RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제
      • 좁혀본 항목 보기순서

        • 원문유무
        • 음성지원유무
        • 원문제공처
          펼치기
        • 등재정보
          펼치기
        • 학술지명
          펼치기
        • 주제분류
          펼치기
        • 발행연도
          펼치기
        • 작성언어
        • 저자
          펼치기

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • SCOPUSKCI등재

        추황배(Pyrus pyrifolia Nakai cv. Chuhwangbae) 과피로부터 1종의 Sterol과 3종의 배당체 화합물의 단리·동정

        이유건(Yu Geon Lee1),조정용(Jeong-Yong Cho),이현주(Hyun Joo Lee),이용현(Yong Hyun Lee),이상현(Sang-Hyun Lee),한태호(Tae-Ho Han),김월수(Wol-Soo Kim),박근형(Keun-Hyung Park),문제학(Jae-Hak Moon) 한국식품과학회 2013 한국식품과학회지 Vol.45 No.5

        본 연구에서는 배의 유용성 증명을 위한 일환으로 배의 화학성분을 분자수준에서 밝히고자 하였다. 이에 배 과피 MeOH 추출물을 용매분획하여 얻은 EtOAc-산성 분획과 EtOAc-중성분획을 대상으로 Sephadex LH-20, silica gel, 그리고 ODS colmn chromatography와 HPLC를 이용하여 정제 및 단리하였다. 그 결과, EtOAc-산성 분획과 EtOAc-중성 분획으로부터 각각 2종씩의 화합물을 단리하였다. 단리된 화합물 1-4는 1H- 및 13C-NMR 분석을 통하여 각각 (S)-(+)-2-cis-abscisic acid O-β-D-glucopyranosyl ester (화합물 1), 1-[4-O-β-D-glucopyranosyl]phenyl ethanone(piceoside, 화합물 2), β-sitosterol (화합물 3), 그리고 β-sitosteryl 3-O-β-D-glucopyranoside (화합물 4)로 동정되었다. 단리된 3종의 배당체 화합물(화합물 1, 2, 4)들은 본 연구에 의해 배로부터 처음 동정되었으며, 화합물 3은 추황배로부터 처음 동정되었다. 본 연구결과가 배 함유 성분연구는 물론 배의 기능성 해명 연구에도 추후 중요한 기초자료로 활용되길 기대한다. We isolated and identified antioxidants from acidic and neutral ethyl acetate fractions of the peel of pear (Pyrus pyrifolia N. cv. Chuhwangbae). We isolated 4 compounds from the methanol extract, by using 3 different types of column chromatography (Sephadex LH-20, silica gel, and octadecylsilane) and preparative HPLC. We identified the isolated compounds as (S)-(+)-2-cis-abscisic acid O-β-D-glucopyranosyl ester (compound 1), 1-[4-O-β-D-glucopyranosyl]phenyl ethanone (picroside, compound 2), β-sitosterol (compound 3), and β-sitosteryl 3-O-β-D-glucopyranoside (compound 4) by nuclear magnetic resonance analysis. We are the first to report the identification of compounds 1, 2, and 4 from pear.

      • KCI등재

        단상 유도형 동기 전동기(LSPM)의 특성해석에 관한 연구

        정대성,김승주,이진헌,최재학,이주,Jung, Dae-Sung,Kim, Seung-Ju,Lee, Jin-Hun,Choi, Jae-Hak,Lee, Ju 한국조명전기설비학회 2007 조명·전기설비학회논문지 Vol.21 No.3

        가전분야에서의 전동기 효율향상을 통한 에너지 소비절감 효과는 상당히 크지만 이를 위한 전동기의 설계/해석 기술 확보가 아직은 미흡한 상태이다. 이에 따라 유도형 동기전동기가 제안되었지만, 유도형 동기 전동기는 유도전동기와 통기전동기의 특성을 동시에 가지고 있어, 해석 및 설계가 쉽지 않다. 따라서 본 논문에서는 기존의 냉장고 압축기용 전동기인 단상유도전동기를 대처할 수 있는 단상 유도형 동기전동기를 이용해 파라미터에 따라 특성이 어떻게 바뀌는가에 대해 서술하였다. 그에 따라 단상유도전동기의 정상상태 특성을 해석하고 제안모델의 성능을 기존모델과 비교하고 실험하여 해석결과의 신뢰성을 검증한다. 또한 본 논문에서는 제안모델의 기존 고정자 형상이나 권선 스팩을 유지하고 회전자의 형상이나 구조만을 변경시켜 성능향상을 도모하였다. 해석방법으로는 전자장 수치 해석적인 방법으로 널리 이용되고 있는 유한요소법(Finite Element Method : FEM)을 이용하였다. Electric motor efficient improvement from home appliance field is important to the effect reducing the energy consumption. But the electric motor design/analysis technology is still insufficient. Specially the electric motor design/analysis technology of satisfying characteristic of both the induction motor and the synchronous motor such as Line start permanent motor. Therefore the electric motor design/analysis technology is urgently demanded reliability. This paper proposes the sing1e-phase line-start permanent magnet motor to develop the motor it with be able to alternate the sing-phase induction motor it is a refrigerator compressor motor. The sing-phase induction motor is analyzed in the steady state. And we have a certification test to compare our single-phase line-start permanent magnet motor with the sing-phase induction motor. In order to improve the performance, the stator of the single-phase line-start permanent magnet motor is same as the stator of the sing-phase induction motor and changes the rotor form and has the permanent magnet. It used the Finite Element Method(FEM) which is widely used with electronic-magnetic field numerical analysis method.

      • KCI등재후보

        형광분광법에 의한 방향족 탄화수소의 동시정량

        이상학,손범목 한국환경과학회 2003 한국환경과학회지 Vol.12 No.1

        Synchronous spectrofluorimetry was carried out for the simultaneous determination of various polycyclic aromatic hydrocarbons(PAHs) in aqueous solution by fluorescence spectrometry have been studied. The optimal wavelength interval(Δλ) for synchronous spectra of acenaphthene, anthracene, benzo[a]anthracene, fluorene and pyrene were investigated in the presence of surfactants. The great enhancement of the fluorescence of these PAHs in Triton X-100 was obtained and optimal wavelength was 50 nm. The calibration curves in synthetic mixture solution of 5 PAHs were linear over the range from 1.0x10^-8M to 1.0x10^-4M. Under the optimal experimental conditions, the detection limits were 4.9x10^-9M, 7.0x10^-9M, 4.7x10^-9M, 1.6x10^-9M and 3.2x10^-9M for acenaphthene, anthracene, benzo[a]anthracene, fluorene and pyrene, respectively.

      • 디버링 작업을 위한 로봇 제어기 개발

        이중훈,박근우,이성학,이민기 國立 昌原大學校 産業技術硏究所 1999 産技硏論文集 Vol.13 No.-

        This paper presents the controller of a double parallel robot manipulator applied for deburring work. This is one of the least favored works because of dust, noise, vibration, and accidental injury. A serial robot manipulator has been limitedly applied to light-load deburring work due to the poor stiffness of the manipulator. A double parallel robot manipulator has been developed for a strong rigidity by stacking two parallel mechanisms. It can be applied to heavy-load deburring work with high stiffness. To apply the robot to cut the burrs on a unknown geometric surface, this research will develop an intelligent controller to measure bur track and cut it with a constant cutting force.

      • 서중조건하에서의 콘크리트 충전 강관 기둥의 시공을 위한 실험적 연구

        이장환,강용학,정근호,김진호,최문식,정상진 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1(구조계)

        The basic Physical properties, Slump, Slump flow, Air content, Bleeding, and Settlement of concrete was investigated to test Characteristic of Setting and to evaluate the relation between Model specimen and Heat of hydration for construction Over the High Temperature(CFT). The objective of this study is to take the partial core after the cementation of Model specimen, test the compression intensity and analyze the relation to Test piece.

      • KCI등재
      • 한국북방경역의 역사지리학적 연구(Ⅰ)

        이성학 慶北大學校 1969 論文集 Vol.13 No.-

        1) A study of historical change on the north frontiers of Korea. 2) The north boundary was the region of Yo-Dong (遼東) or the river of Pea (浿水) during Ancient-Korea dynasty. It was changed by the vicissitudes or rise and fall of the northern nations. 3) The Emperor of Han (漢) governed the peninsula of Han (韓). Its southern frontier was chiefly the northern region of the Han River (漢江) and the mountaion of Chul-Yung (鐵嶺) 4) Kokuryo(高句麗) occupied the greatest northern territory at the time of King, Yung Rak(永樂): the northern boundary was the eastern region of the river of Yo (遼河) and the region of the Song-Wha River was the large territory which were from Jang-Chun (長春) Nong-An(農安) Ha-L-Bin(哈爾濱) to the East-Sea. (東海) 5) Shilla(新羅) unified three states, yet the did not occupied all of Kokuryo territory but a part of it. The north-western frontier of Shilla was region on the river of Tea-Dong (大同江) Chung-Wha(中和) Sang-Won(祥原) and Kok-San(谷山). The north-eastern frontier of Shilla was the northern region of Chul-Yung(鐵嶺) An-byun(安邊) and northern Kang-Won(江原) of today. Shilla should have occupied the larger northern region, but it was not so large. Note : This is the northern frontier from Ancient-Korea to Shilla Dynasty, but those of Koryo(高麗) and Rhee Dynasty(李朝) will be mentioned at the next number.

      • KCI등재

        수목추출물의 생리활성에 관한 연구(XI) : 주목(Taxus cuspidata) 심재 추출성분 및 항산화활성 Compounds from Heartwood of Taxus cuspidata and Their Antioxdative Activities

        이학주,이성숙,최돈하,권영한 한국목재공학회 2003 목재공학 Vol.31 No.1

        항산화활성이 우수한 주목 심재 에탄올 추출물로부터 Sephadex LH-20, centrifugal partition chromatography (CPC), silica gel column chromatography 등을 이용하여 5종의 화합물을 단리하였으며, NMR, Mass spectrometry 등의 기기분석 결과 taxane 화합물인 taxusin를 비롯하여 lignan인 isolariciresinol (4, 4', 9.9' - tetrahydroxy-3', 5-dimethoxy-2, 7'-cyclolignan), lariciresinol (4, 4', 9-trihydroxy-3, 3'-dimethoxy-7, 9'-epoxylignan), taxiresinol (3, 4, 4', 9-tetrahydroxy-3'-methoxy-7, 9'-epoxylignan) 및 isotaxiresinol (3', 4, 4', 9, 9'-pentahydroxy-5-methoxy-2, 7'-cyclolignan)을 각각 동정하였다. 이들 단리된 화합물의 프리라디칼 소거능을 측정하여 항산화활성을 검정한 결과 taxusin을 제외한 3종의 lignan 화합물인 isolariciresinol, lariciresinol, isotaxiresinol 모두 천연항산화제 및 합성항산화제보다 높은 라디칼 소거능을 나타내어 항산화활성이 우수한 것으로 판명되었다. 이상의 결과 주목의 심재 에탄올 조추출물의 높은 항산화활성은 이들 성분에 기인하는 것으로 사료되었다. Antimicrobial and antioxidative activities of heartwood extractives of domestic species were investigated to develop a natural fungicide or preservative. Four lignan derivatives and one taxane were isolated from heartwood of Taxus cuspidata which has been selected due to its high antioxidative activity among the tested species. The chemical structures were identified as : taxusin, isolariciresinol (4,4',9,9'-tetrahydroxy-3',5-dimethoxy-2,7'-cyclolignan), lariciresinol (4,4',9-trihydroxy-3,3'-dimethoxy-7,9'-epoxylignan), taxiresinol(3,4,4',9-tetrahydroxy-3'-methoxy-79'-epoxylignan) and isotaxiresinol (3',4,4',9,9'-pentahydroxy-5-methoxy-2,7'-cyclolignan) on the basic of spectroscopic data and their chemical correlations. According to the results of free radical scavenging activity, isolariciresinol, lariciresinol and isotaxiresinol showed higher radical scavenging activity than those of α-tocopherol and butylated hydroxytoluene (BHT), the strongest natural and synthetic antioxidants. However, taxusin did not show any free radical scavenging activity. In this regard, it could inferred that high antioxidative activity of extractives of T. cuspidata was derived from isolariciresinol, lariciresinol and isotaxiresinol.

      • 난소절제후 Estrogen을 투여한 흰쥐 대동맥에서 Protein Kinase C-α와 Fas 발현의 변화

        이왕수,이상엽,안지현,송영빈,김학진,이광재,유재격,김상욱,김태호,김치정,류왕성 중앙대학교 의과대학 의과학연구소 2001 中央醫大誌 Vol.26 No.3

        Estrogen is believed to decrease coronary artery disease. Protein kinase C-α(PKCα)appear to be important in signal conduction pathways. Estrogen treatment increases catalytic activity of PKCα,and activation of PKCαcan modulate estrogen receptor levels and responsiveness. And it was reported that activation of PKC can protect cells from apoptosis induced by Fas ligation. But the beneficial effect of estrogen on PKCαwas not clearly demonstrated. The objective of this study was to evaluate the role of PKCαafter ovariectomy and estrogen therapy in rat aorta. The results were summarized as below: 1. The significant pathological changes were not observed in the rat aorta irrelevant to ovariectomy and estrogen therapy. 2. The expression of Fas was decreased in the aorta of estrogen-treated rats than that of ovariectomized rats without estrogen therapy. 3. Increased expression of PKCαwas more marked in the aprta of estrogen-treated rats than that of ovariectomized rat without estrogen therapy. In conclusion,PKCαmay be important in signal conduation pathway on the effect of estrogen. Activation of PKCαby estrogen reduced Fas expression, suggesting that PKCαactivation may play a role in protection against atherasclerosis. Further studies are needed to elucidate the role of PKCαafter estrogen therapy.

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼