• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.6
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• pp.591-595
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• 1990

A promoting effect of ginseng saponin on the growth recovery rate of Saccharomyces rouxii which was treated by heat was confirmed in previous report(22). In order to deduce the promoting effect on the growth recovery of the heat stressed yeast, the effect of ginseng saponin on the activity and the heat stability of the amylase produced by Sacchirromyces rouxii were observed. The amylase showed the highst activity at 0.01％ of saponin. At this concentration, the activity increased about 23％ compared to the control. Furthermore, the ginseng saponin showed a protective effect against thermal inactivation of the amylase produced by Saccharomyces rouxii.

• YAKHAK HOEJI
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• v.32 no.1
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• pp.26-39
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• 1988

Eudragit $RS^{\circledR}$ polymer was used as a wall material for the microencapsulation of aspirin by a phase separation method from chloroform-cyclohexane system with 5% polyisobutylene (PIB) in cyclohexane, and microcapsules obtained were evaluated by particle size analysis, scanning electron microscopy (SEM), drug release and drug stability test. With PIB as a coacervation inducing agent, smooth and tight microcapsules with less aggregation were obtained. Below 1 : 0.3 core-wall ratio, it was possible to coat individual particle. Variation of production conditions showed that increasing the proportion of wall material, particle size and wall thickness of microcapsules and the concentration of paraffin wax in cyclohexane as a sealant sustained drug release rates effectively. SEM confirmed that larger microcapsules after drug release did not rupture into smaller particles but contained a few small pores on the surface. Aspirin release from Eudragit $RS^{\circledR}$ coated microcapsules was independent of the pH of medium, and the mechanism of drug release from non-sealed and sealed microcapsules appeared to fit Higuchi matrix model kinetics. Aspirin in the mixture of aspirin microcapsules and sodium bicarbonate was by far more stable than that in the mixture of pure aspirin and sodium bicarbonate.

• Bulletin of the Korean Chemical Society
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• v.25 no.8
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• pp.1137-1142
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• 2004

A spectrophotometric and first derivative spectrophotometric method was developed in aquatic Tween 80 micellar solutions for selective determination of nickel without using any pre-separation step. 1-(2-Pyridylazo)-2-naphthol (PAN), as a sensitive chromogenic complexing agent formed a red-colored Ni(II)-PAN complex in Tween 80 media with satisfactory solubility and stability. Conditions such as pH, PAN concentration, type and concentration of micellizing agent were optimized. Molar absorptivity of Ni-PAN complex was found $4.62\;{\times}\;10^4L\;cm^{?1}\;mol^{?1}$ at 569 nm, under the optimum condition. Calibration graphs were derived by zero, first and second derivative spectrophotometry at maximum wavelengths of 569, 578 and 571 nm with linear ranges of 30-1800, 20-2500 and 30-2000 ng $mL^{?1}$ , respectively. Precision as standard deviation as well as accuracy as recovery percent were in the range of 1-20 ng $mL^{?1}$, and 93.3-103.3%, respectively, for the entire of the linear ranges. Spectrophotometric detection limit was 3 ng $mL^{?1}$ and effects of diverse ions on the first derivative determination of nickel were studied to investigate selectivity of the method. Interferences of cobalt and copper on the nickel determination were prevented using o-phenanthroline as masking agent. The recommended procedures were applied to the various synthetic and stainless steel alloys, tea leaves and human hair, with satisfactory results.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3755-3760
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• 2012

Single crystals of lithium potassium phthalate (LiKP) were successfully grown from aqueous solution by solvent evaporation technique. The grown crystals were characterized by single crystal X-ray diffraction. The lithium potassium phthalate $C_{16}\;H_{12}\;K\;Li_3\;O_{11}$ belongs to triclinic system with the following unit-cell dimensions at 298(2) K;$a=7.405(5){\AA}$;$b=9.878(5){\AA}$;$c=13.396(5){\AA}$;${\alpha}=71.778(5)^{\circ}$;${\beta}=87.300(5)^{\circ}$;${\gamma}=85.405(5)^{\circ}$; having a space group P1. Mass spectrometric analysis provides the molecular weight of the compound and possible ways of fragmentations occurs in the compound. Thermal stability of the crystal was also studied by both simultaneous TGA/DTA analyses. The UV-Vis-NIR spectrum shows a good transparency in the whole of Visible and as well as in the near IR range. Third order nonlinear optical studies have also been studied by Z-scan technique. Nonlinear absorption and nonlinear refractive index were found out and the third order bulk susceptibility of compound was also estimated. The results have been discussed in detail.

• The Korean Journal of Ceramics
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• v.3 no.1
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• pp.52-56
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• 1997

The Pt doped $TiO_2$ composite membranes were prepared by the sol-gel process. The Pt doped titania sol was peptized with hydrochloric acid in the pH range of 1.23 to 1.32 at 5$0^{\circ}C$. The average particle size of the Pt doped titania sol was shown to be below 15nm and well dispersed in the solution. XPS show the Pt elements continuous and homogeneous dispersed in the $TiO_2$ membrane. The mean particle size of the Pt doped $TiO_2$ composite membrane has smaller than that of the undoped $TiO_2$ composite membrane. The average pore size of the Pt doped $TiO_2$ composite membrane was increased from 58 to 193 $\AA$ with firing temperature changed from 550 to 85$0^{\circ}C$. It was observed that the Pt doped $TiO_2$ composite membranes showed crack-free and homogeneous microstructue as well as narrow particle size distribution up to above 75$0^{\circ}C$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.4
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• pp.328-332
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• 2011

The formation of front metal contact silicon solar cells is required for low cost, low contact resistance to silicon surface. One of the front metal contacts is Ni/Cu plating that it is available to simply and inexpensive production to apply mass production. Ni is shown to be a suitable barrier to Cu diffusion into the silicon. The process of Ni electroless plating on front silicon surface is performed using a chemical bath. Additives and buffer agents such as ammonium chloride is added to maintain the stability and pH control of the bath. Ni deposition rate is found to vary with temperature, time, utilization of bath. The experimental result shown that Ni layer by SEM (scanning electron microscopy) and EDX analysis. Finally, plated Ni/Cu contact solar cell result in an efficiency of 17.69% on $2{\times}2\;cm^2$, Cz wafer.

• Journal of Ginseng Research
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• v.19 no.3
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• pp.237-243
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• 1995

Agmatine iminohydrolase (EC 3.5.3.12) catalyzes the hydrolysis of agmatine into putrescine. The enzyme seems to be one of the critical enzymes in putrescine biosynthesis. The enzyme was purified to homogeneity from Panax ginseng C.A. Meyer by combined method of ammonium sulfate 1 fractionation, DEAR anion exchange column, hydroxyapatite column and agmatine carboxyhexyl Sepharose 4B affinity column. The molecular weight estimated by native pore gadient polyacrylamide gel electrophoresis was 71, 000 Dalton, while that estimated by SDS-PAGE was 70, 000 Dalton, indicating a monomeric enzyme. The optimal pH and temperature were 9.0 and 37$^{\circ}C$, respectively. The Km and 1 Vmax for agmatine were 8.3 mM and 14.4 nmole/hr, respectively. Heat stability of this enzyme was high. The enzyme was observed to be inhibited by polyamines such as putrescine, cadaverine, spermidine and spermine. Especially, putrescine was a potent inhibitor of the purified enzyme. These results suggest that polyamines could be important in growth regulation of Panax ginseng C.A. Meyer.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.3
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• pp.371-378
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• 2007

Red ginseng has been considered a functional food, and many studies on red ginseng and the prevention of cancer, hypertension, arteriosclerosis and constipation have been conducted. In this study, white bread dough with 1, 2, 3, 4 or 5% red ginseng marc powder was measured by a farinograph, extensograph, amylograph, as well as for pH to evaluate the development time, stability, extensibility, resistance to extension, gelatinization temperature, and maximum viscosity temperature. The ash content of the wheat flour increased with an increasing content of red ginseng marc powder. The gelatinization maximum and the temperature for the gelatinization maximum of the flour-water suspension in the amylograph were not affected by the addition of red ginseng marc powder. The moisture absorption of the wheat flour in the farinograph increased as the content of red ginseng marc powder increased. Also, as the content of red ginseng marc powder increased, dough development time decreased. The extensibility of the dough in the extensograph showed a negative relationship with the amount of red ginseng marc powder added.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1457-1461
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• 2013

The $Fe_3O_4$-core and Ag-shell ($Fe_3O_4@Ag$ nanoeggs) were prepared through the encapsulation of 3-aminopropyltriethoxysilane-coated magnetite nanoparticle in nano-Ag shell by a simple chemically controlled procedure. The $Fe_3O_4@Ag$ nanoeggs were characterized by scanning electron microscopy, transmission electron microscopy, UV-vis spectrum and superconducting quantum interference device magnetometer, respectively. A detailed analysis is provided of how the hydrolysis and condensation of 3-aminopropyltriethoxysilane and the pH value are vital in fabricating the $Fe_3O_4@Ag$ nanoeggs. The prepared $Fe_3O_4@Ag$ nanoeggs possessed uniform size, improved monodispersity, stability against aggregation and high magnetization, which were utilized for the detection of latent fingerprints deposited onto different surfaces. The experimental results showed that the latent fingerprints developed with the $Fe_3O_4@Ag$ nanoeggs powders exhibited excellent ridge details with minimal background staining.

• Korean Journal of Food Science and Technology
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• v.10 no.1
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• pp.11-15
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• 1978

Barley (variety, Bangsa No. 6) was milled on a stone mill with 60% flour extraction. Rheological and baking properties of composites containing 5 and 10% of the barley flour with wheat flour (11.4% protein) were investigated. As the barley flour level was increased, amylograph paste viscosities increased at all reference points and farinograph stability decreased. However, no significant differences were noted in the proportional number measured with extensigraph with the various flours. Loaf volume and the staling rate of bread decreased and increased respectively as the barley flour level was increased.