• Mycobiology
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• 제36권3호
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• pp.143-147
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• 2008

We have detected the slime mold, Diachea leucopodia (GNU06-10) in a strawberry greenhouse located in Sancheong-gun, Gyeongnam. Typical fruiting bodies had developed gregariously on the strawberry leaves, petioles, and plant debris on ground soil habitat, and also surprisingly on plastic pipes and a vinyl covering. Field samples were examined via stereomicroscopy, light microscopy, and SEM for the determination of morphological characteristics. Dark-brown to black spores formed gregariously within the stipitate cylindrical sporangium, and were covered by an iridescent peridium, which may be intact at maturity, or may have disintegrated. The upper portion of the peridium generally breaks up to expose the spores, whereas the lower portion was usually persistent. The results of energy dispersive X-ray spectrometer (EDS) analysis showed that lime was present in the stalk and columella but absent from the spores, capillitium, and peridium. The above characteristics confirm its taxonomic position in the genus Diachea. However, this genus is intermediate in character between the Physarales and Stemonitales of the Myxogastromycetidae. Hence, this genus had been classified as a member of the Stemonitales until the mid-1970's, on the basis of its iridescent peridium and noncalcareous capillitial system, similar to Comatricha of the Stemonitaceae. By way of contrast, emphasis on morphological characteristics, most notably the calcareous stalk and typical columella, places Diachea within the order Physarales. The presence of a phaneroplasmodium during the trophic stage and lime deposition in its sporophores, as was confirmed in this work, supported the inclusion of Diachea in the Physarales, and the noncalcareous capillitial system verified its identification as a member of the Didymiaceae. Further characteristics of the species D. leucopodia include the following: phaneroplasmodium, spore globose 7.5 ${\mu}m$ in diameter, very minutely roughened; sporangia $500{\mu}m\times1mm$, more or less cylindrical, gregarious, stalked 1.2mm; stalk and columella white.

• KCI Concrete Journal
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• 제11권3호
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• pp.127-140
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• 1999

In this paper, a microscopic analysis of prefinitelv strained cement paste specimen was carried out. The microscopic behavior of concrete under triaxial stress must be fully understood in order to explain the additional ductilitv that comes from lateral confinement and to get microstructural information in large deformed and large strained concrete. The so-called "tube-squash" test was applied to achieve enormously high shear and deviatoric strain of concrete under extremly high pressure without fracture. Then, microscopic analyses by focusing on hydration and microstructure of Prefinitely strained cement paste were carried out on cored-out deformed and virgin (undeformed) cement paste specimens : the first specimen being 40 days old, the second one being one year old. The microscopic analysis bv Field Emission Scanning Electronic Microscope (FESEM) was carried out for comparison between the specimens after 40 days and those arter one year. For one year old specimens, X-Ray Diffractometer (XRD) analysis, Energy Dispersive x-rav Spectrometer (EDS) analysis, and Differential Thermal Analysis/Thermo-Gravitv (DTA/TG) analysis were also carried out to study the hydration and the microstructures of prefinitely strained cement paste specimen by focusing on the methodologies of their microscopic analyses. analyses.

• 한국안전학회지
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• 제18권1호
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• pp.89-93
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• 2003

The failure of rock slopes were influenced by weathering, which causes change in the shear strength. The weathering is also directly related to slaking and swelling characteristics. In the paper, the core of diameter loom was obtained by digging on rock slope of Kong-ju in Korea and then EDX(Energy Dispersive X-ray spectrometer) analysis was carried out to verified element of chief rock-forming minerals. Uniaxial compression tests, slaking tests, and point load test are performed to study engineering characteristics of conglomerate and red shale. As a results of slaking test, slaking index of conglomerate indicate range of 85.11-99.58 and shale indicate 58.37-99.23. Therefore, it is recognized that the resistance of shale to weathering decreases in shallow depth and it greatly influences the strength of rock. The result of uniaxial compression test and Point load test show that the strength of sedimentary such as conglomerate and red shale has an influence on both weathering and saturation.

• 한국주조공학회지
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• 제19권6호
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• pp.466-471
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• 1999

To investigate inclusions(oxides) which cause some trouble in the quality of the metal and a steel-making process, samples were manufactured. The molten irons were deoxidized using Al deoxidizer, and the morphology of the deoxidation products and the process of deoxidation were investigated by optical microscope, scanning electron microscope (SEM) and energy dispersive X-ray spectrometer(EDS). The reactions between Fe melt and Al deoxidizer formed deoxidation product, and those reaction may accelerates the reduction of oxide in Fe melt. According to the results of SEM analysis after deoxidizing treatment, it was found that deoxidation products had spherical cluster shape when 1% Al was added and dendritic shape with $2{\sim}3%$ A1 addition. The deoxidation products were globular, dendritic, polygonal(square) and cluster shape.

• 한국항만학회지
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• 제12권2호
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• pp.323-328
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• 1998

A quartz crystal analyzer is utilized to monitor the corrosion process of an aluminum surface of a quartz crystal for marine sensor by sea water. A quartz crystal having 2000 $\AA$ of aluminum layer is installed in a specially designed cell and is in contact with sea water imitated electrolyte solution. While a constant potential is applied to the cell, the resonant frequency and resonant resistance are simultaneously measured using the quartz crystal analyzer. In addition, surface topographs are taken with an atomic force microscope(AFM) and the element analysis of the surface is conducted using an energy dispersive X-ray spectrometer(EDX). The simultaneous measurement of resonant frequency and resonant resistance during the corrosion process explains the change of surface structure caused by the corrosion. The variation of resonant frequency addresses the amount surface metal dissolution. As a conclusion, it is found that a simple measurement using the quartz crystal analyzer can replace the complex monitoring employing large equipments in the investigation of a corrosion process of sensor surface.

• 한국환경과학회지
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• 제30권3호
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• pp.279-287
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• 2021

In this study, the composition and morphology of deposited dust particles with size ranging from a few to tens ㎛ were investigated using SEM/EDX (scanning electron microscopy with energy dispersive x-ray spectrometer). Then deposited dust particles were classified into 8 groups: quartz, aluminosilicates, ca-rich, Fe/Ti oxide, carbon-rich, industrial particle, Fe-rich, and biogenic particle. The sources of deposited dust were high in the order of aluminosilicates 41% > biogenic 18% > Fe-rich 11% > quartz and C-rich 8% > industrial 7% > Fe/Ti oxide 5% > Ca-rich 1%. In particular, the ratio of biogenic particles was relatively high due to influence of pollen. The ratio of carbon-rich was 11% at YM site, 10% at MD site, and 4% at MO site, and the site close to the large emission source was high.

• 한국산학기술학회논문지
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• 제21권10호
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• pp.30-39
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• 2020

본 연구에서는 Sol-Gel 방법을 이용하여 단일상의 Barium ferrite 분말을 제조하였으며, 이때 Ba에 대한 Fe(Fe/Ba)의 몰비와 열처리 온도를 달리하여 단일상의 Barium ferrite를 제조하기 위한 최적의 실험조건을 찾고자 하였다. 또한 고밀도 자기기록매체에 사용되기 위한 2.5 ~ 5.5 kOe 크기의 보자력을 가지는 ferrite 미립자 제조를 위해 보자력 제어에 뛰어난 효과를 지닌 cobalt를 첨가제로 하여 cobalt가 치환된 Barium ferrite 미립자를 제조하고 이들에 대한 자기적 특성 변화를 조사하였다. 제조된 Barium ferrite의 결정구조 및 단일상의 합성여부를 확인하기 위해 X-Ray Diffractometer(XRD), Thermogravimetric-Differential Thermal Analysis(TG-DTA), Field Emission Scanning Electron Microscope(FE-SEM)을 이용하여 분석하였으며, 화학적 구조와 조성의 분석을 위해 Fourier Transform Infrared Spectroscopy(FT-IR), Energy Dispersive X-Ray Spectrometer(EDS)를 사용하였다. 또한 Vibrating Sample Magnetometer(VSM)을 통해 cobalt가 치환된 Barium ferrite 분말의 보자력을 측정하였다. 그 결과 단일상의 Barium ferrite는 Fe/Ba의 몰비가 10, 900 ℃의 열처리 온도에서 가장 잘 합성되었다. Co의 첨가량이 증가할수록 보자력은 감소하였으며 Fe에 대한 Co(Co/Fe)의 몰비가 0.16 이내 일 때, 고밀도 자기기록매체에 사용할 수 있는 보자력 값인 2.5 ~ 5.5 kOe를 가지는 Barium ferrite가 합성되었다.

• 한국전기전자재료학회논문지
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• 제29권2호
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• pp.95-100
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• 2016

We fabricated a tin sulfide (SnS) layer with Sn/Mo/glass layers followed by a RTP (rapid thermal processing), and studied the film growth and structural characteristics as a function of annealing temperature and time. The elemental sulfur (S) was cracked thermally and applied to form SnS polycrystalline film out of the Sn percursor at pre-determined pressures in the RTP tube. The sulfurization was done at the temperature from $200^{\circ}C$ to $500^{\circ}C$ for a time period of 10 to 40 min. At ${\leq}300^{\circ}C$, 20 min., p-type SnS thin films was grown and showed the best composition of at.% of [S]/[Sn] $${\sim_=}$$ 1 and [111] preferred orientation as investigated from using XRD (X-ray diffraction) analysis and EDS (energy dispersive spectroscopy) and SEM (scanning electron microscopy), and optical absorption by a UV-VIS spectrometer. In this paper, we report the details of growth characteristics of single phase SnS thin film as a function of annealing temperature and time associated with the pressure and ambient gas in the RTP tube.

• 분석과학
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• 제15권6호
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• pp.567-573
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• 2002

국내에서 석탄을 이용하는 발전소에서 발생되는 비산회의 최대 재활용처는 콘크리트 혼화제로의 사용인데, 여기에 사용되는 비산회에 미연탄소분이 많게되면, 탄소분에 의한 콘크리트의 질 저하가 유발된다. 현재 콘크리트 혼화제로 공급되고 있는 비산회는 미연탄소분의 함량을 낮추기 위해 정제과정을 거치고 있다. 이 과정에서 발생되는 부산물인 미연탄소분은 폐기물로서 전량 매립되고 있다. 본 연구에서는 비산회로부터 부선법으로 미연탄소분을 추출 정제하고, 이 미연탄소분을 재활용하기 위한 기초 연구의 하나로 탄소분의 형태와 모양을 조사하였다. 탄소분의 형태와 탄소분에 함유된 회분의 화학적 조성특성은 주사 전자현미경과 이에 부착되어 있는 에너지 분산형 X-선 형광분석기를 이용하여 파악하였다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권1호
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• pp.8-12
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• 2000

The properties variation by deterioration of the 600V grade heat-resistant polyvinyl chloride insulated wire(HIV) was analyzed. The weight variation of the thermal deteriorated HIV was about 42% at 80$0^{\circ}C$ and over. From the analysis result of the metallurgical microscope photographs it shows that the sorface of normal wire showed the elongated structures. However the elongated structures did not appear at $900^{\circ} and over and we could observe that particles were grown. The grown oxidized substances in the thermally deteriorated electric wire were observed by SEM. The CuL, CuK, $CuK_b$, OK and CIK spectra of the thermally deteriorated HIV at $300^{\circ}C$ were uniform regardless of the scanning length, but the spectra of CIK could not found at above $700^{\circ}. At the DTA analysis, the endothermic reactions were occurred around $3006{\circ}C\; and\; 400^{\circ}C$ and the exothermic reactions were occurred around $470^{\circ}, respectively.