• Korean Journal of Materials Research
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• v.21 no.2
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• pp.78-82
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• 2011

Mono- and few-layer graphenes were grown on Ni thin films by rapid-thermal pulse chemical vapor deposition technique. In the growth steps, the exposure step for 60 s in $H_2$ (a flow rate of 10 sccm (standard cubic centimeters per minute)) atmosphere after graphene growth was specially established to improve the quality of the graphenes. The graphene films grown by exposure alone without $H_2$ showed an intensity ratio of $I_G/I_{2D}$ = 0.47, compared with a value of 0.38 in the films grown by exposure in H2 ambient. The quality of the graphenes can be improved by exposure for 60 s in $H_2$ ambient after the growth of the graphene films. The physical properties of the graphene films were investigated for the graphene films grown on various Ni film thicknesses and on 260-nm thick Ni films annealed at 500 and $700^{\circ}C$. The graphene films grown on 260-nm thick Ni films at $900^{\circ}C$ showed the lowest $I_G/I_{2D}$ ratio, resulting in the fewest layers. The graphene films grown on Ni films annealed at $700^{\circ}C$ for 2 h showed a decrease of the number of layers. The graphene films were dependent on the thickness and the grain size of the Ni films.

• Korean Chemical Engineering Research
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• v.44 no.2
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• pp.207-215
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• 2006

The characteristic floc growth of Al-based coagulants was investigated in the aspect of mixing intensity and visualization of generated flocs during coagulation and flocculation processes. Zeta potential of turbid particles in the artificial water nearly approached to zero at pH 8-9, in which TDS and conductivity were minimized. The removal rate of turbidity and phosphate was maximized at the optimal mixing intensity of rapid and slow mixing stages. After the rapid mixing stage of coagulation process, small particles ($3-5{\mu}m$) were abruptly generated, and higher mixing intensity made more numbers of flocs. With the progress of slow mixing stage, the number of small particles were decreased with the simultaneous increase of intermediate particles ($7-21{\mu}m$). The number of large particles (>$23{\mu}m$) were maximized at the lowest rapid mixing intensity of $95.1sec^{-1}$, whereas small particles (<$5{\mu}m$) were maximized at the highest rapid mixing intensity of $760.7sec^{-1}$.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1999.06a
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• pp.69-80
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• 1999

Computer simulations have played a central role in the development of out understanding of the atomic scale processes involved in crystal growth. The assumptions underlying computer modeling will be discussed and out recent work on modeling of the kinetic formation of thermodynamically unstable phases in alloys or mixtures will be reviewed. Our Monte Carlo computer simulations have reproduced the experimental results on the rapid recrystallization of laser-melted doped silicon. An analytical model for this phenomenon has been developed, and its applicability to other materials will be discussed.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.4
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• pp.365-370
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• 1999

Computer simulations have played a central role in the development of our understanding of the atomic scale processes involved in crystal growth. The assumptions underlying computer modeling will be discussed and our recent work on modeling of the kinetic formation of thermodynamically unstable phases in alloys or mixtures will be reviewed. Our Monte Carlo computer simulations have reproduced the experimental results on the rapid recrystallization of laser-melted doped silicon. An analytical model for this phenomenon has been developed, and its applicability to other materials will be discussed.

• Journal of the Korean Regional Science Association
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• v.15 no.1
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• pp.23-43
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• 1999

The strategy of regional industrial specialization is empirically evaluated by examining the relationship between regional industrial structures and economic performances. The regional industrial structure is measured by three industrial diversity indices such as ogive approach, entropy maximizing approach, and economic growth and employment instability in 12 regions is analyzed. According to the time series analysis, we found that the region with more diversified industrial structure experiences more stable in employment. Otherwise, the growth rate of the region with more simplified industrial structure is higher. Therefore, the strategy of industrial specialization is implemented in order to pursuit a rapid economic growth in the short run.

• The Journal of the Korean Society for Microbiology
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• v.9 no.1
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• pp.13-18
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• 1974

Blood is one of the most important clinical specimens for the isolation of bacteria. A rapid isolation and a high isolation rate of bacteria are very important in blood culture because bacteremic patients are mostly in grave condition. Various blood culture media which support growth of most fastidious bacteria are available commercially. However, growth of bacteria are frequently delayed because of antibacterial activity of blood. Sodium polyanethol sulfonate(Liquoid) has been reported to inactivate the antibacterial substance and disrupt phagocytic cells. The beneficial effect of SPS is well recognized in the isolation of gram-positive bacteria. However, the effect does not seem to be prominent for gram-negative bacilli isolation mainly due to the rapidity of their growth. It has been experienced with Sal. typhi that the growth is much slower than that of other gram-negative bacilli. For the rapid growth of the organism, use of bile broth has been recommended. Although Sal. typhi is the most frequently isolated organism at present, about one half of total isolates are other organisms and, in case bile broth is used, other media which support growth of these organisms should be used together. Fluid thioglycollate medium(FTM) which is always used in blood culture to isolate anaerobes is inferior to brain heart infusion(BHI) for the isolation of aerobes. This study was done to determine the effect of SPS on the isolation of Sal. typhi from blood. During the Sep. 1973 to Sep. 1974 study period, 2460 blood cultures were made from the Severance hospital patients: BHI and FTM sets 1431 specimens, BHI with SPS(0.05%) and FTM sets 396 specimens, BHI and FTM with SPS sets 359 specimens, BHI and BHI with SPS sets 274 specimens. Mean incubation time required for the macroscopic detection of growth of Sal. typhi were 3.5 days on BHI and 2.7 days on BHI with SPS. The 0.8 day difference was statistically significant. On FTM the mean incubation time was 3.8 days while it was 2.9 days on FTM with SPS. The 0.9 day difference was statistically significant. The result on BHI with and without SPS sets showed faster growth on BRI with SPS in 7 specimens and slower growth in one specimen and the remaining 12 showed growth at the same time. These specimens had mean incubation time of 3.2 days on BHI and 2.3 days on BHI with SPS. The 0.9 day difference was statistically significant. This study indicates beneficial effect of SPS for the rapid isolation of Sal. typhi from clinical blood specimens.

• Journal of Ginseng Research
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• v.7 no.2
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• pp.102-107
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• 1983

The effects of saponin, one of major components (Panax ginseng C.A. Meyer), on the growth of E. coli K-12 and the formation of siderphore was observed The following results were obtained. 1. When E. coli was grown on medium containing 1${\times}$10-5%-11${\times}$10-1% of the saponin, the rate of growth was stimulated at 10-1% of the saponin significantly compared to that of control. 2. When E. coli K-12 was grown on medium containing 1${\times}$10-1% of the saponin, the amount of siderphore was two times as much as the control. 3. The growth of E. coli was observed to be dependent on the concentration of siderophore when siderophore was added to medium. 4. The effect of saponin on the formation of siderophore in vitro was observed to reach maximum at 1${\times}$10-3% of the saponin. Such results suggest that the growth rate of E. coli K-12 could be enhanced by ginseng saponin fraction through stimulation of siderphore formation. We have described the fast growth of E. coli, K-12 and B. subtilis, rapid uptake of 14C-glucose, and high level of other metabolites such as lipids and proteins of E. coli, and B. subtilis in medium containing saponing fraction compared to that of microorganisms without saponin fraction.1∼3Such differences were claimed to be due to rapid uptake of 14C-glucose by widened periplasmic region throught unknown mechanism in the prescence of saponin fraction in medium3 and have raised a question whether there is another possible factor, siderophore4(Greek for iron bears), since microorganisms must secure a sufficient amount of iron for normal growth. These are known to be synthesized by the cells under iron-deficient condition and in most case, excreted into the medium5, where they can complex and solubilize any iron present there. It is generally believed that these complexes are then taken into the cells presumably by specific transport systems, thus providing iron for cell metabolism. Within the group of enteric bacteria, only three species (E. coli, S. typhimurium, and A. aerogense) have, so far, been studied in a ny detail. The main iron-binding compound produced by these species is enterochelin, and its role in iron transport is now well established. And biosynthesis of enterochelin from 2, 3- dihydroxybenzoate and serine in the prescence of magnesium ions and ATP was reported6. 2, 3-dihydroxybenzoate was also shown to involve isochorismate and 2, 3-dihydro-2, 3-dihydroxybenzoate as intermediate.7∼11 The present paper deals with the effect of ginseng saponin fraction on growth, the level of enterochelin formation in vivo and the conversion of 2, 3-dihydroxybenzoate and serine into entrochelin in vitro, and entrochelin obtained on the growth in relation to possible explanation of ginseng saponin fraction on the rapid growth of E. coli, K-12.

• Journal of the Korean Catholic Hospital Association
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• v.4 no.1
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• pp.29-32
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• 1973

• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.5
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• pp.55-65
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• 2014

Radar remote sensing is appropriate for rice monitoring because the areas where this crop is cultivated are often cloudy and rainy. Especially, Synthetic Aperture Radar (SAR) can acquire remote sensing information with a high temporal resolution in tropical and subtropical regions due to its all-weather capability. This paper analyzes the relationships between backscattering coefficients of rice measured by RADARSAT-2 SAR and growth parameters during a rice growth period. And we applied the relationships to crop monitoring of paddy rice in North Korea. As a result, plant height and Leaf Area Index (LAI) increased until Day Of Year (DOY) 234 and then decreased, while fresh weight and dry weight increased until DOY 253. Correlation coefficients revealed that Horizontal transmit and Horizontal receive polarization (HH)-polarization backscattering coefficients were correlated highly with plant height (r=0.95), fresh weight (r=0.92), vegetation water content (r=0.91), LAI (r=0.90), and dry weight (r=0.89). Based on the observed relationships between backscattering coefficients and variables of cultivation, prediction equations were developed using the HH-polarization backscattering coefficients. Concerning the evaluation for the applicability of the LAI distribution from RADARSAT-2, the LAI statistic was evaluated in comparison with LAI distribution from RapidEye image. And LAI distributions in Pyongyang were presented to show spatial variability for unaccessible areas.

• Clinical and Experimental Pediatrics
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• v.52 no.2
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• pp.152-158
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• 2009

Reduced fetal growth is independently associated with increased risk of health problems in later life, particularly type 2 diabetes and cardiovascular diseases. Insulin resistance appears to be a key component underlying these metabolic complications. It is suggested that detrimental fetal environment may program insulin resistance syndrome. An insulin-resistant genotype may also result in both low birth weight and insulin resistance syndrome, and it is likely that the association of low birth weight with insulin resistance is the result of both genetic and environmental factors. Early postnatal rapid catch-up growth is closely related to risk for subsequent metabolic diseases. Fat mass is strikingly reduced in neonates born small for gestational age (SGA), and recent data suggest that insulin resistance seen in catch-up growth is related to the disproportionate catch-up in fat mass compared with lean mass. Endocrine disturbances are also recognized in SGA children, but overt clinical problems are infrequent in childhood. Cognitive impairment is reported in some children born SGA, especially those who do not show catch-up growth, in whom early neurodevelopmental evaluation is required. Breast feeding, also known to be protective against the long-term risk of obesity, may prevent some intellectual impairment in SGA children. Calorie-dense feeding does not seem to be appropriate in SGA infants. We must balance the positive effect of nutrition on neural development against rapid fat deposition and the future risk of insulin resistance.