• Journal of the Korean Chemical Society
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• v.28 no.2
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• pp.79-85
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• 1984

The ionic association constant(K) of 2,4,6, N-tetramethyl pyridinium iodide (TeMPI) in 95 volume percentage ethanol-water mixture were determined by a modified UV and conductance method at $25^{\circ}C$ to $50^{\circ}C$ under 1 to 2,000 bars. The K values increase with increasing pressure and have maximum value at $40^{\circ}C$. The partial molar volume hange (${\Delta}V$) has relatively small negative value and the absolute values of ${\Delta}$ are minimum at $40^{\circ}C$. The ion size parameter(a) of TeMPI have maximum value at $40^{\circ}C$. {\Delta}H^{\circ}$ values are zero, positive and negative at 40^{\circ}C$, $25^{\circ}C$ and $50^{\circ}C$ respectively. Other thermodynamic parameters such as the changes of standard entropy ({\Delta}S^{\circ}$) and free energy {\Delta}G^{\circ}$ were evaluated. From these experimental results, we came to conclusion that TeMPI is stabilized by the elevation of pressure and that of temperature below $40^{\circ}C$ but weakly dimerized at $40^{\circ}C$ because of the intermolecular hydrophobic interaction of eight methyl groups of two molecules. And it thermally decomposed above $50^{\circ}C$.

• Textile Coloration and Finishing
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• v.17 no.5 s.84
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• pp.53-60
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• 2005

Fusing press m/c is used for heating and pressing the specimens that are fed into between the two moving belts. Therefore the belt movement, belt temperature, and the pressure between belts must be kept constant. Especially, the belts should move in a limited operation range. When the belts run far out of the operation point, the machine has to be stopped, which results in a product defect because the fusing conditions, e.g., temperature and pressure, change during the transient process time period. It is important to avoid the belt stopping by maintaining the belt movement in a limited range. This study reports about the movement of the endless fusing belt in a long-span roller fusing m/c. The belt position changes as the 1st-order system does; if the roller axes are slanting each other with a certain angle, the belt running around the two rolls shows a dynamic behavior with the time that deviates fastly at the beginning from the initial condion and slows down. Then it reaches at a final position. The skewer the axes, the greater the position change. The inital change rate of the belt becomes large as the skewness of the axes between the two rollers increases.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.30 no.3
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• pp.30-38
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• 2016

In this research, a 6W white LED package with a Glass Remote Phosphor was developed to improve the life of an LED package. The Glass Remote Phosphor was fabricated by the Phosphor in Glass (PiG) method, wherein phosphor YAG:Ce was mixed with glass frit and then heat treated. A paste with 75wt.% of a phosphor substance and 25wt.% glass frit was coated on a glass substrate two times using the screen-printing technique and heat-treated at $800^{\circ}C$ ; this structure gave a luminous efficacy of 136.1lm/W, color rendering index of 74Ra, and color temperature of 5,342K, thus satisfying the requirements as a light source for lighting. Moreover, an IES LM-80 accelerated life test was conducted on the same LED package for 6,000h in order to estimate the L70 lifetime based on IES TM-21. The results showed guaranteed lifetimes of 213,000h at $55^{\circ}C$, 245,000h at $85^{\circ}C$, and 209,000h at $95^{\circ}C$.

• Applied Biological Chemistry
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• v.48 no.2
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• pp.109-114
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• 2005

A bacterium capable of emulsifying hydrocarbon, n-hexadecane, and decreasing surface tension of the culture media using oil collapsing method was isolated. The bacterium was partially identified as Bacillus sp. and named BJS-51. n-Hexadecane was the most effective carbon source for production of biosurfactant. Surface tension was decreased from 76 dyne/cm to 31 dyne/cm and CMD (critical micelle dilution) had the highest value of 5.7 at 3% n-hexadecane. Ammonium phosphate was the most effective nitrogen source, when C/N ratio was 60, surface tension and CMD were 29 dyne/cm and 9.2, respectively. Optimum pH and temperature were 7.2 and $30^{\circ}C$, respectively. Produced biosurfactant was extracted and purified using organic solvent extraction method and preparative HPLC systems. After analysis by various color reaction, this biosurfactant was identified as lipopolysaccharide. Surface tension and CMC (critical micelle concentration) of purified biosurfactant were 27 dyne/cm and 0.08 g/l, repectively. CMD was 9.2, so the yield of biosurfactant was about 0.74 g/l at the optimal conditions. The biosurfactant was very stable at wide range of $pH\;2{\sim}12$ with surface tension $29{\sim}31\;dyne/cm$ and showed $29{\sim}30\;dyne/cm$ of surface tension after heat treatment at $100^{\circ}C$ for 60 min.

• Korean Journal of Materials Research
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• v.9 no.1
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• pp.8-13
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• 1999

$ZrB _2$ was prepared from a mixture of $ZrO_2$, $B_2$$O_3$and Mg by SHS method. The combustion products were successfully obtained from a mixture of $Zro_2$:$B_2$$O_3$:Mg=1:2.0:8.5(molar ratio). MgO, by-product, was removed to 92.7% by leaching with 1M HCl solution at 9$0^{\circ}C$, for 10 hours. After leaching, the mean particle size of the resultant $ZrB_2$powders was 23.6$\mu\textrm{m}$. $ZrB_2$-ZrC composite was suitably obtained from a mixture of C/Zr=1.2 molar ratio by arc-melting method. The density of arc-melted specimen increased by adding excess zirconium content(x). The bulk density was 6.17g/㎤ for x=0, and 6.37g/㎤ x=4. Vickers hardness of arc-melted specimen was /$1290kg\textrm{mm}^2$ for x=0, and fracture toughness increased to 4.2MPa.m\ulcornerforx=4 compared to 3.4MPa.m\ulcornerfor x=0.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.555-559
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• 2012

Manures contain a variety of pathogenic microorganisms that pose a risk to human or animal. On-farm contaminations through contaminated manure were considered likely sources of the pathogen for several outbreak. Pathogenic microorganisms may survive in low numbers during the composting process and subsequently regrow to high levels under favorable conditions. The objective of this study was to investigate effect of temperature on survival of Salmonella enterica and Staphylococcus aureus in livestock manure compost. Commercial livestock manure compost (manure 60%, sawdust 40%) was inoculated with S. enterica and S. aureus. Compost was incubated at four different temperatures (10, 25, 35, and $55^{\circ}C$) for 20 weeks. Samples were taken every week during incubation depending on the given conditions. S. enterica persisted for up to 1 day in livestock manure compost at $55^{\circ}C$, over 140 days at $10^{\circ}C$, 140 days at $25^{\circ}C$, and 70 days at $35^{\circ}C$, respectively. S. aureus persisted for up to 1 day in livestock manure compost at $55^{\circ}C$ and 90 days at $10^{\circ}C$, 70 days at $25^{\circ}C$, and 40 days at $35^{\circ}C$, respectively. The results indicate that S. enterica and S. aureus persisted longer under low temperature condition. S. enterica survived longer than S. aureus at three different temperatures (10, 25, and $35^{\circ}C$). This study will provide useful and practical guidelines to applicators of soil in deciding appropriate handling and time frames for land application of livestock manure compost for sustainable agriculture. Results from these studies provide useful information in identifying manure handling practices to reduce the risk of S. enterica and S. aureus transmission to fresh produce.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.828-834
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• 2010

An ethanol-producing yeast strain, CHFY0201, was isolated from soil in South Korea using an enrichment technique in a yeast peptone dextrose medium supplemented with 5% (w/v) ethanol at $30^{\circ}C$. The phenotypic and physiological characteristics, as well as molecular phylogenetic analysis based on the D1/D2 domains of the large subunit (26S) rDNA gene and the internally transcribed spacer (ITS) 1+2 regions, suggested that the CHFY0201 was a novel strain of Schizosaccharomyces pombe. During shaking flask cultivation, the highest ethanol productivity and theoretical yield of S. pombe CHFY0201 in YPD media containing 9.5% total sugars were $0.59{\pm}0.01$ g/l/h and $88.4{\pm}0.91%$, respectively. Simultaneous saccharification and fermentation for ethanol production was carried out using liquefied cassava (Manihot esculenta) powder in a 5-l lab-scale jar fermenter at $32^{\circ}C$ for 66 h with an agitation speed of 120 rpm. Under these conditions, S. pombe CHFY0201 yielded a final ethanol concentration of $72.1{\pm}0.27$ g/l and a theoretical yield of $82.7{\pm}1.52%$ at a maximum ethanol productivity of $1.16{\pm}0.07$ g/l/h. These results suggest that S. pombe CHFY0201 is a potential producer for industrial bioethanol production.

• Microbiology and Biotechnology Letters
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• v.34 no.2
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• pp.174-179
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• 2006

Bacterium capable of using biphenyl as a sole source of carbon and energy were isolated from soil, and based on the results of 16S rDNA sequence, strain BK10 identified as a Sphingobium yanoiktiyae. The optimum cultural conditions were as follows; $NH_4NO_3$ 1g, $K_2HPO_4$ 1g, $MgSO_4{\cdot}7H_2O$ 0.5g, $CaCO_3$ 0.2 g per 1 liter of distilled water. The Sphingobium yanoikuyae BK10 strain was completely utilized biphenyl in mineral salt media containing biphenyl at concentration 500 $\mu$g/ml of biphenyl as a sole carbon and energy source within 48 hours. Optimumal pH and temperature for biphenyl degradation and cell growth of strains were 6.0$\sim$8.0 and 20$\sim$50$^{\circ}C$, respectively. Especially, at 30$^{\circ}C$, cell-growth were higher than other temperature. Cell grown on biphenyl has been shown to have a higher removal rate for biphenyl than grown on sucrose. This study shows that Sphingobium yanoikuyae BK10 strain had a high biodegradation capability of biphenyl and can be simulate a candidate compounds the bioremediation of PCBs (Polychlorinated biphenyl) contaminant soil and water.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.2
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• pp.258-264
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• 2014

This study investigated the effects of die temperature and repeated extrusion on the chemical components and antioxidant properties of extruded white ginseng (EWG). Die temperature was adjusted to 100, 120, and followed by repeated extrusion under the same conditions with corresponding samples. Secondary extruded white ginseng (SEWG) at a die temperature of $120^{\circ}C$ had the highest acidic polysaccharide content of all extrudates. Increasing die temperature and repeated extrusion both increased crude saponin content of the extrudate. Ginsenoside Rh1 was detected in the EWG ($140^{\circ}C$) and SEWGs, whereas ginsenosides Rg3s and Rg3r were only detected in SEWG ($140^{\circ}C$). The highest total phenolic content, DPPH radical scavenging activity, and reducing power obtained from SEWG ($140^{\circ}C$) were $8.55{\pm}0.03$ mg/g, $72.05{\pm}0.63%$, and $0.80{\pm}0.004$, respectively. In conclusion, repeated extrusion increases antioxidant activity and crude saponin contents for the development of improved ginseng products.

• Journal of Pharmacopuncture
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• v.3 no.2
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• pp.153-168
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• 2000

This study was designed to study on major components of various Bee Venom(Bee Venom by electrical stimulation in Korea; K-BV I, Bee Venom by Microwave stimulation in Korea; K -BV II, 0.5rng/ml, Fu Yu Pharmaceutical Factory, China; C-BV, 1mg /ml, Monmouth Pain Institute, Inc., U.S.A.; A-BV) using Electrophoresis. The results were summarized as follows: 1. In 1:4000 Bee Venom solution rate, the band was not displayed distinctly usmg Electrophoresis. But in 1: 1000, the band showed clearly. 2. The results of Electrophoresis at solution rate 1:1000, K-BV I and K-BVII showed similar band. 3. The molecular weight of Phospholipase $A_2$ was known as 19,000 but its band was seen at 17,000 in Electrophoresis. 4. Protein concentration of Bee Venom by Lowry method was different at solution rate 1:4000 ; C-BV was $250{wmu}g/ml,\;K-BV\;I\;was\;190{wmu}g/ml,\;K-BVII\;was\;160{wmu}/ml\;and\;C-BV\;was\;45{wmu}/ml5$. Electrophoresis method was unuseful for analysis of Bee Venom when solution rate is above 1:4000 but Protein concentration of Bee Venom by Lowry method was possible. These data from the study can be applied to establish the standard measurement of Bee Venom and prevent pure bee venom from mixing of another components. I think it is desirable to study more about safety of Bee Venom as time goes by.