• Title/Summary/Keyword: in situ and ex situ

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Tribological Characteristics of Conditioning Methods on Polishing Pad (컨디셔닝 방식에 따른 패드의 트라이볼로지적 특성)

  • Lee, Hyun-Seop;Park, Boum-Young;Seo, Heon-Deok;Jeong, Hae-Do
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.11a
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    • pp.358-359
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    • 2005
  • Chemical mechanical polishing(CMP) process depends on a variety of variables. Especially, surface roughness of pad plays a key role in material removal in CMP in terms of transportation ability of pores and real contact area. The surface roughness is deteriorated with polishing time by applied pressure and relative velocity. In this reason, diamond conditioner has been used to maintain the roughness on the pad. The authors try to investigate the correlation between pad roughness and frictional behavior by comparing ex-situ conditioning with in-situ conditioning.

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Perspectives on the new National Ecological Institute in South Korea

  • Crane, Peter R.;Choe, Jae-C.
    • Journal of Ecology and Environment
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    • v.33 no.4
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    • pp.271-274
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    • 2010
  • The Ministry of Environment of South Korea has launched its plan to establish the National Ecological Institute. An International Symposium and Workshop was held at Ewha Womans University in Seoul on Thursday, 30 September 2010, to strengthen international cooperation, networking and partnerships for the conservation of biodiversity. This symposium was attended by experts of many major institutions for biodiversity conservation from South Korea and overseas. At the symposium and workshop preceded by a keynote speech by the renowned primatologist and conservation biologist Jane Goodall the participants discussed a wide range of topics including "biodiversity conservation: in situ and ex situ approaches", "conservation of species diversity and ecosystem management", and "international cooperation for biodiversity conservation and research". As a basis for future discussions, this article summarizes how the National Ecological Institute might contribute most effectively to public life and environmental management in South Korea and worldwide. It addresses the following issues: governance and funding, synergies within Korea, participation in international networks, external advice, a broad view of ecological issues, research agenda, building on identity, public outreach, and training the next generation of scientists.

Ex-situ 7Li MAS NMR Study of Olivine Structured Material for Cathode of Lithium Ion Battery

  • Lee, Youngil;An, JiEun;Park, Seul-A;Song, HyeYeong
    • Journal of the Korean Magnetic Resonance Society
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    • v.18 no.2
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    • pp.63-68
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    • 2014
  • $^7Li$ nuclear magnetic resonance (NMR) spectra have been observed for $LiMPO_4$ (M = Fe, Mn) samples, as a promising cathode material of lithium ion battery. Observed $^7Li$ shifts of $LiFe_{1-x}Mn_xPO_4$ (x = 0, 0.6, 0.8, and 1) synthesized with solid-state reaction are compared with calculated $^7Li$ shift ranges based on the supertranferred hyperfine interaction of Li-O-M. Ex situ $^7Li$ NMR study of $LiFe_{0.4}Mn_{0.6}PO_4$ in different cut-off voltage for the first charge process is also performed to understand the relationship between $^7Li$ chemical shift and oxidation state of metals affected by delithiation process. The increment of oxidation state for metals makes to downfield shift of $^7Li$ by influencing the supertranferred hyperfine interaction.

Mating behavior of the Mongolian racerunner (Eremias argus; Lacertidae, Reptilia)

  • Kim, Bin-Na;Kim, Ja-Kyeong;Park, Dae-Sik
    • Animal cells and systems
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    • v.16 no.4
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    • pp.337-342
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    • 2012
  • Information about the mating behaviors of an endangered species is critical for the understanding of the natural history of the species as well as in situ and ex situ breeding programs designed to rehabilitate field populations. We describe the mating behaviors of the Mongolian racerunner (Eremias argus), an endangered species in South Korea. The mating of this species consists of precopulatory, copulatory, and postcopulatory stages and is composed of 12 different mating behaviors. During the postcopulatory stage, other males or females not involved in mating show more interference behaviors than during the precopulatory and copulatory stages. The male E. argus has an extraordinarily long postcopulatory bite, which may function as a type of mate-guarding behavior. This study is the first report on the mating behavior of a South Korean reptile.

Study of Incipient Soot Particles with Measuring Methodologies (입자 측정방법을 통한 초기 수트입자 연구)

  • Lee Eui Ju
    • Journal of the Korean Society of Visualization
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    • v.2 no.1
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    • pp.12-17
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    • 2004
  • The physical characteristics of soot near the soot inception point were investigated with various measurements. In-situ measurements of particle size and volume fraction were introduced based on time resolved laser-induced incandescence (TIRE-LII) and laser-induced ion mobility (LIIM). The one has more convenience and accuracy than conventional LII technique and the other works best for particle sizes of a few nanometers at high concentrations in a uniform concentration field. A complementary ex-situ measurement of particle size is nano differential mobility analyzer (Nano-DMA), which recently developed for measuring particle sizes between 2nm and 100nm and provides high-resolution size information for early soot. Particles will be also collected on transmission electron microscope (TEM) grids using rapid thermophoretic sampling and analyzed for morphology. These measurements will allow fresh and original insight into the characterizing soot inception process. The measured physical properties of incipient soot will clarify the controlling growth mechanism combined with chemical ones, and the dominant mechanism for soot modeling can be deduced from the information.

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유류오염토양 복원을 위한 설계인자 선정에 관한 연구

  • 조장환;전권호;서창일;박정구
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.04a
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    • pp.293-296
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    • 2004
  • The objective of this study was to decide the designing factor for remediaton of the contaminated site. The soil and ground-water samples were analyzed and hydro- geological characteristics was assayed for the survey of pollution level. Also air-permeability test and MPN(most probable number) test were conducted for selecting the designing factor. The contaminants were mainly found in north-west part of the site and were expected to move toward the south. Ex-situ technology was expected more useful than in-situ one with the results of air-permeability test saying that air permeability was relatively low. Additional microbes were expected for remediation efficiency because residual microbes were loosely populated. The choosing of the designing factor was requisite for remediation of contaminated site.

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Effect of grain size of Pb(La,Ti)O$_3$thin films grown by pulsed laser deposition for memory device application (메모리 소자 응용을 위한 펄스 레이저 증착법으로 제작된 PLT박막의 열처리 효과 연구)

  • 허창회;심경석;이상렬
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.07a
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    • pp.861-864
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    • 2000
  • Ferroelectric thin film capacitors with high dielectric constant are important for the application of memory devices. In this work, thin films of PLT(28)(Pb$\sub$0.72/La$\sub$0.28/Ti$\sub$0.93/O$_3$) were fabricated on Pt/Ti/SiO$_2$/Si substrates in-situ annealing and ex-situ annealing have been compared depending on the annealing time. We have systematically investigated the variation of grain sizes depending on the condition of post-annealing and the variation of deposition rate. C-V measurement, ferroelectric properties, leakage current and SEM were performed to investigate the electrical properties and the microstructural properties of Pb(La,Ti)O$_3$.

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Real time control of the growth of Ge-Sb-Te multi-layer film as an optical recording media using in-situ ellipsometry (In-situ ellipsometry를 사용한 광기록매체용 Ge-Sb-Te 다층박막성장의 실시간 제어)

  • 김종혁;이학철;김상준;김상열;안성혁;원영희
    • Korean Journal of Optics and Photonics
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    • v.13 no.3
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    • pp.215-222
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    • 2002
  • Using an in-situ ellipsometer, we monitored the growth curve of optical recording media in real time. For confirmation of the thickness control using in-situ ellipsometry, we analyzed the deposited multi-layer sample made of Ge-Sb-Te alloy film and ZnS-Si0$_2$ dielectric films using an exsitu spectroscopic ellipsometer. The target material in the first sputtering gun is ZnS-SiO$_2$ as the protecting dielectric layer and that in the second gun is Ge$_2$sb$_2$Te$_{5}$ as the receding layer. While depositing ZnS-SiO$_2$, Ge$_2$Sb$_2$Te$_{5}$ and ZnS-SiO$_2$ films on c-Si substrate in sequence, we measured Ψ $\Delta$ in real time. Utilizing the complex refractive indices of Ge$_2$Sb$_2$Te$_{5}$ and ZnS-SiO$_2$ obtained from the analysis of spectroscopic ellipsometry data, the evolution of ellipsometric constants Ψ, $\Delta$ with thickness is calculated. By comparing the calculated evolution curve of ellipsometric constants with the measured one, and by analyzing the effect of density variation of the Ge$_2$Sb$_2$Te$_{5}$ recording layer on ellipsometric constants with thickness, we precisely monitored the growth rate of the Ge-Sb-Te multilayer and controlled the growth process. The deviation of the real thicknesses of Ge-Sb-Te multilayer obtained under the strict monitoring is post confirmed to be less than 1.5% from the target structure of ZnS-SiO$_2$(1400 $\AA$)IGST(200 $\AA$)$\mid$ZnS-SiO$_2$(200$\AA$).(200$\AA$).

Formation and Interface Mophologies of the Epitaxial $\textrm{CoSi}_2$ Using the Chemical Oxide on Si(100) Substrate (화학적 산화막을 이용한 epitaxial $\textrm{CoSi}_2$형성과 계면구조)

  • Sin, Yeong-Cheol;Bae, Cheol-Hwi;Jeon, Hyeong-Tak
    • Korean Journal of Materials Research
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    • v.8 no.10
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    • pp.912-917
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    • 1998
  • 화학적 산화막(SiOx)이 형성된 Si(100)기판 위에 Co-silicide의 형성과 계면 형상에 관한 연구를 하였다. 화학적 산화막은 과산화수소수(H2O2)의 인위적 처리에 의해 약 2nm을 형성시켰다. 그 위에 5nm 두께의 Co 박막을 전자빔 증착기에 의해 증착시킨 후 열처리하여 Co-silicide를 형성하였다. 화학적 산화막 위에서 Co-silicide 반응기구를 알아 보기 위해 $500^{\circ}C$-$900^{\circ}C$의 온도 범위에서 ex-situ와 in-situ 열처리를 하였다. 이와같이 형성된 Co-silicide 시편의 상형성, 표면 및 계면 형상, 그리고 화학적 조성을 XRD, SEM, TEM, 그리고 AES를 이용하여 분석하였다. 분석 결과 es-situ 열처리시 $700^{\circ}C$까지 CoSi2 상은 형성되지 않았고 Co의 응집화현상이 일어났다. $800^{\circ}C$ 열처리한 경우에는 CoSI2가 형성되었고 facet 현상이 크게 나타났으며 불연속적인 grain 들이 형성되었다. In-situ 열처리한 경우에는 저온에서 ($550 ^{\circ}C$)반응하여 Co-silicide가 형성되기 시작하였으며 $600^{\circ}C$부터는 facet에 의해 박막의 특성이 나빠지기 시작했다. $550^{\circ}C$에서 Co가 화학적 산화막 층을 통해 확산하여 균질한 Co-silicide를 형성하였다. 이와같이 형성된 균질한 실리사이드 층을 이용하여 다단계(55$0^{\circ}C$-$650^{\circ}C$-$800^{\circ}C$)열처리에 의해 균질한 다결정 CoSI2의 형성이 관찰되었다.

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Ex situ Conservation of the Cypripedium gutttum SW. Seedlings from Asymbiotically Germination and Adaption on High Land in Korea (멸종위기 털복주머니란 현지 외 보전 및 고랭지 적응성 검토)

  • Joung Kwan Lee;Young Hee Kwon;Yoon Sun Huh;Hee Kyu Kim;Kyung Ok Kim;Won Il Choi;Ju Hyoung Kim;Mi Jin Jeong;Sung Won Son
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2020.08a
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    • pp.11-11
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    • 2020
  • Background : The genus Cypripediums are typically adapted to the low temperature and cold climates of the high land in Korea. The species which were reported in Korean peninsula are C.japonicum, C.macranthos, C.calceolus and C.guttatum. We had already reported the successful germination of the C.macranthos and C.guttatum. The small spotted lady's slipper orchid(C.guttatum) is most endangered plants to extinction of which population was reported less than 100 in Korea. The objective of the present research is restoration of the C.guttatum in ex situ and adaptation in high land and nursery. Methods and Results : The 350 seedlings of C.guttatum were transplanted in soil at alpine area(altitude 750m) and the nursery of Korea National Arboretum(KNA) in YangPyeong city on May 2019 and 2020 in order to verify the possibility of ex situ restoration. The sprouted ratio of the seedlings were less than 10% in the alpine area and 83% in the nursery of KNA. The reasons of the diverse survival ratio are presumed as the low moisture content in the soil and heavy shade of the alpine area. The 15 cypripedium species and 29 hybrids were also effectively adapted in the KNA rare plant garden. Conclusion : These results demonstrated the difficulties of the restoration for small spotted lady's slipper orchid in the natural habitation. From the above results, we may conclude that the critical factors of the genus Cypripedium are intensive care for the fragile seedlings during the 1st year acclimatization.

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