• Title/Summary/Keyword: II-VI

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Redescription of Haloptilus caribbeanensis (Copepoda: Calanoida) from the Pacific, with Remarks on the Morphology of Antennules in the Genus Haloptilus

  • Soh Ho Young;Suh Hae-Lip;Ohtsuka Susumu
    • Fisheries and Aquatic Sciences
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    • v.2 no.2
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    • pp.129-134
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    • 1999
  • Haloptilus caribbeanensis Park, 1970 (Copepoda, Calanoida, Augaptilidae) is redescribed in detail on the basis of an adult female collected from Suruga Bay, Japan. This is the first record of the species from the Indo-Pacific region. Morphology of the Pacific specimen agrees well with that of the Caribbean Sea and Gulf of Mexico specimens, except for the numbers of mandibular teeth. The former has five teeth and the latter six teeth on mandible. The segmentation and segmental aesthetasc numbers of female antennules of H. caribbeanensis are compared with those of five species of Haloptilus (H. angusticeps, H. fons, H. longicomis, H. ornatus and H. spiniceps). These characters show morphological differentiation at the species level. H. caribbeanensis has no aesthetasc on the proximal segments II, IV, and VI of the female antennules.

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Analysis on the forest Community Structure of Daewon Valley in Chirisan national Park (지리산국립공원 대원사계곡의 삼림군집구조 분석)

  • 권전오
    • Korean Journal of Environment and Ecology
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    • v.13 no.4
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    • pp.354-366
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    • 2000
  • 지리산국립공원 대원계곡의 삼림군집구조를 분석하여 국립공원관리의 기초자료를 제공하기 위하여 기조사지역(이경재 등, 1991)이외의 지역에 대해 39개 조사지(100m2)를 설정하고 식생조사를 실시하였다 Classification의 한 기법인 TWINSPAN을 사용하여 군집을 분리하였으며 그 결과 느릅나무-굴참나무군집(군집 I) 졸참나무-굴참나무군집(군집II) 졸참나무군집(군집III-V) 신갈나무군집(군집VI) 그리고 서어나무-노각나무군집(군집VII)의 7개 군집으로 나뉘었다 각 군집에 대해 우점도 종다양도 유사도 종수 및 개체수 그리고 흉고직경 등의 분석을 통해 군집의 종조서을 살펴본 결과 지리산 대원계곡의 삼림은 졸참나무 굴참나무 신갈나무 등의 참나무가 주류를 이루고 있었으며 점차 서어나무와 노각나무등으로 천이가 진행되어갈 것으로 판단되었다.

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Synthesis of certain 2-aminoadmantane derivatives as potential antimicrobial agents

  • Eisa, Hassan M.;Tantawy, Atif S.;El-Kerdawy, Mohamed-M.
    • Archives of Pharmacal Research
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    • v.13 no.1
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    • pp.74-77
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    • 1990
  • N-(2-Amamantyl)-N-(5-arylhydrazono-6-methyl-4-oxopyrimidin-2-yl) guanidines (IIIa, b), 2-(2-admantyl-amino)-4-amino-s-triazine (IVa) and its 6-chloromethyl derivative (IVb) were prepared by cylization of 1-(2-admantyl) biguanide HCl (I) with ethyl 2-arylhydrazono-3-oxobutyrates (II), ethyl formate and ethyl chloroacetate, respectively. Where 1-(2-admantyl)-3-(4, 5-dioxo-2-imidazolidinylidene)guanidine (V) was used as intermediate for the synthesis of amides (VIIa, b), hydrazide (VIII) and azomethine derivatives (IX, b) of alkyl 2-(2-admantyl-amino)-4-amino-2-triazine-6-carboxylates (VI a, b). The antimicrobial testing of the prepared compounds proved that compound 1Xb was the most active. It showed a marked bacteriostatic effect against Staphylococcus aureus and Bacillus subtilis.

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MATRIX ELEMENTS AND CROSS SECTION OF RAMAN SCATTERING BY ATOMIC HYDROGEN

  • Lee, Hee-Won
    • Publications of The Korean Astronomical Society
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    • v.22 no.1
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    • pp.21-33
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    • 2007
  • Ever since the identification of 6830 and 7088 features as the Raman scattered O VI 1032, 1038 resonance doublets in symbiotic stars by Schmid (1989), Raman scattering by atomic hydrogen has been a very unique tool to investigate the mass transfer processes in symbiotic stars. Discovery of Raman scattered He II in young planetary nebulae (NGC 7027, NGC 6302, IC 5117) allow one to expect that Raman scattering can be an extremely useful tool to look into the mass loss processes in these objects. Because hydrogen is a single electron atom, their wavefunctions are known in closed form, so that exact calculations of cross sections are feasible. In this paper, I review some basic properties of Raman scattered features and present detailed and explicit matrix elements for computation of the scattering cross section of radiation with atomic hydrogen. Some astrophysical objects for which Raman scattering may be observationally pertinent are briefly mentioned.

위상그래프와 회로망해석이론 I

  • 장세훈
    • 전기의세계
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    • v.28 no.3
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    • pp.27-34
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    • 1979
  • 회로망을 해석하는데는 i) 지로해석법, ii) 루우프해석법, iii) 메슈해석법, iv) 마디해석법, v) 컷세트해석법및 vi) 상태공간해석법 등이 사용됨은 이미 알고 있다. 다루는 회로가 비교적 간단한 구성의 선형, 시불변 회로망이고 또한 종이와 연필로 회로망해석을 수행하여야 될때에는 익혀온 이들 해석법을 관례대로 따르면 될 것이나, 다룰려는 회로망이 대형인 복잡한 구조의 것이든지 혹은 비선형소자, 시변소자 등을 포함하는 경우에는 독립회로방정식들을 체계있게 세워 나가는데에도 어려움이 있거니와, 설혹 회로방정식군을 세웠다 하드라도 이들을 풀어 나가는데에도 이젠 우리가 할 수 있는 능력한계를 느끼게 된다. 전자계산기가 스스로 독립성을 지닌 필요한 개수의 회로망방정식들을 작성하고, 또한 풀이도 요구되는 특성을 갖는 회로망을 설계하여주면, 많은 수고와 번거로움이 덜어진다. 이러한 뜻에서 전산기의 활용에 의한 회로망의 해석, 설계 (computer oriented network analysis and synthesis)이론이 바람직하다. 여기서는 이러한 전산기의 사용에 의한 회로망의 해석, 설계이론의 기초가 되는 부분을 가려서 위상 그래프이론에 따른 회로망 해석방법을 해설한다.

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ASTROPHYSICS OF DUSTY STELLAR WINDS FROM AGB STARS

  • Suh, Kyung-Won
    • Journal of The Korean Astronomical Society
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    • v.47 no.6
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    • pp.219-233
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    • 2014
  • The main site of dust formation is believed to be the cool envelopes around AGB stars. Nearly all AGB stars can be identified as long-period variables (LPVs) with large amplitude pulsation. Shock waves produce by the strong pulsation and radiation pressure on newly formed dust grains drive dusty stellar winds with high mass-loss rates. IR observations of AGB stars identify various dust species in different physical conditions. Radio observations of gas phase materials are helpful to understand the overall properties of the stellar winds. In this paper, we review (i) classification of AGB stars; (ii) IR two-color diagrams of AGB stars; (iii) pulsation of AGB stars; (iv) dust around AGB stars including dusty stellar winds; (v) dust envelopes around AGB stars; (vi) mass-loss and evolution of AGB stars; and (vii) contribution of AGB dust to galactic environments. We discuss various observational evidences and their theoretical interpretations.

Phytochemical Studies on Reynoutriae Radix $('H\check{u}-Zh\grave{a}ng')$

  • Chi, Hyung-Joon;Kim, Hyun-Soo
    • Korean Journal of Pharmacognosy
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    • v.17 no.1
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    • pp.73-77
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    • 1986
  • Anthraquinones, physcion (I), mp $204{\sim}205^{\circ}$ and emodin (II), mp $254{\sim}255^{\circ}$, and $emodin-8-O-{\beta}-{_D}-glucoside$ (IV), mp $191{\sim}192^{\circ}$ together with ${\beta}-sitosterol$ glucoside (III), mp $280{\sim}282^{\circ}$ were isolated from the roots of Polygonum ellipticum Migo and P. sachalinense Fr. Schm. (Polygonaccae). Stilbene derivatives, 3,5,4'-trihydroxystibene (V), mp $258{\sim}260^{\circ}$ and $3,5,4'-trihydroxystilbene-3-O-{\beta}-{_D}-glucoside$ (VI), mp $142{\sim}144^{\circ}$ were also isolated.

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Analysis on the Forest Community Structure of the Area of Donghaksa-Nammaetap. Kyeryongsan National Park (계룡산국립공원 동학사-납매탐구간의 삼림군집구조 분석)

  • 최송현;조현서
    • Korean Journal of Environment and Ecology
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    • v.14 no.4
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    • pp.252-267
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    • 2001
  • 계룡산국립공원 동학사-남매탑구간의 산림군집구조를 분석하기 위하여 64개 조사구를 설정하고 식생구조를 실시하였다. Classification의 기법 중 하나인 TWINSPAN을 이용하여 군집분리를 시도하였으며, 그 결과 소나무 군집(I), 굴참나무-소나무군집(II), 서어나무-굴참나무군집(III), 굴참나무-졸참나무군집(IV), 서어나무-까지박달군집(V), 신갈나무-서어나무군집(VI), 느티나무-졸참나무군집(VII) 그리고 느티나무군집(VIII)의 8개로 분리되었다. 연륜분석결과 이지역의 임령은 약 60년 안팍이었으며, 단위면적(100$\m^2$)당 평균출현종수는 15.0$\pm$3.2종. 평균출현개체수는 95.7$\pm$37.3주었다. 이상의 결과를 통해 계룡산국립공원이 동학사-남매탑구간 지역은 소나무림에서 굴참나무, 졸참나무, 신갈나무림을 거쳐 서어나무, 까지박달림으로 천이가 진행될것으로 예상되었다.

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Antitumor Activity of some Phenolic Components in Plants

  • Ryu, Shi-Yong;Choi, Sang-Un;Lee, Chong-Ock;Lee, Seung-Ho;Ahn, Jong-Woong;Zee, Ok-Pyo
    • Archives of Pharmacal Research
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    • v.17 no.1
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    • pp.42-44
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    • 1994
  • The activity-guided fractionation of some medicinal plants led to yield five kinds of natural stilbene compounds namely 3, 5-dihydroxy-4'-methoxystillbene(I), rhapontigenin(II), reveratrol(III), rhaponticin(IV) and piceid(V) and two common flavonoids, apigenin(VI) and luteolin(VII) as active principles of the antitumor property, in vitro, against five kinds of human tumor cell lines, A-549, SK-OV-3, SK-MEL-2, XF-498 and HCT15.

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Antitumor activity of Trichosanthes kirilowii

  • Ryu, Shi-Yong;Lee, Seung-Ho;Lee, Sang-Un;Lee, Chong-Ock;No, Zaesung;Ahn, Jong-Woong
    • Archives of Pharmacal Research
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    • v.17 no.5
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    • pp.348-353
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    • 1994
  • The activity fractionation upon the MeOH extract of the root of trichosanthes kirilowii led to the isolation of eight cucurbitane tritepense namely cucurbitacin .betha. (I), isocucurbitacin .betha.(II), cucurbitacin D(III), isocucurbitacin D(IV), 3-epi-isocucurbitacin .betha(V), dihydrocucurbitain .betha. (VI), dihydroisocucurgbitachin .betha. (VII) and dihydrocucurbitacin E (VIII), as active principles. All isolates were shown to exhibit significant cytotoxicity against cultured human tumor cells, including A-549, Sk-OV-3, Sk-MEL-2, XF-498 and HCT 15, with an exceptionally high potency.

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