• Title/Summary/Keyword: 암산

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Synthesis and Characterization of New Positive Type Photosensitive Poly(amic acid)s (신규 양성형 감광성 폴리암산의 합성 및 특성 연구)

  • Sim Hyun-Bo;Yu Yeong-Im;Yi Mi-Hye
    • Polymer(Korea)
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    • v.30 no.2
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    • pp.162-167
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    • 2006
  • Polyamic acid (PAA) was prepared from cyclobutane-1,2,3,4-tetracarboxylic dianhydride (CBDA) and 4,4'-fiaminodiphenyl ether (DDE). In order to impart a photosensitivity to the PAA, diazonaphthoquinone (DNQ) derivative (DI) was added. However, the addition of the DI was not enough to inhibit the dissolution of the PAA for a aqueous alkal solution. Therefore, we had synthesized poly(amic acid ester)s by an adding 1,2-epoxy-3-phenoxypropane to the PAA. That is, an acidity of the PAA could be controlled by an esterification reaction of 1,2-epoxy-3-phenoxypropane with the PAA. Significant difference of a dissolution rate of the poly(amic acid ester) between an o(posed and unexposed area was observed at an acid content of 60% and less. Resolution of the positively patterned film showed about $25{\mu}m$ at the exposure dose of $200mJ/cm^2$.

Vegetation Structure of Mountain Ridge from Bubong to Poamsan in Baekdudaegan, Korea (백두대간 부봉-포암산 구간의 식생구조)

  • Chu Gap Cheol;Kim Gap Tae
    • Proceedings of the Korean Society of Environment and Ecology Conference
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    • 2005.04a
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    • pp.21-32
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    • 2005
  • To investigate the vegetation structure of mountain ridge from Bubong to Poamsan, 16 plots$(400m^2)$ set up with random sampling method were surveyed. Three groups Quercus mongolica-Pinus densiflora community, Quercus variabilis-Pinus densiflora-Quercus mongolica community were classified by cluster analysis. Quercus mongolica was found as a major woody plant species in the ridge area from Bubong to Poamsan, and partly in lower elevation was occupied by Quercus variabilis and Pinus densiflora. High positive correlations was proved between Lespedeza maximowixcii and Pinus koraiensis, Fruxinus sieboidiana and Rhododendron mucronulatum, Acer mono and Weigela subsessilis, and relatively high negative correlations was proved between Symplocos chinensis for. pilosa and Fraxinus sieboldiana, Rhododendron mucronulatum Species diversity(H') of investigated groups were ranged $0.9066\~1.0821$, and it was relatively low compared to those of mountain ridge area of other national parks.

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Vegetation Structure of Mountain Ridge from Bubong to Poamsan in Baekdudaegan, Korea (백두대간 부봉-포암산 구간의 식생구조)

  • Choo Gab-Cheul;Kim Gab-Tae
    • Korean Journal of Environment and Ecology
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    • v.19 no.2
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    • pp.83-89
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    • 2005
  • To investigate the vegetation structure of mountain ridge from Bubong to Poamsan, 16plots$(400m^2)$ set up with random sampling method were surveyed. Two groups of Quercus mongolica-Pinus densiflora community, Quercus variabilis-Pinus densiflora-Quercus mongolica community were classified by cluster analysis. Quercus mongolica was a major woody plant species in the ridge area from Bubong to Poamsan, and Quercus variabilis and Pinus densiflora were partly occupied in lower elevations. High positive correlations were proved between Lespedeza maximowixcii and Pinus koraiensis, Fraxinus sieboldiana and Rhododendron mucronulatum, Acer mono and Weigela subsessilis, and relatively high negative correlations were proved between Symplocos chinensis for. pilosa and Fraxinus sieboldiana, Rhododendron mucronulatum. Species diversity(H') of investigated groups were ranged from $0.9066\~1.0821$, and it was relatively low value compared to that of mountain ridge area of other national parks.

Pyran and Pyridine as Building Blocks in Heterocyclic Synthesis (이중고리 합성에 블록제로서 이용된 피란과 피리딘)

  • El-Hashash, Maher.A.;El-Sawy, Abdallah.A.;Eissa, Abdelmonem.M.F.
    • Journal of the Korean Chemical Society
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    • v.53 no.3
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    • pp.308-324
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    • 2009
  • The present work is devoted to study the interaction of $\beta$-aroylacrylic acid derivative (3) with malononitrile in (DMF) in the presence of piperidine and/or ammonium acetate, then using the formed compounds as starting materials for synthesizing fused and isolated heterocyclic systems. It has been established that the $\beta$-aroylacrylic acid (3) reacts with malononitrile in (DMF) in the presence of piperidine as a catalyst with the formation of 4H-pyran derivative (4). By changing the catalyst into ammonium acetate, pyridine derivative (5) has been obtained. Also the N-maleamic acid derivatives (19) and (27) have been synthesized via the interaction of (4) and (5) with maleic anhydride. The purpose of this step is to study the behavior of the formed maleamic acid derivatives – as analogies of $\beta$-aroylacrylic acids – towards different active methylene compounds under Michael addition reaction.

Floristic study of Mt. Jaamsan in the Gyeongsang supergroup, Korea (경상누층군 자암산의 관속식물상)

  • Kim, Jung-Hyun;Park, Hwan-Joon;Nam, Gi-Heum;Lee, Kyeong-Ui;Kim, Jin-Seok
    • Korean Journal of Environmental Biology
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    • v.37 no.3
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    • pp.229-248
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    • 2019
  • This study was carried out to investigate the flora of Mt. Jaamsan on the Gyeongsang supergroup, Korea. From the results of eight field surveys from March to October 2017, we have identified 530 total taxa, representing 483 species, eight subspecies, 35 varieties, two forms, and two hybrids, which were placed in 325 genera and 110 families. The plant formation of Mt. Jaamsan is the deciduous broad-leaved and conifer mixed forests, which are the common ones in the middle part of the Korean Peninsula. Most of the mountain is covered with young secondary forest, which is mainly composed of Quercus spp., and Pinus. Out of these 530 taxa, 12 are endemic to Korea, 17 taxa are listed on the Korean Red List of threatened species, 65 are floristic target species, and 55 are invasive alien species. The percentage of naturalized index(NI) and urbanization index (UI) were 10.4% and 17.2%, respectively. Mt. Jaamsan has a high plant diversity, including endemic and rare species, which consist of geomorphological landscapes. We considered that the composition and distribution of species are affected by the different environmental factors according to the sedimentary rocks, drying ridges, valleys, and streams. Together with the rocks and soils were the substrate type that play a major role in providing the unique habitats for sun plants in the area.

전남 장성군 꿩 샤브샤브

  • Seo, Tae-Gyeong
    • 건강소식
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    • v.29 no.10 s.323
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    • pp.38-39
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    • 2005
  • 예부터 호남에서는 아무 음식점이나 들어가도 실패하지 않는다는 말이 있을 정도로 맛에 관한 한 다른 지역과의 비교를 불허한다. 그 중 백암산 줄기에 몸을 기대고 있는 장성군은 먹거리 뿐만 아니라 천년고찰인 백양사와 서원, 홍길동 유적지 등 다양한 볼거리를 갖춘 곳. 매년 봄에는 홍길동 축제가, 가을에는 백양단풍축제가 여행객들을 반긴다.

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Comparision of Monoterpene in Ambient Air at Forest and Essential Oil (숲속 공기와 주변 우점수목 정유의 모노테르펜류 분포 비교)

  • Oh, Gil-Young;Seo, Yun-Gyu;Park, Gui-Hwan;Kim, Ik-San;Bae, Ju-Soon;Park, Song-In;Ha, Hun;Yang, Soo-In;Lee, Ji-Hun;Lee, Wan-Jin
    • Journal of Korean Society of Forest Science
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    • v.102 no.3
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    • pp.309-314
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    • 2013
  • The concentration of terpene (18 species) was measured from spring to fall in ambient air and essential oil at three different forests located in Jeollanamdo province. Sampling was conducted at 4-hour-interval a day of each season. In the ambient air, ${\alpha}$-pinene, ${\beta}$-pinene and 2-carene were the most abundant compounds throughout the sampling periods and areas. The highest three-season average concentration of total terpene was 2,597 pptv at Jeamsan(Mt.) in Boseong which was predominantly populated by Pinaceae. The seasonal averages were observed to peak during spring with their max at Palyeongsan(Mt.) in Goheung and Jeamsan(Mt.) in Boseong, and during fall at Woodland in Jangheung. Most of terpenes had diurnal variations with higher concentrations during the daytime, and lower during the nighttime. However in essential oil, the highest annual average concentration of total terpene was $798{\mu}g/dry-g$ at Goheung which was predominantly populated by Chamaecyparis obtusa. Also, the component proportion ratio showed different distribution between ambient air and essential oil. From the results of this study, we suggest that Chamaecyparis obtusa species is more useful, and younger tree is more economical than older one, and spring is the best season for lumbering in order to use essential oil.

K-Ar ages and Geochemistry for Granitic and Volcanic Rocks in the Euiseong and Shinryeong Area, Korea (의성-신령지역의 화강암류 및 화산암류에 대한 K-Ar 연대)

  • Kim, Sang Jung;Lee, Hyun Koo;Itaya, Tetsumaru
    • Economic and Environmental Geology
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    • v.30 no.6
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    • pp.603-612
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    • 1997
  • Cretaceous sedimentary-volcanoclastic formations of the Kyeongsang Supergroup were intruded by granitic rocks in the late Cretaceous and early Tertiary. In the Euiseong and Shinryeong area, these intrusives have various compositions including gabbro, diorite,biotite granite and feldspar porphyry. Associated volcanic rocks consist of two chemically distinct types: the bimodal suite of basalt and rhyolite in the Keumseongsan caldera, and the felsic suite of andesite and rhyolite in the Sunamsan-Hwasan calderas. Most rocks are subalkaline, and follow a typical differentiation path of the calc-alkaline magma. The granitic rocks can be distinguished chemically from the volcanics by high Zr/Y ratios. Differences in Zr/Y and K/Y ratios between the two volcanic suites can be accounted for by mantle source and fractionation. Chondrite-normalized trace element abundances of granitic rocks are depleted in Th and K, whereas those of the Keumseongsan rhyolites are depleted in Sr and Ti. Rb, La and Ce is enriched in rhyolites of the Sunamsan-Hwasan calderas. $Rb-SiO_2$ and Rb-Y+Nb discrimination diagrams suggest that the intrusives and volcanics have a volcanic arc setting. K-Ar ages indicate four plutonic episodes : diorite (89 Ma), granite (66~62 Ma), granite and porphyry (55~52 Ma) and gabbro (52~45 Ma), and two volcanisms : bimodal basaltic and rhyolitic volcanism (71~66 Ma) in the Keumseongsan caldera, and felsic andesitic and rhyolitic volcanism (61~54 Ma) in the Sunamsan-Hwasan calderas. Geochemical and age data thus suggest that the igneous rocks are related to several geologic episodes during the late Cretaceous to early Tertiary.

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The Analysis on the Forest Community of Raised Bog in Mt. Daeam (대암산(大岩山) 고층습원(高層濕原) 주변(周邊)의 산림군집(森林群集) 분석(分析))

  • Song, Ho Kyung;Kwon, Ki Won;Yim, Kyong Bin;Cheong, Jin Cheol;Jang, Kyu Gwan
    • Korean Journal of Agricultural Science
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    • v.20 no.2
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    • pp.145-152
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    • 1993
  • Vegetational data obtained from 15 quadrats of Mt. Daeam area were analysed by applying two multivariate methods : two-way indicator species analysis(TWINSPAN) for classification and detrended canonical correspondence analysis(DCCA) for ordination. The dominant tree species were Quercus mongolica, Acer pseudo-sieboldianum, Betula costata, and Acer mono in descending order. The pH ranges were 5.0 to 5.5 in the 15 sites near bog and 5.3 to 5.4 in the 3 sites within bog. The forest communities in Mt. Daeam were classified into Quercus mongolica-Acer mono, Quercus mongolica-Prunus sargentii, Quercus mongolica-Abies nephrolepis-Acer tschonoskii var, rubripes, and Quercus mongolica-Abies nephrolepis-Betula costata according to the TWINSPAN. The relationships between the distribution of dominant species of forest vegetation and soil in the forest of Mt. Daeam were investigated by analyzing soil nutrition gradient. Quercus mongolica-Prunus sargentii forests were distributed in the good sites in nutrition levels of total nitrogen, cation exchange capacity, $Mg^{+{+}}$ and $Ca^{+{+}}$ but Quercus mongolica-Abies nephrolepis-Betula costata forests in the poor sites in the nutrition levels.

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