Stream Within Chonju City)

  • 오창환;이지선;김강주;황갑수
    • 자원환경지질
    • /
    • 제35권1호
    • /
    • pp.43-54
    • /
    • 2002
  • 전주시내에는 전주천과 삼천천이 흐르고 있으며 그 주변에는 여러 오염원이 분포하고 있다. 삼천천은 고사평 쓰레기 매립장에서 전주천과 합류하고 전주천은 최종적으로 만경강에 합류된댜. 전주천과 삼천천은 BOD, COD, 총질소, 총인에 대해서 오염되어 있으녀 전반적으로 상류에서 하류로 가면서 오염정도가 증가하는 경향을 보여준다. 전주천 하류에서 COD, 총질소, 총인 양은 호소기준 5급수 상한값의 수배에 해당된다. 이는 전주식 하수가 BOD, COD, 총질소, 총인의 주 오염원임을 지시한다. 고사평쓰레기 매립장은 BOD와 COD의 오염원일 가능성이 높다, 촟ㅇ질소는 상류부터 상댱히 오염되어 있기 때문에 농업활동에 의한 오염 영햐도 큰 것으로 생각된다. 전주천은 만경강의 BOD, COD, 총질소, 총인 오염에 중요한 영향을 미치고 있다. 전주천 외에도 전주 하류의 만경강 지류들은 BOD,COD, 총질소, 총인에 의해 만경가응ㄹ 오염시키고 있으며 특히 익산천은 주 오염원이다. 199년 8월의 오염부하량을 실제 유량과 수질 분석치를 이용해 계산해 본 결과 전주천 유입 이전의 만경강인 고산천으로부터 유입되는BOD(0.49 ton/day), COD(0.86 ton/day), 총질소(1.61 ton/day), 총인(0.01 ton/day)에 비해 전주천을 통하여 유입되는 BOD, COD, 총질소, 총인이 각각 약 5배, 7배, 7배, 36배 가량 높았으며 익산천을 통하여 유입되는 BOD, COD,총질소, 총인이 각각 약 5배, 7배, 7배, 36배 가량 높았으며 익산천을 통하여 유입되는 BOD, COD, 총질소, 총인은 각각 약 13배, 10배, 10배, 147배 가량 높았다.

전주시 하천의 중금속과 음이온에 대한 수질현황 및 오염원 (The State and Sources of Contamination with Heavy Metals and Anion in Stream Within Chonju City)

  • 오창환;이지선;김강주;정성석;황갑수;이영엽
    • 자원환경지질
    • /
    • 제34권1호
    • /
    • pp.89-104
    • /
    • 2001
  • 전주시내에는 전주천과 삼천천이 흐르고 있으며 그 주변에는 여러 오염원이 분포하고 있다. 삼천천은 고사평 쓰레기 매립장에서 전주천과 합류하고 전주천은 최종적으로 만경강에 합류된다. 본 연구에서는 중금속과 음이온에 대한 전주천과 삼천천의 오염현황과 오염원 그리고 이들 하천이 만경강 수질에 미치는 영향을 연구하였다. 전주천과 삼천천에 대한 연구를 위한 시료채취지점을 선정하기 위하여 하천 구간을 오염정도가 다를 것으로 예상되는 여러 구간으로 나누고 각 구간에서 난수표를 이용하여 대표적인 시료를 채취하는 층화랜덤추출 방법을 이용하였다. 연구결과 시료 채취 당시 전주천과 삼천천은 중금속이나 음이온에 대해서 전반적으로 음용수 기준치 이상으로 오염되지는 않았다. 그러나 중금속과 음이온은 현재 하천으로 계속 공급되고 있으며 가뭄 동안에는 하천을 오염시킬 가능성이 있다. 본 연구에서 두 쓰레기 매립장은 Fe, Mn, Al, Zn, Cl ̄, SO$_4$$^{2-}$ , NO$^2$-N, NH$_3$-N, 그리고 미처리된 하수는 Al, Zn, Mn, Cl ̄, SO$_4$$^{2-}$ , NH$_3$-N, PO$_4$$^{3-}$ 의 오염원인 것으로 나타났다. 또한 전주천은 Fe, Mn, $Cl^{-}$, $SO_{4}^{2-}S$ 성분에 대한 만경강 오염에 중요한 영향을 미치고 있다.

  • PDF

황련과 감초의 수용성 혼합물로부터 얻어진 반응침전물의 세포독성 (Cytotoxicity of Reaction-Precipitate from Coptidis Rhizoma and Glycyrrhizae Radix Aqueous Mixture)

  • 은재순;조해전;양재헌;전훈;김영안
    • 생약학회지
    • /
    • 제25권4호통권99호
    • /
    • pp.356-362
    • /
    • 1994
  • The purpose of this research was to investigate the effect of reaction-precipitate from Coptidis Rhizoma and Glycyrrhizae Radix aqueous mixture(CGP) on the cytotoxicity. The effects of CGP on the growth of tumor cells, Balb/c 3T3 cell, mouse spleen cell and human lymphocyte were compared with those of berberine, glycyrrhizin and berberine glycyrrhizinate(BG), which were estimated by MTT colorimetric assay or cell counting. CGP, berberine and BG inhibited the growth of several tumor cells, such as Hep G2, A549, Raji, MCF-7, HeLa and KHOS-NP. Whereas, glycyrrhizin inhibited the growth of Raji and MCF-7, CGP did not affect on Balb/C 3T3 cells, mouse spleen cells and human lymphocyte at $10^{-6}{\sim}10^{-5}g/ml$. CGP increased the number of leukocyte in mice. This results indicate that CGP have the inhibitory action of the growth of human tumor cells, and the side effect of CGP is less than berberine and BG.

  • PDF

셀룰로오스계 폐기물의 재활용 ―II. 폐면으로부터 hydroxyethyl cellulose 제조― (Recycling of the Waste Cellulose ―II. Preparation of Hydroxyethyl Cellulose from Knit-Cotton-Waste―)

  • Lee, Sung Goo;Ihm, Sung Dam;Kim, Byung Suk;Mun, Sung Phil;Rhee, John Moon
    • 한국염색가공학회지
    • /
    • 제7권2호
    • /
    • pp.32-39
    • /
    • 1995
  • Various grades of hydroxyethyl cellulose (HEC, MS 0.65-3.20) were prepared throngh reaction of the knit-cotton-waste with ethylene oxide(EO). The knit-cotton-waste was composed of 98% of $\alpha$-cellulose and 2% of other components, and the cellulose was highly pure. The molar ratio of EO to knit-cotton-waste and that of NaOH to knit-cotton-waste, and the agitation speed were the important factors determining the molar substitution(MS) during the preparation of HEC. The MS of HEC was remarkably increased with increasing molar ratio of EO' to knit-cotton-waste. When the molar ratio of EO to knit-cotton-waste was 3.5, that of NaOH to knit-cotton-waste was 1.25, and agitation speed was 450rpm, it was possible to prepare HEC of MS 2.5. The structure and crystallinity of HECs prepared were determined by FT-IR and X-ray diffraction.

  • PDF

Organic Solvent and pH Induced Alteration of Product Specificity of CGTase

  • Park, Kyo-Sun;Oh, Hyun-Mi;Choe, Hui-Woog;Park, Chung-Ung;Lee, Kang-Min
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • 제3권2호
    • /
    • pp.78-81
    • /
    • 1998
  • Cyclodextrin glucanotransferase [CGTase, E.C.2.4.1.19] is an extracellular enzyme, which catalyzes he formation of ${\alpha}$-, ${\beta}$-, ${\gamma}$- CDs from starch. Their proportions of formations depend on enzyme sources and reaction conditions. To understand what determines the product specificity of CGTases, we examined the alteration of product specificity of CGTase from Bacillus macerans by organic solvent sand pH. At acidic pH range less than pH 6 where the enzyme was unstable, the ratio of ${\alpha}$-/ ${\beta}$-CD production was increased 4 times more than that at neutral pH range. As we increased the concentration of 2-butanol, ${\alpha}$-/ ${\beta}$-CD ratio was proportionally increased but / ratio remained constant. The ${\alpha}$-/ ${\beta}$-CD ratio of products was increased in the reaction media which yielded low products.

  • PDF

Modified CMOS Composite Transistors

  • Yu, Young-Gyu;Lee, Geun-Ho;Kim, Dong-Yong
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2000년도 추계종합학술대회 논문집(2)
    • /
    • pp.63-66
    • /
    • 2000
  • In this paper, we propose two new CMOS composite transistors with an improved operating region by reducing a threshold voltage. The proposed composite transistor 1 and 2 employ a P-type folded composite transistor and an electronic zener diode in order to decrease the threshold voltage, respectively. The simulation has been carried oui using 0.25$\mu\textrm{m}$ n-well process with 2.5V supply voltage.

  • PDF