• Applied Science and Convergence Technology
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• 제24권6호
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• pp.273-277
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• 2015

We investigated secondary electron emission characteristics of ZnO thin films prepared by pulsed laser deposition method with respect to the ambient oxygen pressure and the substrate temperature during the deposition. X-ray diffraction, UV-Vis spectrometry, atomic force microscopy, and ${\gamma}$-FIB were used to examine the structural, optical transmission, surface morphology, and secondary electron emission properties of the films, respectively. The secondary electron emission coefficient of the ZnO films increases as the O/Zn ratio of the films increases which was thought to result from either the ambient oxygen pressure increase or the substrate temperature decrease and as the grain size of the films decreases. It was confirmed that ZnO has better secondary electron emission characteristics than those of MgO, which is currently widely used as a material for PDP protecting layers.

• 환경영향평가
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• 제12권1호
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• pp.1-8
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• 2003

The Master Plan of Natural Environment Conservation in Korea by Ministry of Environment has been carried out since 1986. The 2nd 10-year survey started in 1997, and there are three major parts in the Master Plan : First, the basic natural environment survey, second, sites in special features of ecological characteristics such as uninhabitable islands, wetlands, etc, and third, biological species featuring status of habitat, and population dynamics. However the information in the Master Plan is very fragmented and collected data are not so abundant due to insufficient man-power and unsynchronized survey time/season. In this regard this paper examined the similar National Biological Survey in USA and compared the differences with the Master Plan in Korea. The Master Plan in Korea should separate the management zone based on hydrological characteristics, and in each zone we should set a management goal in the long term basis. Secondly the species list is not so meaningful that we must concentrate more on research activities. In each taxonomical group we set up hypotheses and research goals. Thirdly local residents and communities should be involved in research so that enhanced biological diversity should benefit people in areas. Lastly legislation and laws should be reexamined and rectified to provide information to the managers that deals with natural resources, expecially when conflicting with economic matters.

• Journal of Species Research
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• 제11권4호
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• pp.310-320
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• 2022

As a subset study to discover indigenous prokaryotic species in Korea, we isolated 20 bacterial strains and assigned them to the phyla Actinobacteria, Bacteroidota, Firmicutes, and Proteobacteria. From the high 16S rRNA gene sequence similarity (≥98.7%) and formation of a robust phylogenetic clades, we determined that each strain belonged to independent, predefined bacterial species. There are no official reports of these 20 species in Korea; therefore, 7 strains of the Actinobacteria, 2 strain of the Bacteroidota, 3 strains of the Firmicutes, and 8 strains of the Firmicutes are described in Korea for the first time. Gram reaction, colony and cell morphology, basic biochemical characteristics, and isolation sources are also described in the species description section.

• Mycobiology
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• 제42권2호
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• pp.109-113
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• 2014

During a survey of marine fungi from the waters surrounding Jeju Island, Korea, several Penicillium strains were isolated from seawater and marine sponges. Based on morphological characteristics and phylogenetic analyses of the internal transcribed spacer and RNA polymerase subunit II, four strains were identified as Penicillium antarcticum, a fungus that, to the best of our knowledge, had not been previously reported in Korea. Here, we provide detailed descriptions of the morphological characteristics and extracellular enzyme activities of the four strains.

• 한국군사과학기술학회지
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• 제7권3호
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• pp.110-121
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• 2004

Pyrolysis-mass spectrometry, incorporating an in situ thermal hydrolysis and methylation(THM) step, has been used to study biological materials for bacteria, toxin and virus. Newly developed pyrolyzer was used to decompose biological materials, and tetramethylammonium hydroxide(TMAH) was used as a methylation reagent. Chemical ionization(CI) using ethanol and ion trap mass spectrometer(ITMS) were used to ionize and analyze of pyrolysis components, respectively. Analytical characteristics of bacteria (including spore), virus and toxin were analyzed. Also acquisition and interpretation of mass spectra as biomarkers for classification/identification of biological material s were explained.

• 한국균학회지
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• 제44권4호
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• pp.263-270
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• 2016

Freshwater is a diverse and complex environment for fungi and provides several types of habitat including plant litter, sediment, and carcasses. We collected plant litter from the main stream and branch streams of Nakdong River, Sohancheon in Samcheok, and Geumoreum in Jeju. From several samples of plant litter, we isolated 8 fungal strains belonging to 4 Montagnulaceae species unrecorded in Korea: Paraconiothyrium archidendri, Paraphaeosphaeria sporulosa, Paraphaeosphaeria michotii, and Paraphaeosphaeria viridescens. These fungi were identified by phylogenetic analysis using the internal transcribed spacer (ITS) region and examination of morphological characteristics. Montagnulaceae is known as one of the families in Pleosporales and includes coniothyrium-like fungi. In this study, we described phylogenetic analysis and mycological characteristics of these species, and this is the first report of these taxa in Korea.

• Journal of Species Research
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• 제5권3호
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• pp.309-312
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• 2016

Cleantioides rotundata (Kussakin, 1982) is reported for the first time in South Korea. Specimens of C. rotundata were collected with a small hand net from the intertidal zone of Opo-ri, Yeongdeok-gun in South Korea. This species makes tubes using seagrass debris at our sampling location and distinguished by the following characteristics: pleotelson long, length almost 1.6 times as long as width; dorsum of distal one third with deeply bilobed depression on plane. In this paper, we provide descriptions of diagnostic characteristics and illustrations of morphology of C. rotundata. Additionally, a key to the Korean species of the genus Cleantioides is provided and the partial sequences of the mitochondrial cytochrome c oxidase subunit 1 (CO1) are provided as molecular characteristics.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.178.2-178.2
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• 2013

Conventional ultraviolets A,B,C are known to be very important factor of killing, changing surface properties of biological cells and materials. It is of great importance to investigate the influence of extreme ultraviolet (EUV) exposure on the biological cell. Here we have studied high density EUV plasma and its emission characteristics, which have been generated by plasma focus device with hypercycloidal pinch (HCP) electrode under various Ar gas pressures ranged from 30~500 mTorr in this experiment. We have also measured the plasma characteristics generated from the HCP plasma focus device such as electron temperature by the Boltzman plot, plasma density by the Stark broading method, discharge images by open-shuttered pin hole camera, and EUV emission signals by using the photodiode AXUV-100 Zr/C.

• 한국응용곤충학회:학술대회논문집
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• 한국응용곤충학회 2001년도 합동 춘계 학술발표회
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• pp.100-100
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• 2001

• 한국응용곤충학회:학술대회논문집
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• 한국응용곤충학회 2002년도 추계 합동 특강 및 학술발표대회
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• pp.106-106
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• 2002