• 제목/요약/키워드: O/D

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골담초엽의 플라보노이드 (The Flavonoids from Caragana Chamlagu Leaves)

  • 마충운;함인혜;황완균
    • 약학회지
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    • 제43권2호
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    • pp.143-149
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    • 1999
  • The phytochemical studies of the leaves of Caragana chamlagu were carried out as a sieries of the investigation of medicinal resources. The roots of Caragana chamlagu have been used as neuralgia, arthritis and migraine in the folk medicines of Korea. The methanolic extract of the leaves of Caragana chamlagu was suspended with water and then separated with chloroform. Compound I was isolated from precipitates of these water fraction by recrystalization. The aqueous fraction of MeOH extract was performed to column chromatography on Amberlite XAD-4 and Sephadex LH-20, and three compounds, compound II, compound III, and compound IV were isolated. The structures of the four compounds were elucidated by spectroscopic data of $^1H-NMR$, ^{13}C-NMR$, IR, and FAB-MS. Compound I-IV were tilianine ($acacetin-7-O-{\beta}-D-glycopyranoside$), rutin($quercetin-3-O-{\alpha}-L-rhamnopyranosy(1{\rightarrow}6)-{\beta}-D-glu-copyranoside$), $kaempferol-3-O-{\alpha}-L-rhamnopyranosyl(1{\rightarrow}6)-{\beta}-D-galactopyranoside$, and apigetrin, ($apigenin-7-O-{\beta}-D-glycopyranoside$), respectively.

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윤노리나무 과실의 페놀성 성분 (Phenolic Components from the Fruits of Pourthiaea villosa)

  • 이현진;안달래;이은별;이태관;김대근
    • 생약학회지
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    • 제44권1호
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    • pp.16-21
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    • 2013
  • The fruits of Pourthiaea villosa were extracted with methanol and its extract was fractionated with n-hexane, methylene chloride, ethyl acetate and n-butanol. Repeated column chromatography of silica gel, sephadex LH-20 and HPLC led to the isolation of nine phenolic compounds from ethyl acetate soluble fraction. The chemical structures were elucidated as kaemferol-3-O-${\beta}$-D-glucopyranoside (astragalin) (1), isorhamnetin-3-O-${\beta}$-D-glucopyranoside (2), kaempferol-3-O-${\beta}$-D-xylopyranosyl($1{\rightarrow}2$)-${\alpha}$-L-rhamnopyranoside (3), caffeic acid (4), quercetin-3-O-${\beta}$-D-xylopyranosyl($1{\rightarrow}2$)-a-L-rhamnopyranoside (5), quercetin-3-O-${\beta}$-D-xylopyranosyl($1{\rightarrow}2$)-${\beta}$-D-glucopyranoside (6), quercetin-3-O-${\beta}$-D-xylopyranosyl($1{\rightarrow}2$)-${\beta}$-D-galactopyranoside (7), quercetin-3-O-${\alpha}$-L-rhamnopyranoside (quercitrin) (8), and kaempferol-3-O-${\alpha}$-L-rhamnopyranoside (afzelin) (9) by spectroscopic techniques. These compounds were isolated from this plant for the first time.

A Computer Code DEUKER for $D_2$O Scattering cross Section

  • Shu, Soo-Hyun;Kim, Seong-Yun;Kim, Dong-Hoon
    • Nuclear Engineering and Technology
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    • 제10권3호
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    • pp.145-151
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    • 1978
  • D$_2$O에 대한 Butler의 scattering kernel에 관해 조사하였다. 이 kernel을 사용한 전자계산 코드 DEUKER를 개발하였으며 이를 이용하여 산란법칙, 미분산란 단면적 및 전산란 단면적을 계산하였다. D$_2$O 분자내의 어떤 두개 원자간의 산란 영향은 열에너지 영역에서의 산란 중성자 분포를 결정하는데 있어서 중요한 인자가 된다. 따라서 여러 입사 중성자 에너지에 따른 에너지 전달 산란 단면적에 관해 조사하여 이 kernel의 원자로 내의 중성자 분포 계산을 위한 사용 가능성을 연구하였다. 또한 본 연구를 통하여 D$_2$O와 $H_2O$에서의 중성자 산란 과장의 차이점을 밝혔다.

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바인더젯 3D 프린팅을 위한 TiO2 입자를 함유한 시멘트 기반 재료의 기계적 성능 및 광촉매 특성 분석 (Characterization of mechanical and photocatalytic performance on cement-based materials with TiO2 particles for binder jet 3D printing)

  • 유준성;리패기;배성철
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2023년도 가을학술발표대회논문집
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    • pp.69-70
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    • 2023
  • The development of advanced 3D printing technologies has opened up new opportunities for customized digital designs in the construction industry. Using nano- and micro-scale additives is expected to improve the performance of cement-based materials in 3D printing. TiO2 particles have been widely used as reinforcing additives in cement-based materials. Therefore, this study aims to investigate the application of cement-based materials containing multi-size TiO2 particles in binder jet 3D printing and the effect of different-size TiO2 particles on the performance of printed samples. TiO2 particles exhibit an excellent filling effect, which increases the density of the printed samples and promotes hydration, thereby improving the compressive strength of the samples. In addition, larger TiO2 particles exert more pronounced filling and photocatalytic effects on the resulting samples.

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TiO2 입자의 사이즈가 바인더젯 3D 프린팅 시멘트계 재료의 특성에 미치는 영향 (Effect of nano-TiO2 size on the properties of cement-based materials produced by binder jet 3D printing)

  • 유준성;리패기;배성철
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2022년도 봄 학술논문 발표대회
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    • pp.188-189
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    • 2022
  • With the development of nano-reinforcement technology, TiO2 nanomaterials have received widespread attention as one of the additives without pozzolanic reaction, which can be used to improve the mechanical properties of cement-based materials. Meanwhile, with the development of additive manufacturing technology or known as 3D printing technology, its application in the construction field has also got noticed. Therefore, in this work, the effect of three sizes of TiO2 on the compressive strength of hardened cement-based materials fabricated by binder jetting 3d printing was evaluated. According to the results, the TiO2 particles with larger sizes can provide better reinforcement to the hardened cement due to its more significant filling effect.

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Isolation and Identification of Anthocyanins from Purple Sweet Potatoes

  • Lee, Lan-Sook;Chang, Eun-Ju;Rhim, Jong-Whan;Ko, Byoung-Seob;Park, Sang-Won
    • Preventive Nutrition and Food Science
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    • 제2권2호
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    • pp.83-88
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    • 1997
  • Anthocyanin pigments of purple sweet potato roots (Ipomoea batatas L.) were extracted with 0.5% TFA (Trifluoroacetic acid) in 95% EtOh, and further isolated an purified by Amberlite XAD-7 and ODS column chromatography, and final preparative HPLC. Among nine anthocyanins isolated, the structure of three major anthocyanins were identified as 3-O-(6-O-trans-caffeyl)-2-O-(6-O-trans-caffeylglucopyranosyl)-$\beta$-D-glucopyranosyl-5-O-($\beta$-D-glucopyranosyl)-peonidin, 3-O-(6-O-trans-caffeyl)-2-O-(6-O-trans-feruloyl-glucopyranosyl)-$\beta$-D-glucopyranosyl-5-O-($\beta$-D-glucopyranosyl)-peonidin, and 3-O-(6-O-trans-caffeyl)-2-O-(6-O-p-hydroxylbenzoylglucopyranosyl)-$\beta$-D-glucopyranosyl)-peonidin, by using UV-visible absorption spectra, $^1$H-NMR and FAB-MS analysis.

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예산제약하에서 O/D 추정을 위한 최소표본율 결정 (Sample Size Determination for O/D Estimation under Budget Constraint)

  • 신희철;이향숙
    • 대한교통학회지
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    • 제24권3호
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    • pp.7-15
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    • 2006
  • O/D 추정을 위한 표본조사시 최소표본율의 결정은 조사 전체 및 구축된 O/D의 신뢰성과 직결되는 중요한 문제이다. 현재 대부분의 O/D 추정을 위한 교통조사시 정해진 기준 없이 단순히 전체 모집단에 대하여 정률로 표본율을 결정하거나, 모집단의 크기에 따라 약간씩 표본수를 가감하는 표본율을 사용하고 있으나, 적용시 신뢰성 문제가 존재하므로 이에 대한 보완이 필요하다. 본 연구에서는 이러한 문제점의 해결방안으로 최악의 경우에도 zero cell을 없애도록 고안된 교통조사지침의 표본수결정식을 이용하되, 이 방법의 문제점인 과도한 표본율을 줄이기 위하여 카테고리수를 조사여건에 따라 차등 적용하여 예산제약의 문제를 해결하는 방안에 대하여 검토하였다. 전국 지역간 여객 O/D자료를 대상으로 기존 O/D자료에서 zero cell을 제외하는 경우(1안), 대권역으로 적용하는 경우(2안) 인접죤으로 통행하는 경우(3안), 다음 인접죤까지 통행하는 경우(4안) 등 4개 안을 제안하여 분석하였고. 그 결과 각 대안들은 신뢰성과 표본율 측면에서 대체관계(trade-off)로 각각 장단점을 내포하고 있는 것으로 나타났으므로, 각 조사기관은 조사의 신뢰성과 예산 등의 문제를 포괄적으로 고려하여 최적의 방법을 선택하여 적용하여야 할 것이다.

재배 조건에 따른 바위솔의 Flavonol Glycoside 함량 변화 (Changes in Flavonol Glycoside Contents of Orostachys Japonicus a. Berger according to Cultivation Conditions)

  • 장상훈;강동민;강진호;박종철;이상경;신성철
    • 한국약용작물학회지
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    • 제13권6호
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    • pp.250-254
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    • 2005
  • Night-break, 일장조절, 월동가온 실험으로부터 얻어진 바위솔에 포함된 flavonol glycoside, $kaempferol-3-O-{\beta}-D-glucoside$(1), $kaempferol-3-O-{\beta}-D-glactoside$ (2), $kaempferol-3-O-{\beta}-D-rhamnoside$ (3), $quercetin-3-O-{\beta}-D-glucoside$ (4) and $quercetin-3-O-{\alpha}-D-rhamnoside$ (5)의 함량이 분석되었으며 자연산 바위솔의 함량과 비교되었다. 월동가온 시험에서 얻은 flavonol glycoside 1-5의 함량은 자연산보다 감소하였으며 일장조절 실험 및 night-break 시험에서 얻은 flavonol glycoside 함량은 조사한 빛의 양이 증가함에 따라 증가하였다. 월동가온은 flavonol glycoside의 생성에 부정적으로 작용하는 반면 조사되는 빛의 양의 증가와 같은 경작조건은 flayonol glycoside의 생성에 유리하다.

한.양방 협진체계 개발에 관한 연구 (A Study on Cooperative Medical Treatment System between Oriental and Western Medical Practitioners)

  • 이동희;류규수
    • 한국병원경영학회지
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    • 제3권1호
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    • pp.34-61
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    • 1998
  • A study on cooperative medical treatment system between oriental and western medical practitioners was conducted from March through August 1997 in order to determine a productive model of cooperation of two medical parts for treatment of patients. Questionnaires were distributed to 195 medical doctors(M.D.) and 195 doctors of oriental medicine(O.M.D.) working in clinics and hospitals in six major cities. Statistical analysis tools used for this study were frequency, t-test and multiple regression by using SPSS/P.C package. The results are summarized as follows: 1. The respondents were composed of male docotors(78%) and female doctors(22%) and 68.2% of M.D. and 97% of O.M.D. were interested in the other medical part. The doctors of both disciplines had some limitation on treatment of patients but they were reluctant to refer their patients to other doctors in different discipline. 2. M.D assumed that oriental medicine was more effective for chronic diseases, and O.M.D. thought that western medicine was more effective for acute diseases. 92.3% of O.M.D.s responded that even though they do not utilize western medical technology for diagnosis, they believed the results of diagnoses by western medical technology. 3. 60.5% of O.M. and 93.3% of O.M.D. said that cooperative medical treatment system could be necessary for patients and it would be effective for control of diseases and 69% of western medical doctors and 99% of oriental medical doctors agreed that oriental medical practice would be more effective for cerebellar vascular accidents than other diseases. 77.4% of western medical doctors and 92.3% of oriental medical doctors responded that the students of two different disciplines have to be taught on the other disciplines. 82.6% of western medical doctors and 83.3% oriental medical doctors agreed that it would be necessary to have collaborative research between scientists in two disciplines. 81.5% of M.D.s and 93.3% of O.M.D.s believed that they had prejudice and distrust on other discipline 4.90% of the doctors were not satisfied with the government medical policies on health insurance, legal matters, and health delivery system. 5. 75.4% of M.D.s and 50.2% of O.M.D.s said that two medical disciplines should be integrated, but they were skeptical on that. 75.3% of M.D.s thought that western hospitals should employ O.M.D.s Finally this study recommended that western medical students study oriental medicine and the vice versa, and M.D.s and O.M.D.s should have seminars and workshops to exchange knowledge, and experiences. It is also recommended that medical laws be revised to allow medical doctors refer the patients whom they can not handle to oriental medical doctors and the vice versa.

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$Bi_2Sr_2CaCu_2O_{8+\delta}$ 고온초전도체의 d-파 대칭성 증거로서의 $Pb/Bi_2Sr_2CaCu_2O_{8+\delta}$접합 투과전도특성 (Tunneling Characteristics in $Pb/Bi_2Sr_2CaCu_2O_{8+\delta}$ Junctions as an Evidence for a d-wave Order Parameter Symmetry in $Bi_2Sr_2CaCu_2O_{8+\delta}$ Superconductors)

  • Chang, Hyun-Sik;Lee, Hu-Jong
    • Progress in Superconductivity
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    • 제2권2호
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    • pp.65-70
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    • 2001
  • $Pb/Bi_2Sr_2CaCu_2O_{8+\delta}$-single-crystal junctions with the tunneling direction along the c axis of the crystal were fabricated to obtain an s-wave-superconductor/d-wave-superconductor Josephson junctions. The tunneling R (T) curves and current-voltage characteristics show distinct features which can be explained only under the assumption that the order parameter of high-$T_c/Bi_2Sr_2CaCu_2O_{8+{\delta}}$ superconductors has a pure d-wave symmetry, which is in contrast to the case of $YBa_2Cu_3O_{7+{\delta$}}$erconductors where a minor s-wave component is also present..

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