• 한국세라믹학회지
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• 제28권5호
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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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• 제5권3호
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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.

• 한국식품저장유통학회지
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• 제23권3호
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• pp.361-368
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• 2016

본 연구는 꽃송이버섯 원물과 꽃송이버섯 8% 첨가하여 유산균으로 발효한 꽃송이버섯 혼합물의 이화학적 특성 및 항산화 활성을 비교 조사하였다. 유산균 발효 꽃송이버섯 혼합물의 수분, 조지방 및 조회분 함량은 버섯 원물에 비해 유의적으로 높게 나타났다(p<0.05). 꽃송이버섯원물과 유산균 발효 꽃송이버섯 혼합물의 총 식이섬유소 중 불용성 식이섬유소가 각각 89.21%와 95.74%를 차지하였다. 꽃송이버섯 원물의 ${\beta}$-glucan 함량은 38.03%으로 유산균 발효 꽃송이버섯 혼합물의 ${\beta}$-glucan 함량 5.44%에 비해 유의적으로 높게 나타났다. 꽃송이버섯 원물에는 유리당 중 glucose와 fructose만 함유하고 있으며, 유산균 발효 꽃송이버섯 혼합물은 sucrose만을 함유하였다. 총 polyphenol 함량은 꽃송이버섯 원물과 유산균 발효 꽃송이버섯 혼합물에서 유의적인 차이는 나타나지 않았다. 총 flavonoid 함량은 유산균 발효 꽃송이버섯 혼합물이 꽃송이버섯 원물에 비하여 유의적으로 높게 나타났다(p<0.05). DDPH radical 소거능은 꽃송이버섯 원물과 발효 꽃송이버섯 혼합물에서 유의적인 차이는 나타나지 않았으나, 대조군인 비타민 C에 비해서는 유의적으로 낮은 DDPH radical 소거능을 나타냈다(p<0.05). ABTS radical 소거능은 유산균 발효 꽃송이 버섯 혼합물이 꽃송이 버섯 원물에 비해 유의적으로 높은 것으로 나타났으며, 대조군인 비타민 C와는 유의적인 차이를 보이지 않았다(p<0.05). 꽃송이버섯 원물과 유산균 발효 꽃송이버섯 혼합물의 항산화지수도 비슷한 경향을 보였고, 대조군인 비타민 C에 비해서는 낮았으나, 시료를 첨가하지 않는 음성대조군 보다는 높게 나타났다. 따라서 유산균 발효 꽃송이버섯 혼합물은 항산화 작용에 긍정적인 영향을 미칠 수 있는 천연소재로서 산업적 활용이 가능할 수 있을 것이다.

• Journal of Pharmaceutical Investigation
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• 제27권4호
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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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• 제9권3호
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• pp.294-298
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• 1994

$CaCl_2$, glucose, frutose, glutamine, glutamate 그리고 Ii pids와 같은 배지 첨가물들이 회분식 그리고 연속식 2단계 생물반응기 시스템에셔 재조합 ${\beta}$-galactosidase (${\beta}$-gal) 생산을 증진시키는가를 조사하였다. Sf 21 세포에 AcNPV의 감염시 $CaCl_2$, frutose, glutamate, cholesterol 및 tocoph eral과 같은 배지 첨가물을 첨가하였을 때 ${\beta}$-gal 생산이 증진되었다. 30mM $CaCl_2$, 2.2mM frutose, 4.lmM glutamine, 그리고 O.34mM cholesterol이 보강된 감염 배 지를 이용한 재조합${\beta}$-gal 생산은 약 40% 의 증가를 보였다.

• 한국자동차공학회논문집
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• 제10권4호
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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.

• 한국약용작물학회지
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• 제3권2호
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• pp.151-155
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• 1995

국화과 식물인 산씀바귀(Lactuca raddeana)를 식물화학적 방법에 의하여 연구한 바 primaylong chain alcohol인 1-hexacosanol과 1-tetracosa not을, triterpene acetate로 ${\beta}-amyrin\;acetate,\;{\alpha}-amyrin acetate$, lupeol acetate, pseudotaraxasterol acetate, taraxasterol acetate 및 germanicol acetate등을, fatty acyl triterpene은 이들의 구성 triter pone alcohol이 triterpone acetate의 경우와 같았으며 acyl moiety는 myristate, palmitate, stearate및 arachidate로 각각 나타났다.

• 한국세라믹학회지
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• 제50권6호
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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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• 제26권1호
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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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• 제55권4호
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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.