• Title/Summary/Keyword: photomicrographs

검색결과 90건 처리시간 0.027초

종이의 물성에 영향하는 섬유특성의 정량적 해석(II) (Quantitative Analysis of Pulp fiber Characteristics that Affect Paper Properties (II))

  • 이강진;박종문
    • 펄프종이기술
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    • 제32권2호
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    • pp.35-39
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    • 2000
  • Refining is very important process of fibers treatment for proper paper properties. An extent of refining is usually measured by freeness, although freeness gives complicated meanings. One of a direct way of studying the refining effects on pulp fibers is making photomicrographs of beaten fibers. The conventional microscopy like light microscopy(LM) and scanning electron microscopy(SEM) require to preserve the wet structure of pulp fibers morphologically since most of papermaking process is carried out almost entirely in water. Recently developed microscopy, especially confocal laser scanning microscopy(CLSM), offers the possibility of examining fully hydrated pulp fibers. Cross-sectional images of wet pulp fibers are also generated using optical sectioning by CLSM and image analysis in order to verify and quantify the extent of fiber wall swelling indicating the internal fibrillation. At low beating load such as 2.5 kgf, in the same freeness, breaking length is higher than that of high beating load such as 5.6 kgf. fiber wall thickness at low beating load is greater than that at high beating load. This result is accounted for the fact that internal fibrillation in the low beating load was high.

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마이크로에멀젼을 이용한 AgBr 나노입자의 제조 (Preparation of Nano AgBr Particles by Microemulsions)

  • 정노희;김홍수
    • 한국응용과학기술학회지
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    • 제21권1호
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    • pp.17-23
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    • 2004
  • Silver bromide particles from 50 to 200${\AA}$ in diameter are prepared by mixing two microemulsions contaning the precursor salts $AgNO_3$ and KBr. The microemulsions are composed of AOT(bis(2-ethylhexyl) sodium sulfosuccinate), n-heptane and water. The particle diameters are measured on photomicrographs obtained by transmission electron microscopy. The size of the particles is generally larger than that of the water cores. The influence of both the concentration of precursor salts in the water cores of the microemulsoin and the size of these water cores on the size of the particles has been studied.

Scaptognathus teuriensis, a New Record of Halacarid Mite (Acari, Halacaridae) from Dokdo Island of Korea

  • Lee, Jimin;Chang, Cheon Young
    • Animal Systematics, Evolution and Diversity
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    • 제33권1호
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    • pp.45-50
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    • 2017
  • A halacarid species of Scaptognathus teuriensis $Ab{\acute{e}}$ is recorded from Korea on the basis of the specimens collected from littoral sandy sediments at Dokdo Island, the easternmost island off Uleung Island of South Korea. Korean specimens coincide well with the key characters in the original description for types from Hokkaido, Japan, such as male genitoanal plate comprising only pars sclerosum, bipartite female genitoanal plate with six perigenital setae, rounded posterior margin of anterior dorsal plate, second and fifth dorsal setae both positioned at membranous cuticle, leg chaetotaxy of bipectinate setae on tibiae I-IV of 4-2-2-2, and tarsi of all legs armed with paired large lateral claws with accessary teeth and small median claw. Redescription based on Korean specimens and scanning electron microscope photomicrographs are provided herein. This is the first record of the genus from Korea.

A New Gastrotrich Species of the Genus Ptychostomella (Macrodasyida, Thaumastodermatidae) from South Korea

  • Lee, Ji-Min;Hwang, Ui-Wook;Chang, Cheon-Young
    • Animal cells and systems
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    • 제13권1호
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    • pp.25-30
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    • 2009
  • A new marine gastrotrich species, Ptychostomella jejuensis n. sp. belonging to the family Thaumastodermatidae, is described on the basis of the specimens from subtidal sand bottom at about 6-7 m depth of Jeju Island, South Korea. Ptychostomella jejuensis n. sp. is distinguished from its congeneric species with smooth cuticular armature by the character combination: (1) small body up to about 160 ${\mu}m$ in length; (2) presence of knob-like cephalic tentacles; (3) absence of dorsal and ventral adhesive tubes; (4) bifid pedicles; (5) pyriform copulatory organ. Under scanning electron microscopy, numerous epidermal gland openings were observed in the new species, characteristically flanking a bristle. Taxonomic accounts on the affinities, some brief remarks on the epidermal gland openings and the cooccurrence with P. orientalis Lee and Chang, 2003 are also presented with detailed illustrations and scanning electron photomicrographs.

전자레인지의 Ceramic Coating이 채소류의 마이크로파 데치기에 미치는 영향 (Effects of Ceramic Coating for Microwave Blanching on Vegetables)

  • 금준석;한억
    • 한국식품영양과학회지
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    • 제25권6호
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    • pp.951-957
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    • 1996
  • 당근, 쪽파, 시금치와 같은 채소류에 대한 데치기 실험에서 데치기 시간은 전자레인지 CCT가 빨랐으며, 색도 및 절단강도 변화에서는 데치기 처리로 명암도, 적녹도, 황청도, 절단 강도가 대조구에 비하여 감소하였으며 그 감소 폭은 전자레인지 CCT의 경우가 적었다. 미세구조 관찰에서는 전자레인지 CCT가 NCCT보다 조직 구조가 덜 파괴하는 것으로 나타났으며, vitamin C 함량에서도 전자레인지 CCT가 손실이 적었다.

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고온 등온환경하의 탄소섬유/에폭시 단일방향 복합재료의 열화 예측모델 개발 (Study on Thermal Degradation Behavior of Unidirectional Carbon Fiber/Epoxy Composite Due to Isothermal Environment)

  • 정기모;최흥섭;김창호;한중원;남재도
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2002년도 추계학술발표대회 논문집
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    • pp.43-47
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    • 2002
  • Weight loss experiments have been performed for unidirectional carbon fiber/epoxy laminates under both isothermal and cyclic thermal conditions. It was found that weight losses were the result of both specimen-geometry dependent oxidative degradation and volumetric geometry dependent thermal degradation. Thermal degradation was found to play a major role in the overall weight loss process, and photomicrographs of cross-sectioned, aged specimens confirmed this fact. A method to predict the effect of isothermal environment on the weight loss was introduced and found to be in good agreement with experimental data at temperatures near Tg (glass transition temperature).

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마이크로파 가열에 의한 고구마의 가공 특성 (Effects of Microwave Heating on Processing of Whole Sweetpotatoes)

  • 금준석;;한억
    • 한국식품조리과학회지
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    • 제10권2호
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    • pp.138-141
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    • 1994
  • Whole, peeled sweetpotatoes were subjected to four different processes: 15 min microwave heating followed by 15 min baking (1), 90 min baking (2), 15 min microwave heating (3), and 15 min boiling followed by 15 min microwave heating (4). Samples of green and cured roots were used in the study. Scanning electron photomicrographs revealed that cured roots contained larger numbers of starch granules in the parenchyma cells than green roots, most of them compounded. The starch in cooked green roots was gelatinized while for cured roots it was mostly hydrolyzed into dextrins and sugars. Starch in process (3) roots was mostly gelatinized while in process (1) and process (2) roots gelatinized starch appeared in little quantity, thus it was primarily converted to dextrins and sugars. The process (4) resulted in little conversion of starch. The process (1) product resulted in a similar product to the process (2) product.

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A New Species of Cletocamptus Copepoda (Harpacticoida, Canthocamptidae) from Salt Marshes in Korea

  • Chang, Cheon Young
    • Animal Systematics, Evolution and Diversity
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    • 제29권3호
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    • pp.227-237
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    • 2013
  • A new copepod species, Cletocamptus koreanus, is described from estuaries and salt marshes on south and southwest coasts in Korea. Cletocamptus koreanus n. sp. evidently belongs to C. deitersi species group in sharing 6-segmented antennule, 3 setae on antennary exopod, leg 1 with endopod shorter than exopod, and 2+1 inner setae on the third exopodal segments of legs 3-4. However, C. koreanus is distinguished from its allied congeneric species by different setal armatures of mandibular palp, antennary exopod, endopod of female leg 2 and the third exopodal segments of legs 3-4, and relative length and shape of apophysis of male leg 3 enp 2. Description and taxonomic accounts of the new species are presented herein, with detailed illustrations and scanning electron microscope photomicrographs. Discussion on the affinities with other species of C. deitersi group are provided, along with brief comments on the morphological discrepancies between the new species from Korea and other Asian species from China and India.

마이크로파 재가열이 쌀밥의 품질에 미치는 영향 (Effect of Microwave Reheating on the Quality of Cooked Rice)

  • 금준석;한억;김용환
    • 한국식품영양과학회지
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    • 제25권3호
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    • pp.504-512
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    • 1996
  • Changes in quality of cooked rice after microwave reheating were evaluated. Ceramic coated microwave oven reduced a reheating time(1 min). Storage temperature, storage time and microwave reheating did not affect the color value of cooked rice after microwave reheating. Hardness of cooked rice after microwave reheating decreased in frozen storage treatment. Photomicrographs of cross-section of cooked rice after microwave reheating showed restoration of starch. Effect of storage temperature and time were not significant in appearance, aroma, taste and texture of cooked rice after microwave reheating for sensory evaluation test.

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Redescription of the Free-living Marine Nematode Species, Draconema japonicum Kito, 1976 (Nematoda: Draconematidae), by Scanning Electron Microscopy

  • Rho, Hyun-Soo;Kim, Won
    • Animal cells and systems
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    • 제8권4호
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    • pp.235-245
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    • 2004
  • Numerous specimens of adults and juveniles of Draconema japonicum Kito, 1976 have been found in intertidal and subtidal sediments and various algae around coast of South Korea. Draconema japonicum is recognized by the following characteristics: having an elongated loop-shaped amphideal fovea in male and horseshoe-shaped amphideal fovea in female, two pairs of uniformly tapered sublateral anal setae and two pairs of unevenly tapered subventral anal setae in male, eight to ten pairs in male and 13 to 15 pairs in female of posterior sublateral adhesion tubes, and five to six pairs of somatic setae on non-striated tail region. Scanning electron photomicrographs of the species are presented with a detailed morphological description and a key to the species of the genus Draconema Cobb, 1913. This is the first discovery of D. japonicum outside the Japanese waters.