• Journal of the Korean Ceramic Society
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• v.28 no.5
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• pp.390-398
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• 1991

$\beta$-Sialon powder was prepared from Wando pyrophyllite by the carbothermic reduction and nitridation at 135$0^{\circ}C$ for 10 h nitrogen atmosphere. Amorphous silica prepared from Si(OC2H5)4 was added to Wando pyrophyllite powder in order to control the final Z value. Two different methods were applied for synthesis of $\beta$-sialon powders. In Process A, the amorphous silica prepared from Si(OC2H5)4 was admixed to Wando pyrophyllite powder. Process B was started from the mixture of Wando Y2O3 was added to the synthesized $\beta$-Sialon powders as a sintering aid, and the mixed powders were hot pressed at 175$0^{\circ}C$ for 120 min in nitrogen atmosphere under 30 MPa. Their mechanical properties were compared. The maximum values of M.O.R., hardness and KIC were 667 MPa, 16 GPa and 6.3 MN/m3/2, respectively, and they are the values obtained form $\beta$-Sialon ceramics prepared by process A of Z=0.5.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.3
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• pp.215-218
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• 2000

Sialytrisaccharides based on $\beta$-galactosyldisaccharides were synthesized using $\beta$-galactosidase and trans-sialidase in one pot. Using $\beta$-galactosidase from Bacillus Ciculans and trans-sialidase from Trypanosoma cruzi simulaneously, 6mM sialyltrisaccharides composed of about 95% NeuAc$\alpha$(2,3)Gal$\beta$(1,4)GlcNAc and 5% NeuAc$\alpha$(2,3)Gal$\beta$(1,6)GlcNAc were produced from a reaction mixture containing 25mM o-nitropheny1-$\beta$-D-galsctolneuraminic acid. One beauty of this reaction was that a secondary hydrolysis of the disaccharide intermediate occurring between the activated galactopyranoside and N-acetylgucosamine was prevented. Using $\beta$-galactosidase from Escherichia cloi and the same trans-sialidase, 15mM sialyltrisaccharides composed of about 90% NeuAc$\alpha$(2,3)Gal$\beta$(1,6)GlcNac and 10% NeuAc$\alpha$(2,3)Gal$\beta$(1,4)GlcNAc were produced from a reaction misture containing 400nM galactose, 800nM N-acetylglucosylation rection between galactose and N-actylgucosamine was diminant since the disaccharide intermediate mainly resulted sreulted in the silylated product.

• Food Science and Preservation
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• v.23 no.3
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• pp.361-368
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• 2016

The objective of this study was to investigate the nutritional composition and antioxidant activity of a mixture of rice bran and bodies of Sparassis crispa fermented with lactic acid bacteria (LAB). LAB-fermented S. crispa mixture had higher water, crude lipid and crude ash content than that of S. crispa. Insoluble dietary fiber contents of the dried powder of S. crispa and LAB-fermented S. crispa mixture were 46.13% and 33.46%, respectively. ${\beta}$-glucan was higher in dried S. crispa (38.03%) than in LAB-fermented S. crispa mixture (5.44%). Dried S. crispa contained mainly fructose and glucose instead of containing sucrose in LAB-fermented S. crispa mixture. No significant differences in the total polyphenol contents were found in between dried S. crispa and LAB-fermented S. crispa mixture. Total flavonoid content was significantly higher in LAB-fermented S. crispa mixture than in dried S. crispa. No significant differences were found in the DPPH radical scavenging activity and in the antioxidant index between dried S. crispa and LAB-fermented S. crispa mixture. Finally, ABTS radical scavenging activity of LAB-fermented S. crispa mixture was significantly higher than that of dried S. crispa. These results may provide the basic data for future studies for a better understanding of the biological activities of LAB-fermented S. crispa mixture.

• Journal of Pharmaceutical Investigation
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• v.27 no.4
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• pp.265-269
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• 1997

An inclusion complex of muscone with ${\beta}-cyclodextrin$ (CD), as a solid form of muscone, was prepared to increase the solubility of muscone. The molar ratio of muscone to ${\beta}-CD$ in complex was in the range of $1:1{\sim}1:5$ when prepared by freeze-drying method. The interaction of muscone with ${\beta}-CD$ in solid state was investigated by Infrared (IR) spectroscopy and differential scanning calorimetry (DSC). IR and DSC studies between $muscone-{\beta}-CD$ inclusion complex and physical mixture showed that $muscone-{\beta}-CD$ inclusion complex was prepared stably. From the amount of muscone incorporated in the inclusion complex, it was found that the molar ratio of muscone : ${\beta}-CD$ was 1:1. Relative spatial position of muscone and ${\beta}-CD$ was observed by Hyperchem molecular modelling program.

• KSBB Journal
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• v.9 no.3
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• pp.294-298
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• 1994

The medium additives such as CaCl2, glucose, fructose, glutamine, glutamate and lipids were examined to enhance recombinant ${\beta}$-galactosldase(${\beta}$-gal) production in batch and continuous two-stage bioreactor systems. The presence of each medium additive such as CaCl2, fructose, glutamate, cholesterol and tocopherol at AcNPV infection of Sf 21 cells had an effect on improved ${\beta}$-gal production. The recombinant ${\beta}$-gal production using the infection media supplemented with a mixture of 30mM $CaCl_2$, 2.2mM fructose, 4.1mM glutamate and 0.34mM cholesterol was increased by about 40%.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.4
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• pp.15-22
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• 2002

As the emission regulations on the automobiles have been increasingly stringent, precise control of air/fuel ration is one of the most important issues on the gasoline engines. Although many researches have been carried out to identify the fuel transport phenomena in the port fuel injection gasolines, mixture preparation in the cylinder has not been fully understood due to the complexity of fuel film behavior, In this paper, the mixture preparation during cold engine start is studied by using a Fast Response Flame ionization Detector.(FRFID) In order to estimate the transportation of injected fuel from the intake port into cylinder, the wall wetting fuel model was used. The two coefficient($\alpha$,$\beta$) of the wall-wetting fuel model was determined from the measured fuel mass that was inducted into the cylinder at the first cycle after injection cut-in. $\alpha$( ratio of directly inducted fuel mass into cylinder from injected fuel mass) and $\beta$ (ratio of indirectly inducted fuel mass into cylinder from wall wetted fuel film on the wall) was increased with increasing cooling water temperature. To reduce a air/fuel ratio fluctuation during cold engine start, the appropriate fuel injection rate was obtained from the wall wetting fuel model. Result of air/fuel ratio control, air/fuel excursion was reduced.

• Korean Journal of Medicinal Crop Science
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• v.3 no.2
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• pp.151-155
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• 1995

Chromatographic separation of Laduca raddeana extract afforded a mixture of fatty acyl triterpene, triterpene acetates and primary long chain alcohol. The kind of triterpene moieties in these two triter­penoids was six, i.e., ${\beta}-amyrin,\;{\alpha}-amyrin$, lupeol, pseudotaraxasterol, taraxasterol and germanicol on the basis of chemical and spectroscopic methods. The acyl moieties in the corresponding acyl mixture were characterized as acetates, myristate, palmitate, stearate and arachidate. And a mixture of primary long chain alcohol were composed of teracosanol and hexacosanol.

• Journal of the Korean Ceramic Society
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• v.50 no.6
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• pp.429-433
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• 2013

Silicon, carbon, and B4C powders were used as raw materials for the fabrication of porous SiC. ${\beta}$-SiC was synthesized at $1500^{\circ}C$ in an Ar atmosphere from a silicon and carbon mixture. The synthesized powders were pressed into disk shapes and then heated at $2100^{\circ}C$. ${\beta}$-SiC particles transformed to ${\alpha}$-SiC at over $1900^{\circ}C$, and rapid grain growth of ${\alpha}$-SiC subsequently occurred and a porous structure with elongated plate-type grains was formed. The mechanism of this rapid grain growth is thought to be an evaporation-condensation reaction. The mechanical properties of the fabricated porous SiC were investigated and discussed.

• The Plant Pathology Journal
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• v.26 no.1
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• pp.49-56
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• 2010

Thirty-six isolates of Colletotrichum spp. were obtained from infected grapes in two different locations of Korea; 18 isolates from Cheonahn, where carbendazim (MBC) and the mixture of MBC and diethofencarb (NPC) had been applied to control grape ripe rot, and 18 isolates from Cheongju, where no fungicides had been used. Sequences analysis of the internal transcribed spacer (ITS) and the $\beta$-tubulin gene identified 34 of the 36 isolates as Colletotrichum gloeosporioides. The remaining two isolates from Cheongju were identified as C. acutatum. Of the 18 isolates from Cheonahn, 12 were resistant to both MBC and the mixture (MBC+NPC), and six were sensitive to them. All C. gloeosporioides isolates from Cheongju, but not the two C. acutatum isolates, were sensitive to these fungicides. Sequence analysis of the $\beta$-tubulin gene in all isolates revealed that C. gloeosporioides resistant to MBC and MBC+NPC had a tyrosine instead of phenylalanine at the amino acid position 200. The appearance of resistance to MBC and the mixture in C. gloeosporioides correlated with the history of fungicide application in Korea.

• Journal of Animal Science and Technology
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• v.55 no.4
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• pp.289-293
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• 2013

The objective of this study was to assess the effects of dietary carbohydrases on growth performance, nutrient digestibility and blood characteristics in finishing pigs. A total of 90 pigs [(Landrace ${\times}$ Yorkshire) ${\times}$ Duroc] (initial BW = $56.15{\pm}1.26kg$) were used for a 35 d feeding trial. The dietary treatments included: 1) CON (control diet), 2) MIX (CON + mixture with ${\alpha}$-galactosidase and ${\beta}$-mannanase 0.05%) and 3) MAN (CON + ${\beta}$-mannanase 0.05%). There were six replications per treatment with five pigs per pen. The average daily gain (ADG) in MIX was higher than in CON (p<0.05). No significant differences were noted in the average daily feed intake (ADFI) and feed efficiency (G:F) among dietary treatments (p>0.05). Apparent total tract digestibility (ATTD) of dry matter (DM) and energy (E) in MIX increased (p<0.05) relative to CON and MAN. The ATTD of nitrogen (N) in MIX was higher (p<0.05) than in CON. No differences in red blood cells (RBC), white blood cells (WBC), lymphocytes and IgG concentrations were observed among dietary treatments (p>0.05). In conclusion, the addition of the mixture of carbohydrases (${\alpha}$-galactosidase and ${\beta}$-mannanase 0.05%) increased ADG and nutrient digestibility in finishing pigs.