• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.484-487
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• 2001

Amorphous carbon thin films were deposited using laser ablation technique on Si(100) substrates at different temperatures. In this study, effects of the substrate temperature on the properties of amorphous carbor, films were systematically investigated. The surface morphologic and structural properties of the films were studied by scanning electron microscopy (SEM) and raman spectroscope, respectively. With increasing of the substrate temperature, the surface morphologies were changed significantly. Moreover the intensity ratio of D-band and G-band and the full width at half maximum of these bands were dependent on substrate temperatures.

• Applied Microscopy
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• v.27 no.4
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• pp.453-460
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• 1997

The tissue types of stromata were observed intensively in four species of Hypoxylon under a scanning electron microscope (SEM). These stromata were sectioned with a freezing fracture method for observation. Several tissue types were recognized and stable in each species. This study presents the most intensive observation of tissue types of each layer of stromata. It will be useful for taxonomic criteria for the species level. However, the tissue types can not be major taxonomical criteria for the genus Hypoxylon.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.484-487
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• 2001

Amorphous carbon thin films were deposited using laser ablation technique on Si(100) substrates at different temperatures. In this study, effects of the substrate temperature on the properties of amorphous carbon films were systematically investigated. The surface morphologic and structural properties of the films were studied by scanning electron microscopy (SEM) and raman spectroscope, respectively. With increasing of the substrate temperature, the surface morphologies were changed singnificantly. Moreover the intensity ratio of D-band and G-band and the full width at half maximum of these bands were dependent on substrate temperatures.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.18 no.5
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• pp.455-461
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• 2009

In a scanning electron microscopy, image distortion is a critical issue and it is needed to be eliminated by some kinds of schemes. In this work, scanning frequency and scanning wave form are adjusted to have an improved image. The relationship between scan coil and its driver is investigated and appropriate frequency and wave form are suggested. It is proved that the selected frequency and wave form showed an enhanced image with less distortion, which were done by experiments. In addition, a noise elimination is addressed, providing improved image with a GROUND signal integration with the amplifier and the scan driver.

• Carbon letters
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• v.2 no.3_4
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• pp.202-211
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• 2001

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.84.1-84.1
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• 2010

Since the discovery of the carbon nanotube(CNTs), they have attracted much attention because of unique properties that may impact many fields of science and technology. The considerable properties of CNTs include high surface area, outstanding thermal, electrical conductivity and mechanical stability. However, uniform deposition of Pt nanoparticles on carbon surface remains inaccessible territory because of the inert carbon surface. In this study, we prepared directly oriented CNTs on carbon paper as a catalyst support in cathode electrode. carbon surface was functionalized using aryl diazonium salt for increasing adhesion of Ni particles which is precursor for growing CNTs. For fabricate electrode, CNTs on carbon paper were grown by chemical vapor deposition using Ni catalyst and Pt nanoparticles were deposited on CNTs oriented carbon paper by polyol method. The performance was measured using Proton electrolyte Membrane Fuel Cell(PEMFC). The structure and morphology of the Pt nanoparticles on CNTs were characterized by Scanning electron Microscopy(SEM) and Transmission electron Microscopy (TEM). The average diameter of Pt nanoparticles was 3nm.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.2
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• pp.265-270
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• 1993

Ammonia and/or sulphur dioxide treated and untreated wheat leaf sheaths were compared for cell wall digestion by incubation with rumen liquor for 24 and 48 hours. Scanning electron microscope (SEM) was used to study the relative rate and extent of cell wall digestion. Treated wheat straw leaf sheaths were distorted, with more distortion observed in ammonia and sulphur dioxide combined treatment than any other treatment. Rumen liquor digestion for 24 hours of untreated leaf sheath showed disrupted phloem, partially ruptured parenchyma and vascular tissues and further partially distorted inner bundle sheaths and vascular bundle after 48 hours incubation. Sulphurated leaf sheaths showed extensive degraded parenchyma and sclerenchyma material in 24 hours incubation, however, all tissues were irregulary shaped in 48 hours incubation. In ammoniation, epidermal cell walls and small vascular bundles began to disintegrate by 24 hours incubation, extensively changed structure and degraded epidermal tissue by 48 hours incubation. Combination treatment of leaf sheaths degraded all cell walls of parenchyma, phloem and vascular bundle by 24 hours incubation, however, structures only of inner bundles sheath with extended land, sclerenchyma and cutinized epidermal cell walls remained.

• Composites Research
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• v.28 no.1
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• pp.1-5
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• 2015

In this paper the influence of fiber orientation of basalt and carbon inter-ply fabrics on the flexural properties of hybrid composite laminates was experimentally investigated. Four types of basalt/carbon/epoxy inter-ply hybrid composite laminates with varying angle ply orientation of reinforced basalt fiber and fixed orientation of carbon fiber were fabricated using hand lay-up technique. Three point bending test was performed according to ASTM 7264. The fracture surface analysis was carried out by scanning electron microscope (SEM). The results obtained from the four laminates were compared. Lay-up pattern of $[0B/+30B/-30B/0C]_S$ exhibits the best properties in terms of flexural strength and flexural modulus. Scanning electron microscopy results on the fracture surface showed that the interfacial de-bonding between the fibers and epoxy resin is a dominant fracture mode for all fiber lay-up schemes.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.7
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• pp.1018-1021
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• 2002

The objective of this study was to investigate the villus distribution in the caeca of domestic geese based on the fine structure. The caeca of White Roman geese, 14-week old, were sampled and specimens were detected under photomicroscope and scanning electron microscope (SEM). The results indicated that the villi existed at the proximal caecum. The morphologies of these villi showed finger-like, peak-like or tongue-like shapes. The heights of the villi decreased far from the proximal caecum. No villi were found in the middle and distal caecum. It was obvious that the proximal segment was the main portion for absorbing food nutrients in the caeca. The caecal content particles were small and possessed a viscid character. The large particles filtered out at the proximal caecum just like a mesh. The surface of the middle caecum exhibited parallel ridges with no villi. There were band plicae circular shapes found in the middle caecum under scanning electron microsopy.

• Carbon letters
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• v.5 no.2
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• pp.75-80
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• 2004

The studies on activated carbon prepared from walnut shell and groundnut shell were undertaken to ascertain the effect of initial state of precursor and activation process on the development of porosity in the resulting activated carbon. Walnut shell based carbon shows the presence of cellular pores while Groundnut shell based carbon shows fibrillar pore structure. The adsorption parameters, characterization of product and scanning electron microscopic studies carried out showed the presence of mainly Micro, Meso and Macro porosity in carbon prepared from Walnut shell while mainly micro porosity was observed in Groundnut shell based activated carbon. An interrelationship between the adsorption efficiency and porosity in terms of quality control parameters, for before and after activation, was validated through the scanning electron microscopic data.