• Title/Summary/Keyword: Tertiary

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Six New Agelas Species (Demospongiae: Agelasida: Agelasidae) from Kosrae Island, The Federated States of Micronesia

  • Sim, Chung Ja;Kim, Young A
    • Animal Systematics, Evolution and Diversity
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    • v.30 no.3
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    • pp.196-205
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    • 2014
  • This paper describes six new species of sponges in the genus Agelas from Kosrae Island, The Federated States of Micronesia. Most Agelasid sponges are known from only tropical regions. All the new Agelas species; A. fragum n. sp., A. kosrae n. sp., A. purpurea n. sp., A. bakusi n. sp., A. vansoesti n. sp. and A. incrustans n. sp. are compared with other valid species that were studied. Six new species differ from the other species by morphology, growth form, skeletal fibres, habitats and spicule size. Agelas fragum n. sp. is characterized by its tuberculate surface and primary fibres with brush-like spicules. Agelas kosrae n. sp. is differs in skeletal structure and have tertiary fibres. Agelas purpurea n. sp. is characterized by primary, secondary and tertiary fibres are all cored with spicules. Agelas bakusi n. sp. is similar to Agelas clathrodes in shape, but differs in the primary fibres. Agelas vansoesti n. sp. is characterized by having acanthostrongyles. Agelas incrustans n. sp. is distinguished by its encrusting and not cavernous interior.

Geologic Structure of Euiseong Sub-basin from Spectrally Correlated Geopotential Field Anomalies (포텐셜필드의 스텍트럼대비법을 이용한 의성소분지의 지구조 연구)

  • 김원균
    • Economic and Environmental Geology
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    • v.33 no.3
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    • pp.217-228
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    • 2000
  • We use spectral correlation method to analyze gravity and magnetic anomalies of Euiseong Sub-basin for distribution of rock facies and gelogic structures. The analysis reveals distinct polarity between gravity and magnetic anomaly correlation ; intermediate to mafic intrusives, extrusives, and the Tertiary basin shows positive gravity (+G) and positive magnetic (+M) correlation. Granitic gneiss and felsic volcanics negative gravity 9-G) and negative magnetic (-M) correlation. The Palgongsan granite, felsic to mafic extrusives and Mesozoic granites are characterized by -G and + M correlation. +G and -M correlations in the sedimentary formations are interpreted by uplift of pre-Cretaceous basement rocks . The + G and + M correlation characteristics in northeastern part of Euiseong Sub-basin including the Tertiary sedimentary basin result from the uplift of crustal materials. Major axes of spectrally correlated amomalies have mostly NW-SE or NE-SW directions. The former is due to the intrusives along strike-slip faults, and the latter which is observed in sedimentary formations is related to geological structures of basement associated new insight into the boundary between Euiseong and Milyang Sub-basin.

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Studies on the Distribution Coefficient of the Primary, Secondary, Tertiary Amine and Quaternary Ammonium-methylorange Salts

  • Kim, Bak-Kwang
    • YAKHAK HOEJI
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    • v.18 no.3
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    • pp.183-189
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    • 1974
  • Distribution coefficients between nitrobanzene solution and deionized water, show a straight line when the number of alkyl radicals against the logarithm of distribution coefficient of the salts was plotted. After extracting salts of the indicator and the cationic surfactants with organic solvents, and employing the colorimetric method was used. A calculation method of distribution coefficients of the salts in the organic solvent has been suggested and it could be used for the extraction equilibrium of the primary amine, $CH_{3}(CH_2)_{n}NH_3^+$ secondary amine, $CH_{3}(CH_2)_{n}NH_{2}(CH_3)^+$, tertiary amine $CH_{3}(CH_2)_{n}NH(CH_3)_2^+$ and quaternary ammonium, $CH_{3}(CH_2)_{n}N(CH_3)_3^+$MO$^-$salts, (n=3,5,7,11).

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Application of Two Centre Huckel Method for C-C Bond Fission and Hydrogen Abstraction of Saturated Hydrocarbons (二中心 Huckel 法의 應用. 포화탄화수소의 C-C 切斷 및 水素의 反應性)

  • Park, Byung-Kak;Lee, Mu-Sang
    • Journal of the Korean Chemical Society
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    • v.16 no.2
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    • pp.59-63
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    • 1972
  • In connection with two electron binding energy of each bond of saturated hydrocarbons, C-C bond fission and hydrogen abstraction from C-H bond are discussed by means of two center Huckel method. A beautiful correlation could be noticed between the observed bond dissociation energy and the calculated bond energy except for n-butane. Bond dissociation energies between C-C bond were also related to C-C bond fission. We could also find a very close relation between the relative easiness of hydrogen abstraction and the calculated binding energy of C-H bond. In other words, C-H bonds of tertiary hydrogen have been noticed as most weakely bonded and hence the tertiary hydrogen would most easily from the paraffins. In addition, the C-H binding energy is discussed applying ionic character of C-H bond which is derived from its dipole moment (0.4D)

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Analyses of Fossil Pollen of Tetiary Miocene in the Yeonil Area, Korea (연일지역 신생대 제삼기 마이오세층의 화석화분 분석에 관한 연구)

  • Chang, Nam-Kee;Ki-Wan Kim;Jae-Geun Kim
    • The Korean Journal of Ecology
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    • v.11 no.3
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    • pp.137-144
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    • 1988
  • The use of modern pollen spectra for comparative interpretation of fossil pollen sequence requires the ability to distinguish different vegetation types by their pollen spectra, which may show similarities to fossil assemblages. Tertiary marine and non-marine sediments, the Yeonil Group, of the Yeonil area, Korea, was found thirty-two palynomorphic genera. One of the characteristic features of Yeonil geo-flora is predominance of coniferous trees over shrubs, herbs, and ferns. Miocene deposits of Yeonl area, Korea, ae differentiated with five zones. According to the pollen diagram it can be inferred the climate of the Tertiary Miocene of the Yeonil area, Korea.

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An Efficient Clamp to Reduce Switch Voltage Stress of Forward Converter (포워드 컨버터의 스위치 전압 스트레스 감소를 위한 효율적 클램프)

  • Kim, Marn-Go
    • The Transactions of the Korean Institute of Power Electronics
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    • v.21 no.1
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    • pp.10-18
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    • 2016
  • In this study, an efficient clamp is proposed to reduce the switch voltage stress of a forward converter. The proposed clamp consists of a conventional LC snubber, a tertiary winding, and a diode. When the switch is turned OFF, the magnetizing inductor energy of the transformer is recovered directly into the flyback output, which is the tertiary winding and diode network, instead of circulating in the LC snubber. Therefore, switch voltage stress and circulating current caused by the magnetizing inductor energy are reduced. This condition improves the efficiency of the forward converter with limited switch voltage stress. A theoretical analysis and the design guidelines of the proposed converter are provided. Experimental results are also reported.

DETERMINATION OF TRIETHANOLAMINE BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY WITH POST COLUMN REACTION

  • Kim, Jin-Woo;Kim, Seung-Jung;Lee, Bo-Seaub
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.14 no.1
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    • pp.1-15
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    • 1988
  • A new method for liquid chromatography with post column reaction is suggested for the separation and quantification of tertiary amines. A mixture of triethanolamine and N-ethyl diethanolamine was separated by a strong cation exchange column, followed by spectrophtometric detection of the blue colors generated from the reaction of each amine with the Folin-Ciocalteau reagent. The tertiary amines were properly separated when an eluent of pH 9.5 containing 0.5M sodium nitrate was used. Under this condition, calibration curve of triethanolamine in 2-10mg/100ml concentration range was attained. Good results were obtained when cream and shampoo preparations containing known amount of triethanolamine were analysed according to this method. In case the sample did not contain any other interfering reducing substances, the amine was quantitatively determined by the simple reaction of the samples with Folin-Ciocalteau reagent, and the subsequent spectrophotometric measurement.

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Studies on Benzofuran-7-carboxamides as Poly(ADP-ribose) Polymerase-1 (PARP-1) Inhibitors

  • Lee, Sun-Kyung;Yi, Kyu-Yang;Lee, Byung-Ho;Oh, Kwang-Seok
    • Bulletin of the Korean Chemical Society
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    • v.33 no.4
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    • pp.1147-1153
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    • 2012
  • Benzofuran-7-carboxamide was identified as a novel scaffold of poly(ADP-ribose) polymerase-1 (PARP-1) inhibitor. A series of compounds with various 2-substituents including (tertiary amino)methyl moieties substituted with aryl ring and aryl groups containing tertiary amines, were synthesized and biologically evaluated to elucidate the structure-activity relationships and optimize the potency. 2-[4-(Pyrrolidin-1-ylmethyl)phenyl]-benzofuran-7-carboxamide (42) was the most potent as an IC50 value of 40 nM among those.

Protective Effect of Stilbenes on Oxidative Damage

  • Na, Min-Kyun;Min, Byung-Sun;Bae, Ki-Hwan
    • Natural Product Sciences
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    • v.13 no.4
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    • pp.369-372
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    • 2007
  • Oxidative stress induced by reactive oxygen species (ROS) has been suggested to be the cause of various degenerative diseases as well as aging. To evaluate the antioxidant potential of stilbenes, we have investigated the cytoprotective effect of 10 stilbenes derived from plants on the oxidative stress induced by tertiary butyl hydroperoxide (t-BuOOH). Of the stilbenes tested, piceatannol (3) showed the most potent activity, which was further investigated using an animal model. When 3 (30 or 10 mg/kg) was topically administered prior to UVB irradiation, the amount of the thiobarbituric acid reactive substances (TBARS) was significantly reduced compared to that of the control (vehicle). Our findings suggest that piceatannol is capable of protecting cells and tissues from oxidative stress.

NMR Study of Effects of $MgCl_2$ on the Structural and Dynamical Properties of Yeast Phenylalanyl tRNA

  • Se Won Suh;Byong Seok Choi;Ki Hang Choi;Jin Young Park
    • Bulletin of the Korean Chemical Society
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    • v.13 no.5
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    • pp.517-520
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    • 1992
  • Solvent exchange rates of selected protons were measured by NMR saturation recovery method for yeast $tRNA^{Phe}$, at temperature from 25 to $40^{\circ}C$, in the presence of 0.1 M NaCl and various low levels of added magnesium ion. The exchange rates in zero $Mg^{2+}$ concentration indicate early melting of acceptor stem, D stem, and tertiary structure. Addition of magnesium ion stabilizes the entire D stem more effectively than any other secondary or tertiary interactions.