• Title/Summary/Keyword: sessile

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A Numerical Method for Determining Surface Tension of Sessile Drop (Sessile Drop의 형상으로부터 수치계산에 의한 표면장력 측정)

  • ;Takayoshi Iseki
    • Journal of the Korean Ceramic Society
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    • v.33 no.12
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    • pp.1325-1330
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    • 1996
  • A new numerical method for determining the surface tension of a liquid drop by experimental measurement of the contour of the sessile drop is explained. in the present method a very simple and short computer program enables the calculation of surface tension in a few seconds even by a low speed personal computer. It need not the use of any other numerical tables or complex techniques. X and Z-corrdinates at one point on the contour of a sessile drop and the tangential angle at that point are all the data needed when the density of the drop is known. The results were compared with the values derived by a conventional method. This method can be used for the confirmation of measuring accuracy. Also the same concepts can be applied for the pendant drop method by changing only the sign of Z-coordinate from "+" to "-"ot; to "-"ot;-"quot.

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First Record of One Sessile Ctenophora, Lyrocteis imperatoris, and Its Embryos from Korea

  • Song, Jun-Im;Hwang, Sung-Jin
    • Animal Systematics, Evolution and Diversity
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    • v.25 no.3
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    • pp.255-259
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    • 2009
  • The sessile ctenophores, Lyrocteis imperatoris Komai, 1941 were collected for the first time from Garinyeo, offshore Seogwipo of Jejudo Island by SCUBA diving on June 18, 2009. This species distributed in West North Pacific was newly recorded in Korean waters. Its embryos in various developmental stages were observed in the internal brood chamber.

Community structure of sessile organisms on PVC plates according to different submerged timings and durations in Jangmok Bay, Korea (남해 장목만에서 PVC판 투입시기와 투입기간에 따른 부착생물군집 구조)

  • Park, So-Hyun;Seo, Jin-Young;Choi, Jin-Woo
    • The Korean Journal of Malacology
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    • v.27 no.2
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    • pp.99-105
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    • 2011
  • This study was conducted to compare the species composition of sessile organisms on the artificial substrates of PVC submerged at different time intervals and duration in Jangmok Bay, Geoje Island, southern coast of Korea. Three PVC plates were submerged at one month interval from March to October and retrieved in November, 2007. A mussel, Mytilus galloprovincialis exclusively occupied the artificial substrates submerged from March to April and occurred as a dominant species to July. An ascidian, Styela plicata occurred as a dominant sessile species from May to August. Balanus amphtrite, Bugula sp., and hydrozoans occurred as dominant species on the plates submerged from July to September. There was a mis-match between the peak time of settlement and dominance of sessile organisms due to the interspecies competitions when the PVC plates were retrieved in November. There was no clear relationship between submerged duration and the abundance of sessile organisms due to the different settlement period. M. galloprovincialis seemed to be a strong competitor which could exclude the previous recruiters of macroalgae by overgrowth and occupy the substrate surface and maintain its high population density by preventing the settlement of other species until late autumn. These results suggested that the composition of sessile organisms in vacant hard substrates could be determined by the combined effects of supply-timing of larvae and post-settlement competitions.

The effect of dead coral skeletons on the water quality and sessile mollusks in the closed system (폐쇄시스템 내에서 죽은 산호골격이 수질과 고착성 연체동물에 미치는 영향)

  • Lee, Nam Hyeon;Han, Kyung Nam
    • The Korean Journal of Malacology
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    • v.28 no.3
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    • pp.187-196
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    • 2012
  • Recently, for the purpose of constructing artificial ecosystem, the public aquarium and experimental mesocosm systems are receiving attention. To design and establish an aquarium and mesocosm system, there is need of several materials for simulating the environment, such as sediments, rocks, and plants. Expecially for sessile mollusks, there must be proper materials to which sessile invertebrates can adhere. Nowadays, many aquariums and mesocosm systems are using dead coral skeletons for sessile mollusks. This study was proceeded to have data on the effect of dead coral skeletons on water qualities with the experiment on the environmental factors. For this purpose, I made glass tank for experiment, chose two types of dead coral skeletons imported from the Indonesia and observed the change of water qualities and decomposition efficiency of TAN (total ammonia-nitrogen), nitrite ($NO_2{^-}$) and nitrate ($NO_3{^-}$). As a result, the lager the surface area was, the more TAN, nitrite and nitrate decomposition rate increased. In addition, coral skeletons covered with crustose algae and bacteria in the tank showed faster TAN, nitrite and nitrate removal rate and stabilization. Accordingly, this experiment suggested that dead coral skeletons could be used as a sub filter for the closed system as well as an adhering plate.

Stem Rot of Disporum sessile Caused by Sclerotium rolfsii in Korea (Sclerotium rolfsii에 의한 윤판나물 흰비단병)

  • Kwon, Jin-Hyeuk;Shim, Chang-Ki;Park, Chang-Seuk
    • Research in Plant Disease
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    • v.13 no.1
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    • pp.50-52
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    • 2007
  • From 2004 to 2005, the stem rot of Disporum sessile D. $D_{ON}$ caused by Sclerotium rolfsii occurred spoyadieally in an herbs exhibition farm of Hamyang, Gyeongsangnam-do Agricultural Research and Extension Services, Korea. The typical symptom is water-soaking, dark brown on the stem and rotting, wilting. The infected plants were mostly died. White mycelial mats were spread over lesions, and then sclerotia were formed on stems and near soil line. The sclerotia were globoid in shape, 1$\sim$3 mm in size and white to brown in color, The optimum temperature and sclerotia on PDA was 30$^{\circ}C$ and the hyphal width was $3{\sim}10{\mu]m$. The typical clamp connections were observed in the hyphae of the fungus grown on PDA. Pathogenicity of the causal organism was proved on D. sessile according to Koch's postulate. On the basis of mycological characteristics and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report on the stem rot of D. sessile caused by S. rolfsii in Korea.

Development of a Total Internal Reflection Fluorescence (TIRF) Microscopy for Precise Imaging the Drying Pattern of a Sessile Droplet (고착 액적 증발면의 정밀 관측을 위한 전반사 형광 현미경 기법 개발)

  • Wonho Cho;Jinkee Lee
    • Journal of the Korean Society of Visualization
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    • v.21 no.3
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    • pp.65-74
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    • 2023
  • Compared to epifluorescence(EPI) microscopy which captures fluorescence from the entire depth of sample, total internal reflection fluorescence(TIRF) can selectively visualize only a single surface of it. TIRF uses a thin evanescent field generated by the total internal reflection of laser light on surface. However, conventional TIRF system are designed for total internal reflection to occur at the upper surface of sample, making them unsuitable for sessile droplet imaging. We designed a TIRF system suitable for a sessile droplet imaging by utilizing slide glass as a lightguide. We presented the details for constructing the TIRF system using a prism, slide glass, air slit, and optical trap. Then, we compared the TIRF with EPI by imaging the droplet with fluorescent particles during its drying process. As a result, TIRF allows us to distinctly visualize the drying pattern on the bottom surface of droplet.

The Effect of Tension and Drop Height on Contact Angle of Droplet on Flexible Substrate in Roll-to-Roll Systems (롤투롤 시스템에서 플렉시블 소재에 인가된 장력과 분사 높이가 액적 접촉각에 미치는 영향)

  • Kim, Dongguk;Lee, Changwoo
    • Journal of the Korean Society for Precision Engineering
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    • v.34 no.3
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    • pp.167-172
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    • 2017
  • This study proposes a method for identifying correlations between tension and drop height for sessile droplets in a roll-to-roll processing system. The effect of tension and drop height on the contact angle of a sessile droplet is presented. Design of experiment (DOE) methodology and statistical analysis are used to define a correlation between the process parameters. The contact angle is decreased while increasing tension and drop height. The influence of the tension is less significant on the contact angle compared with the effect of the drop height. However, tension should be considered as a major parameter because it is not easy to fix with roll eccentricity and compensating speed of the driven roll. The results of this study show that the effect of tension on the contact angle of a sessile droplet is more important than drop height because the drop height is fixed when the process systems are determined.

Recruitment patterns of sessile organisms on the artificial PVC panels in Jangmok Bay, southern coast of Korea (남해 장목만 부착생물의 PVC 인공부착판에서의 가입양상)

  • Choi, Jin-Woo;Park, So-Hyun;Seo, Jin-Young
    • The Korean Journal of Malacology
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    • v.27 no.1
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    • pp.29-33
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    • 2011
  • This study was conducted to investigate the recruitment pattern of sessile organisms on the artificial substrates of PVC in Jangmok Bay, Geoje Island, southern coast of Korea. Five PVC plates were submerged from March to October, 2007 at one month interval, and two plates were retrieved after one month. The dominant recruiters were a green algae, Entermorpha prolifera in March, Mytilus galloprovincialis in April, M. galloprovincialis and Styela plicata in May, S. plicata and Bugula sp. in June. During August, Balanus amphtrite and anthozoans were dominant recruiters, and a serpulid worm, Hydroides ezoensis in October. There was a clear specific recruiting period of sessile faunas depending on their reproduction cycles in a sheltered embayment like Jangmok Bay.

First Report of an Unrecorded Nematode-Trapping Fungus Species Monacrosporium phymatopagum in Korea

  • Wu, Hai-Yan;Kim, Dong-Geun
    • The Plant Pathology Journal
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    • v.26 no.3
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    • pp.264-266
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    • 2010
  • A fungus that can capture nematodes by means of sessile adhesive knobs was isolated from rotten wood in Uiseong, Korea. It was found to produce single, spindle-shaped, 3-4 septate (commonly 4-septate) conidia, $44.8\;{\mu}m$ (range, $41.6-50.1\;{\mu}m$) long and $13.3\;{\mu}m$ (range, $10.7-15.4\;{\mu}m$) wide. Conidiophores were found to be hyaline, erect, straight, and $202.7-245.7\;{\mu}m$ high. On the basis of these morphological features, the fungus was identified as Monacrosporium phymatopagum. This is the first report of M. phymatopagum in Korea which can be a potential biological control resource of plant parasitic nematode.

Evaporative Heat Transfer Characteristics of Droplet on Oxi-nitriding Surface (산질화 표면에서 액적의 증발열전달 특성)

  • Kim, Dae Yun;Lee, Seong Hyuk
    • Journal of ILASS-Korea
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    • v.21 no.1
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    • pp.53-57
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    • 2016
  • The present study aims to experimentally investigate the evaporative heat transfer characteristics of Oxi-nitriding SPCC surface. Moreover, the heat transfer coefficient was examined with respect to surface temperature during droplet evaporation. In fact, the nitriding surface showed significant enhancement for anticorrosion performance compared to bare SPCC surface but the thermal resistance also increased due to the formation of compound layer. From the experimental results, the evaporative behavior of sessile droplet on nitriding surface showed similar tendency with the bare surface. Total evaporation time of sessile droplet on the nitriding surface was delayed less than 5%. The difference in heat transfer coefficient increased with the surface temperature, and the maximum difference was estimated to be around 11% at $80^{\circ}C$ surface. Thus, this nitriding surface treatment method could be useful for seawater heat exchanger industries.