• 제목/요약/키워드: External Morphology

검색결과 288건 처리시간 0.024초

A Study on Long-Term Cycling Performance by External Pressure Change for Pouch-Type Lithium Metal Batteries

  • Seong-Ju Sim;Bong-Soo Jin;Jun-Ho Park;Hyun-Soo Kim
    • Journal of Electrochemical Science and Technology
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    • 제15권2호
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    • pp.314-320
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    • 2024
  • Lithium dendrite formation is one of the most significant problems with lithium metal batteries. The lithium dendrite reduces the lithium metal batteries' cycling life and safety. To apply consistent external pressure to a lithium metal pouch cell, we design a press jig in this study. External pressure creates dense lithium morphology by preventing lithium dendrite formation. After 300 cycles at 1 C, the cells with the external pressure perform far better than the cells without it, with a cycling retention of 97.8%. The formation of stable lithium metal is made possible by external pressure, which also enhances safety and cyclability.

강도래과(강도래목) 2 종에 대한 성충 및 란의 외부형태 관찰 (Observation of the Adults and Eggs of Two Species of the Family Perlidae(Plecoptera) to Korea)

  • 나철호;백순기;조영관
    • Animal Systematics, Evolution and Diversity
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    • 제7권1호
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    • pp.101-110
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    • 1991
  • 1989년과 1990년의 봄철에 전남,북과 경남일원의 신간계류에서 채집된 강도래 과의 Oyamia coreana Okamoto와 Kiotina decorata(Zwick) 2종에 대한 성충의 외부형태와 난의 전자현미경에 의한 미세구조 관찰을 실시하였다.

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한국 고유식물의 종속지 IX. 장구채속식물의 분류와 종간유연관계 (Monographic Study of the Endemic Plants in Korea IX. Taxonomy and interspecific relationships of the genus Melandrium)

  • 정영호
    • Journal of Plant Biology
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    • 제31권1호
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    • pp.51-68
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    • 1988
  • To clarity the species of genus Melandrium (Caryophyllaceae) in Korea, the taxonomic characters were described and interspecific relationships were discussed to the extemal morphology with light and scanning electron microscopy. The position and size of appendages on petal, the shape and venation pattern of leaf, and the external morphology of seed and pollen were approved as the good characters to classify genus Melandrium in Korea. As the result, genus Melandrium in Korea could be arranged as 6 species, 1 variety, 1 forma. M. umbellatum was exclusively distributed in north Korea, and its taxonomic treatment was reserved.

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2종 천남성(天南星)의 외부(外部) 및 내부형태(內部形態)에 대한 연구 (The external and internal morphological standard of original plants and herbal states in 2 kind of Arisaematis Rhizoma)

  • 김홍준;윤주봉;주영승
    • 한국한의학연구원논문집
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    • 제12권2호통권17호
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    • pp.63-73
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    • 2006
  • In the original plant of Arisaematis Rhizomas, the features of external and internal shape of Arisaema amurense var. serratum $N_{AKAI}$ and A. amurense $_{MAXIM}$. are as follows. 1. In the external shape of original plant, Arisaema amurense var. serratum $N_{AKAI}$ has high stem, an oval-elliptic leaflet and a serrate leaf margin. But A. amurense $M_{AXIM}$ has a relatively low stem, an upside oval leaflet and no serrate leaf margin. 2. On the herbs character of original plant, Ansaema amurense var. serratum $N_{AKAI}$ is small in height and diameter, but A. amurense $M_{AXIM}$ is relatively large in height and diameter. 3. On the gathered herbs character of original plant, the section of Arisaema amurense var. serratum $N_{AKAI}$ is brightly white, easily spilt and strong scent. But the section of A. amurense $M_{AXIM}$ is thin yellowish brown, not easily spilt and weak scent. Also the grade of gathered herbs, both can be classified by diameter and external scent. 4. In the current herbs character, Korean and Sichuan Province products are irregullar shape and have no scent, Jilin Province products are regular shape. Also, Guangxi Province products are small size and concave in one side, Hebei Province products are irregular size and shape. 5. In internal shape of original plant, epidermal cell of Arisaema amurense var. serratum is very tight. With the except of micro difference in parenchyma cell of cortex, on the whole there are nearly no differences with A. amurense $M_{AXIM}$. Also, samely in the internal shape, according to collecting sites, epidermis exhibits a lot layer in curving state and secreting duct is developed and vascular bundle and exists between parenchyma cell of cortex. In the future, additional study is needed to distinguish herb and effect between same genus-degree of relatedness.

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독활(獨活)의 외부(外部) 및 내부형태(內部形態)와 이화학패턴연구 (A Study on Internal-External Morphology and Pattern Analysis in Angelicae Pubescentis Radix)

  • 김홍준;김자영;최고야;정승일;주영승
    • 한국한의학연구원논문집
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    • 제12권3호통권18호
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    • pp.101-115
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    • 2006
  • The purpose of this study was to introduce the differential standard of the types of Angelicae Pubescentis Radix. We established the classificatory standard according to the external and internal morphology and the physicochemistrical pattern for the four types of Aucklandiae Radix. The results follow: 1. At the external shape, Angelica pubescens f. biserrata has rising lenticel and dark brown surface, Its section is light gray and its xylem is yellow gray. Aralia continentalis has big stem mark in upper portion, its section has no dense tissue with yellow gray. Heracleum hemsleyanum has dark brown surface and little lenticel, its cortical layer is white yellow and xylem is isabella and powdered. 2. At the internal shape, Angelica pubescens f. biserrata has phloem with half of the root and rare vessel. Aralia continentalis has phloem with two-thirds of the root and it has broad cutting and putting vessel that formed 1-2 row. Heracleum hemsleyanum also has phloem with half of the root and wide scattered latex tube and many large vessel. 3. At the TLC pattern, Heracleum hemsleyanum has remarkable dark spot at $R_{f}$ 0.23 on the sulphuric acid color pattern test, but others have faint. 4. At the HPLC pattern, all samples have generally patterns. But Angelica pubescens f. biserrata shows diminutive continentalic acid content and the peak at Rt 20.278min comes out on Heracleum hemsleyanum, but do not come out on Aralia continentalis and Angelica pubescens f. biserrata. Heracleum hemsleyanum has remarkable peak at Rt 20.278min, but shows no peak at Rt 29.023min unlike Aralia continentalis or Angelica pubescens f. biserrata. Also Aralia continentalis and Angelica pubescens f. biserrata show one remarkable peak at Rt 29.023, but Heracleum hemsleyanum do not show. Consequently, Aralia continentalis and Angelica pubescens f. biserrata are comparable whit continentalic acid content and Heracleum hemsleyanum is comparable with the peak at Rt 20.273 and Rt 29.023. So it is thought that content of continentalic acid and the peaks at Rt 20.278 and Rt 29.023 can apply to differentiate a species from other. It is considered the results of this study will be furnished the basis to succeeding studies and it is needed to extensive comparative study for the same genus-degree of relatedness.

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담죽엽(淡竹葉)과 죽엽(竹葉)의 기원(起源)에 관한 문헌적(文獻的) 고찰(考察)

  • 김재환;주영승
    • 대한한의학회지
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    • 제17권2호
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    • pp.5-16
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    • 1996
  • For distinguish between Lophatherum gracile and Phyllostachys nigra var. henonis based on natural shape and external-internal morphology of medicinal shape, general contents of oriental medicine were rearranged through bibliography. As a result, two medicinal stuffs indicated the difference in shape and structure(external-internal and powder)of origin plant bibiliographically. After this, this contents were utilized to give proof of many effective difference between two medicinal stuff.

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Micromorphology of Benthic Diatom Species Achnanthes alteragracillima Lange-Bert

  • Lee, Jung Ho
    • Journal of Plant Biology
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    • 제37권4호
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    • pp.417-420
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    • 1994
  • Morphology of Achnanthes alteragracillima Lange-Bert. was studied with scanning electron microscopy in epilithic samples from the Kwang River (Kwangchun), Kyungsangbuk-Do, Korea. The species was characterized by the external raphe terminal fissure deflecting up to valve margin, the internal raphe proximal endings slightly deflecting to the opposite direction each other and biased hyaline area at the valve pole. It could be distinguished from A. minutissima K tz., closely related species, in having not straight external raphe terminal fissures, and from A. convergens H.Kob. in having a biased hyaline area at the valve pole and not a convergent striae arrangement at the pole of the raphe valve.

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한국산 용담과 쓴풀속(Ophelia) 식물의 분류 1. 외부형태 및 분포 (A taxonomic study of the Ophezia(Gentianaceae) in Korea 1. External morphology and distribution)

    • 한국자원식물학회지
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    • 제12권4호
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    • pp.324-339
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    • 1999
  • 한국산 쓴풀속(용담과) 식물 중 남한에 분포하는 5분류군과 변이체라 생각되는 1분류군, 총 6분류군에 대하여 외부형태학적 형질을 재검토하였고 판별분석(44개의 양적형질)을 수행하여 절과 종간의 한계를 분명히 하여 종 동정의 어려움을 해결하고 분류학적 위치를 설정하고자 본 연구를 수행하였다. 또한 북한에 분포하는 1분류군은 동경대학의 소장품을 관찰하여 분류군의 기재에만 사용하였다. 조사결과, 밀선의 전체적 형태, 화관과 꽃받침의 열편수에 의해 2개 절로 구분되었으며 경생엽의 형태와 화관의 색과 무의에 의해 종간 구분이 가능하였다. 변이체라고 생각되었던 큰잎쓴풀(화관 열편에 자색 점무의를 갖는 분류군) A형은 자색 점 이외의 형질들에서는 전혀 차이를 찾아볼 수 없어 모종의 변이 폭에 넣는 것이 타당하다고 생각된다. 판별분석에 의해 쓴풀속의 식물들을 구별하는 중요한 양적형질은 화관에 관여하는 형질들임이 밝혀졌다. 종자의 형태와 종피의 형질은 종이상을 구별하는 매우 유용한 형질로 밝혀졌다. 따라서 한국산 쓴풀속 식물들에 대한 종 동정의 어려움을 해결하였으며, 속내의 분류학적 위치를 명확히 하였다.

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Gnaphalium tranzschelii Kirp. (Asteraceae): An unrecorded species from Korea

  • Lee, Dong Hyuk;Byeon, Jun Gi;Heo, Tae Im;Park, Byeong Joo;Lee, Jun Woo;Kim, Ji Dong;Choi, Byoung Hee
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2019년도 춘계학술대회
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    • pp.78-78
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    • 2019
  • Gnaphalium L. is a small herbaceous genus comprising up to 80 species in worldwide (Asia, North to South America, Africa, and Oceania). This genus is highly polymorphic which embrace uncommon broad morphological boundary, and thus further studies were needed to proper taxonomic delimitations for the genus and its relatives. Gnaphalium uliginosum L. was usually found in moist sites such as margins of lake, pond, reservoir, stream banks and paddy field. This squat plant is solely known species in Korean Gnaphalium. During the revisionary study of the tribe Gnaphalieae (Asteraceae) in Korea, however, we found several materials in domestic herbaria (e.g., SNU, KWNU) that identified as G. uliginosum or Gamochaeta pensylvanica (Willd.) Cabrera collected from central to northern Korea, but clearly differ to the morphology of G. uliginosum. The external morphology of the materials is seemingly the only feature at odds with G. uliginosum. However, its morphological characters such as tall erected stems (ca. 30cm), hairs on seeds and whitish tomentose hairs on the whole plants are easily distinguished from G. uliginosum, and rather it looks like G. tranzschelii Kirp. Although the name G. tranzschelii have been treated as synonym of G. uliginosum by several authors, its distinct morphology might be sufficient to separate to two independent taxa. Generally, the morphological polymorphisms and hybridization of G. uliginosum complicate the taxonomy of the species, and thus further investigation for their habitat, distribution and morphology were needed to their taxonomic entity.

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