• 제목/요약/키워드: Constituents

검색결과 3,562건 처리시간 0.023초

GPS 정밀단독측위기법을 이용한 해양조석하중 분조성분 검출 (Detection of Ocean Tide Loading Constituents Based on Precise Point Positioning by GPS)

  • 원지혜;박관동
    • Journal of Astronomy and Space Sciences
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    • 제26권4호
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    • pp.511-520
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    • 2009
  • 이 연구에서는 GPS(Global Positioning System) 정밀단독측위 기법을 이용하여 해양조석하 중(Ocean Tide Loading, OTL) 분조성분을 검출하고, 그 결과를 조석모델에 의한 예측값과 비교하였다. 고정밀 GPS 자료처리 프로그램인 GIPSY를 사용하여 인천, 서산, 제주 GPS 상시관측소를 대상으로 10분 단위의 수직좌표 시계열을 산출하였으며, 시계열의 조석조화분해를 통해 OTL 지각변위를 일으키는 주요 4대 분조($M_2$, $S_2$, $K_1$, $O_1$)의 진폭과 위상을 검출하였다. 조석모델의 예측값을 기준으로 GPS로 산출한 OTL 분조의 정확도를 평가한 결과 진폭은 제주관측소, 위상은 인천관측소에서 가장 높은 정확도를 나타내었다. 주요 11개 분조 중 최대비율을 차지하는 $M_2$분조의 경우 진폭성분에서 평균 23.8%의 상대오차를 보였다.

Modified Micellar Electrokinetic Capillary Chromatography에 의한 폭약 성분의 분리능 향상 (Improved Separation of Organic Explosives by Modified Micellar Electrokinetic Capillary Chromatography)

  • 박성우;양영근;홍성욱;김택제
    • 분석과학
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    • 제10권5호
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    • pp.325-331
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    • 1997
  • 계면활성제로 sodium dodecylsulfate(SDS)를 이용한 micellar electrokinetic capillary chromatography (MECC) 방법을 이용하여 유기 폭약 성분을 신속하고 정확하게 분석할 수 있는 방법을 연구하였다. 완충요액으로는 2.5mM borate와 25mM SDS(pH 8.5)를 사용하였고, 완충용액에 1M urea와 10% 유기 용매(acetonitrile, methanol 및 ethanol)를 첨가한 결과 분리능이 향상되는 현상을 관찰할 수 있다. 15종의 폭약 혹은 그 구성 성분을 MECC 방법으로 분리한 결과 RDX/TNB 및 DNN/DEP를 제외한 성분을 분리할 수 있었고, 검출한계는 1~4ppm으로 나타났다.

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Simultaneous Quantitation of Nine Constituents of Fraxinus rhynchophylla using High Performance Liquid Chromatography - Diode Array Detector

  • Ahn, Jong Hoon;Hwang, Bang Yeon;Lee, Mi Kyeong
    • Natural Product Sciences
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    • 제19권3호
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    • pp.236-241
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    • 2013
  • A high-performance liquid chromatography-diode array detector (HPLC-DAD) method was established for quantitative evaluation of nine constituents of Fraxinus rhynchophylla such as four coumarins, esculin (1), fraxin (2), esculetin (3), fraxetin (4), three lignans, syringaresinol 4,4'-O-${\beta}$-diglucoside (5), pinoresinol 4-O-${\beta}$-glucoside (6), pinoresinol (9), one secoiridoid, oleuropein (7), and one coumarinolignan, cleomiscosin C (8). The preferred chromatographic condition was obtained on Phenomenex Gemini-NX (3 ${\mu}m$, C18 110A, $150{\times}4.60$ mm) and the mobile phase was composed of water and acetonitrile using a gradient elution. The wavelength was set at 220 nm. Extraction condition of these constituents in F. rhynchophylla was also optimized through extraction time, extraction solvent and extraction method using established method. From this study, extraction at $70^{\circ}C$ with the mixture of ethanol and water for more than 12 h was suggested to be good extraction condition for these constituents. Quantitation of nine constituents in different F. rhynchophylla samples was also successfully accomplished with the newly established method.

연도별 버어리종 가공엽의 화학성분 함량 및 편차 (Chemical Constituents Contents and Deviations of Threshed Burley Tobacco Followed by Crop Year)

  • 김상범;복진영;안대진;이종률
    • 한국연초학회지
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    • 제25권2호
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    • pp.95-102
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    • 2003
  • To get the informations of quality uniformity of threshed burley tobacco produced from 1997 to 2001 and processed at various leaf processing factories, chemical constituents contents and coefficient of variation(C.V.) were analysed. The average chemical constituents contents of 12 grades during 5 years ranged as follows; nicotine 1.76~2.66%, total nitrogen 4.15~4.80%, crude ash 21.6~22.4% and chlorine 1.08~1.20%. The variations of chemical constituents contents among crop years was higher in nicotine while lower in crude ash. The nicotine content of upper leaves were influenced negatively by rainfalls, while total nitrogen content were influenced positively by air temperature and sunshine hours during July. The C.V. of chemical content in same grade was higher in chlorine and nicotine while lower in crude ash. The ratio of C.V. among leaf tobacco processing factories/C.V. of total sample in same grade was high in nicotine. To reduce the C.V. of chemical constituents, it is recommendable to thresh the leaf tobacco at one processing factory. When the leaves being processed at one factory, the decreasing effect of deviation was higher in nicotine, particularly.

극 저탄소강의 Intercritical coarse grained HAZ에서의 M-A상과 인장특성 간의 상관관계 (Correlation Between M-A Constituents and Tensile Properties in the Intercritical Coarse Grained HAZ of an Ultra Low Carbon Steel)

  • 이윤기;문준오;김상훈;이창희
    • Journal of Welding and Joining
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    • 제28권3호
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    • pp.99-103
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    • 2010
  • It is well known that martensite-austenite (M-A) constituents are formed in the intercritically reheated coarse grained heat affected zone (ICCGHAZ) of a multipass weld and they act on the local brittle zone (LBZ) in the welded structures. To investigate the effect of M-A constituents on the tensile properties of ICCGHAZ, specimens with M-A constituents of different volume fraction and size were prepared through the multipass welding cycles simulated by a Gleeble simulator and then tensile test was carried out. The results indicated that finely distributed M-A constituents contributed to decrease the yield ratio, which is mainly due to the increased tensile strength.

Differential Modulation of Volatile Constituents in Artemisia princeps and Artemisia argyi Plants after Gamma Ray or Electron Beam Irradiation

  • Kim, Ji Hong;Cho, Eun Ju;Lee, Min Hee;Kim, Ji Eun;Chung, Byung Yeoup;Kim, Tae Hoon;Kim, Jin-Hong
    • 방사선산업학회지
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    • 제6권1호
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    • pp.17-21
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    • 2012
  • The effects of gamma ray or electron beam irradiation on herbaceous medicinal plants were investigated in terms of the composition of volatile constituents using the aerial parts or leaves of Artemisia princeps Pamp. cv. Ganghwayakssuk and Artemisia argyi cvs. Namhaeyakssuk and Hwanghaessuk. The composition of volatile constituents in leaves was clearly distinguishable among the three Artemisia cultivars. However, the relative proportions of the major volatile constituents such as 1,8-cineole, ${\alpha}$-pinene, camphene, santolina triene, and artemesia triene, were similarly changed in two or three cultivars by gamma ray or electron beam irradiation. In particular, the proportion of 1,8-cineole was increased up to 1.29- to 1.71-fold in the three cultivars after irradiation with gamma ray. These results suggest that gamma ray or electron beam irradiation can be applied to modulate the composition of volatile constituents in the leaves of Artemisia plants.

Qualitative study on the key elements of obesity counseling in Korean Medicine

  • Sungha Kim;Seung Eun Chung;Kyungsun Han;Sunmi Choi;Jun-Hwan Lee
    • 대한한의학회지
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    • 제44권4호
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    • pp.1-13
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    • 2023
  • Objectives: Weight counseling is an inevitable process for patients with obesity who intend to lose weight; however, the contents of real-world counseling practices remain uncertain in Korean medicine (KM) practice. This study aimed to explore the structure and constituents of obesity counseling in KM. Methods: Qualitative methods were used to explore the structure of weight counseling and clinicians' approaches to weight counseling, particularly the advice and main constituents of weight counseling in KM. Nine KM clinicians (4 women, 5 men) from nine clinics completed face-to-face, individual and semi-structured interviews from September 2019 to February 2020 in Seoul, Daejeon, Cheonan, Seongnam, Asan, and Hwaseoug. The interviews were digitally recorded, transcribed verbatim, and categorized based on their constituents. Results: During weight loss counseling, the six principal constituents of KM identified were: planning with patients, motivation, correcting misinformation on weight loss, dietary and exercise advice, medication guidance, and customized guides for each type. Conclusion: Clinicians with in-depth knowledge about obesity prescribed personalized guidance for exercise, diet, and medication through an integrative approach. The study results provide an in-depth understanding of weight counseling in KM. These six constituents could guide the counseling provided by clinicians in obesity care.

Chemical Constituents and Pharmacological Activities of Hedyotis diffusa

  • Xu, Bao-Jun;Sung, Chang-Keun
    • Natural Product Sciences
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    • 제11권1호
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    • pp.1-9
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    • 2005
  • The chemical constituents from Hedyotis diffusa Willd and their pharmacological activities were summarized. It has been known data that this herb contains anthraquinones, terpenoids, steroids, flavonoids, organic acid, and polysaccharides. The studies of pharmacology have shown that Hedyotis diffusa Willd possess various levels of activities such as anticancer, anti-inflammatory, immunostimulatory, antioxidative, neuroprotective, and hepatoprotective activities.

신제품의 품질차원 활용에 관한 연구 (A Strategic Use of the Dimensions of Quality in New Product Development)

  • 강준모;박영택
    • 품질경영학회지
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    • 제27권4호
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    • pp.42-66
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    • 1999
  • We proposed eight dimensions and their constituents of product advantage in the last issue. In this study, using the dimensions and constituents, gap analyses are conducted on some product categories(; desktop computer, PCS terminal, and washing machine) in order to know what dimensions or constituents are major areas to be improved. For the purpose of strategic use of the dimensions of product advantage, Kano analyses are also applied. Based on the results of the gap analyses and Kano analyses, the future directions of new products development for the selected products are suggested.

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좁은산사나무엽의 약효성분 (I) (Pharmaco-Constituents of Crataegus pinnatifida var. psilosa Leaves(I) - The Constituents from Ether Fraction -)

  • 오인세;김일혁
    • 약학회지
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    • 제37권5호
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    • pp.476-482
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    • 1993
  • For the investigation of medicinal resources in Crataegus species, the present study was carried out to evaluate the pharmaco-constituents in the leaves of Crataegus Pinnatifida var. psilosa (Rosaceae). Fruits has folk medicine in Korea. From the $Et_{2}$O fraction of MeOH extract, a new compound, apigenin-8-C-(6"-acetyl)-$\beta$-D-glucopyranoside, named psilosin and three known compounds, ursolic acid, phytosterol complex and (-)-epicatechin were isolated and identified on the basis of their physico-chemical properties and spectroscopic evidences (UN, IR, NMR and mass etc.) in comparison with authentics, respectively.

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