• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3711-3718
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• 2012

Here, we report a chain-length dependent morphology and pore structure tailing of mesoporous silica templated from organogels, which is formed by primary alkylamine and ethylene glycol at room temperature. As the chain length of alkylamine changes from 12 to 18, the resulted materials exhibit a morphology change from layers to spheres and platelets, respectively. SEM and TEM observation revealed that these shapes appear to be inherited from their parent organogels. Further pore structure characterization by nitrogen sorption analysis demonstrates that all the resulted silicas exhibit typical IV isotherms indicative of uniform mesopores, and their pore sizes are dependent on the chain length of alkylamine used.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권2호
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• pp.156-156
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• 2001

The objective of this study was to investigate the effects of nutrients and culture conditions on morphology during the seed culture of C. acremonium ATCC 20339 Morphological factors such as hyphal length number of tips number of arthrospores were observed to investigate the relationship between seed morphology and CPC production. During the time course of seed culture, hyphal length was shortened and the number of arthrospores increased rapidly On the other hand the number of tips deceased rapidly and this was closely related to the hyphal length Mixed nitrogen sources of 3% solybean meal and 1% cotton seed flour were determined as the proper organic nitrogen sources, in terms of the morphological factors in the seed culture. This fact was proven in batch culture for the production of Cephalosporin C. It was also found that a proper agitation speed enhanced the morphological differentiation of C. acremonium ATCC 20339, thus improving the production of Cephalosporin C.

• Journal of Information Display
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• 제2권4호
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• pp.52-56
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• 2001

This paper presents the effects of the phosphor layer morphology related to the discharge volume on the discharge and radiation characteristics of the Red, Green, and Blue cells in an AC-PDP. As the thickness of the phosphor layer increases and the corresponding discharge volume in the cells decreases, the voltage margin decreases due to an increase in the sustain voltage. In contrast, the IR(Infrared) emission, discharge current, and luminance characteristics remain almost unchanged, regardless of any changes in the phosphor layer morphology.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.324-329
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• 2004

In this study, an application of crack morphology variables in the Leak-Before-Break(LBB) evaluation for nuclear piping systems is investigated, including influences on the leakage crack size and crack instability loads. The crack surface roughness and the number of flow turns as a function of the crack opening displacement are applied to LBB evaluations for KSNP pressurizer surge line, for which fatigue and stress corrosion cracking are considered as failure mechanisms. As a result, there would be a significant impact on safety margins to acceptance criteria for the surge line if crack morphology variables are applied additionally to the current regulatory guide without re-analyses for justification of safety factors being applied on the leakage crack size and piping loads for evaluations.

• International Journal of Oral Biology
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• 제39권2호
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• pp.115-120
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• 2014

Minimal inhibitory concentration (MIC) is the lowest concentration of antibiotics that inhibits the visible growth of a microorganism. It has been reported that sub-MIC of antibiotics may result in morphological alterations along with biochemical and physiological changes in bacteria. The purpose of this study was to examine morphological changes of periodontal pathogens after treatment with sub-MIC antibiotics. Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, and Porphyromonas gingivalis were used in this study. The MIC for amoxicillin, doxycycline, metronidazole, penicillin, and tetracycline were determined by broth dilution method. The bacterial morphology was observed with bright field microscope after incubating with sub-MIC antibiotics. The length of A. actinomycetemcomitans and F. nucleatum were increased after incubation with metronidazole; penicillin and amoxicillin. P. gingivalis were increased after incubating with metronidazole and penicillin. However, F. nucleatum showed decreased length after incubation with doxycycline and tetracycline. In this study, we observed that sub-MIC antibiotics can affect the morphology of periodontal pathogens.

• 대한치과보철학회지
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• 제30권3호
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• pp.401-410
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• 1992

The purpose of this study was to investigate the dimensional changes and surface morphology of dentures processed by various polymerization conditions. The measurements were done by taking radiograph and using vernier calipers and each specimen was observed on scanning electron microscope. Results obtained were as follows. 1. The difference of dimensional stability was not recognized between various polymerization conditions(heat-cured resin, pour-type resin, microwave-cured resin, and injection molding resin). 2. There were expansion and shrinkage in the occlusal dimension, shrinkage in the frontal dimension, and expansion in the lateral dimension. 3. Scanning electron microscope pictures of heat-cured resin showed dense and regular surface morphology. 4. Microwave-cured resin surface appeared more regular and smooth than pour-type resin but less dense and more irregular than heat-cured resin. 5. Scanning electron microscope pictures of pour-type resin with the lowest dimensional change showed the most irregular surface morphology.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2000년도 제32회 추계학술대회 정기총회
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• pp.23-28
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• 2000

The determination of surface morphology is believed to be extremely important in the areas of contact mechanics, adhesion and friction. In order to describe morphology of various rubbed surface, the wear test was carried out under different experimental conditions in lubricating wear. And fractal descriptors was applied to rubbed surface of hydraulic driving material with image processing system. These descriptors to analyze surface structure are fractal dimension. Surface fractal dimension can be determined by sum of intensity difference of surface pixel. Morphology of rubbed surface can be effectively obtained by fractal dimensions.

• Journal of Plant Biology
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• 제39권4호
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• pp.237-242
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• 1996

Epidermal leaf cell phytoliths of 17 species of Oryza were examined with backscattered electron imaging with scanning electron microscopy to determine the usefulness of phytolith morphology for systematic studies. Many kinds of identifiable phytolith morphology are observed in the leaf blades of Oryza. They are different among species as well as between adaxial and abaxial surface and costal and intercostal strip portions of leaf blades. Distinguishing phytolith characters are useful at the level of the section, such as Angustifoliae, Ridleyanae, and Granulatae. The results of a cluster analysis using 21 qualitative characters of phytoliths reveal many taxonomic characteristics which are compatible with current taxonomy.

• International Journal of Naval Architecture and Ocean Engineering
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• 제11권1호
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• pp.510-520
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• 2019

To investigate the morphology characteristics of air layer in the air cavity, a numerical method with the combination of RANS equations and VOF two-phase-flow model is proposed for a plate with air cavity. Based on the model above, the dynamic and developmental process of air layer in the air cavity is studied. Numerical results indicate that the air layer in the plate's air cavity exhibits the dynamic state of morphology and the wavelength of air layer becomes larger with the increasing speed. The morphology of air layer agrees with the Froude similarity law and the formation of the air layer is not affected by the parameters of the cavity, however, the wave pattern of the air layer is influenced by the parameters of the cavity. The stable air layer under the air cavity is important for the resistance reduction for the air layer drag reduction.

• Journal of Industrial and Engineering Chemistry
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• 제67권
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• pp.92-98
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• 2018

The effect of surfactants with different chain length on the drying dynamics of nanosized dispersion droplets and on the final morphology of the grains formed after water evaporation is investigated experimentally. An acoustic levitator was used to examine the drying dynamics of single droplets and SEM imaging was used to characterise the morphology of the final dried grains. Results show that the drying of drops with high molecular weight surfactants leads to more irregular grains and that the grain morphology is related to surface tension driven instability of the evaporating droplets which may lead to formation of hollow dried grains.