• 대한전기학회논문지
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• 제41권3호
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• pp.253-260
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• 1992

In this study, the dielectric, structural and electrical properties of Pb(ZnS11/3TNbS12/3T)OS13T-BaTiOS13T-PbTiOS13T system ceramics were investigated with respect to the variation of YS12TOS13T addition amount. As the YS12TOS13T addition amount is increased, the resistivity at 100$^{\circ}C$ and the resonant/antiresonant frequencies and the frequency constant are slowly increased, and the grain growth is restrained until 0.4 wt% YS12TOS13T addition amount but continuously increased with the addition amount more than 0.4 wt% YS12TOS13T. As the YS12TOS13T addition amount is increased, the density, the diffuseness of dielectric constant and the induced polarization are increased until 0.4 wt% YS12TOS13T addition.

• 한국분말재료학회지
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• 제3권2호
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• pp.86-90
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• 1996

The effects of added VC, Cr$_3$C$_2$ and TaC on the microstructures and properties of submicron WC-10%Co cemented carbides. The relative sintered density of compact was increased by addition of Cr$_3$C$_2$ but decreased oppositely by addition of VC or TaC. The growth of WC grains was significantly suppressed by addition of these carbides. The hardness of these alloys was increased by addition of other carbides and showed a maximum value by simultaneously added VC and Cr$_3$C$_2$. The transverse rupture strength(T.R.S.) was in- creased by addition of Cr$_3$C$_2$, while it was decreased by addition of VC or TaC. The relative sintered density and T.R.S. of these alloys were improved by HIP-treatment. The maximum T.R.S. was 328kg/mm$^2$ in the Wc-10%Co cemented carbide with addition of 0.5%VC.

• 한국세라믹학회지
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• 제31권12호
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• pp.1417-1422
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• 1994

Effect of MgO, CaSO4, and CaF2 addition on the formation of clinker minerals in portland cement have been investigated by measuring the amounts of free-CaO and C3S in the fired specimens and analyzing the Mg and S concentration in C3S and C2S. It was found that CaSO4 inhibited C3S formation but MgO addition offset this effect of CaSO4. MgO addition also enhanced the mineralizing effect of CaSO4+CaF2, resulting in the acceleration of C3S formation. It was suggested that Mg might inhibit the formation of sulphate compounds rim around C2S and thus C2S+CaOlongrightarrowC3S reaction was facilitated.

• 한국식품과학회지
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• 제17권1호
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• pp.8-14
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• 1985

한국인의 기호에 맞는 상업적 된장의 풍미향상을 위하여 된장제조시 Bacillus licheniformis와 Saccharomyces rouxii를 첨가하여 $27^{\circ}C{\pm}\;1$에서 40일간 발효시킨 결과 B. licheniformis 와 S. rouxii의 첨가로 환원당의 증량이 억제되었고, S. rouxii는 에틸 알콜의 생산을 증가시키고 암모니아태 질소의 양을 감소시켰다. B. licheniformis는 아미노태 질소와 적정산도를 증가시켰다. A. oryzae의 생육은 숙성중 감소되었고 B. licheniformis와 S. rouxii의 첨가로 더욱 촉진되었다. B. licheniformis와 S. rouxii를 혼용한 시료에 유리아미노산 함량이 가장 많았으며 각시료 모두 휘발성 성분으로 아세트알데히드, 아세톤, 에틸 알콜, 에틸 아세테이트, 메틸 알콜, 프로필 알콜, 이소부틸 알콜, 이소아밀 알콜 등이 검출되었으며 재래식 된장에서는 이소부틸 알콜, 이소아밀 알콜 등이 검출되지 않았다. 시료의 전체적인 풍미는 B. licheniformis 와 S. rouxii를 혼용한 시료가 가장 우수하였다.

• 한국주조공학회지
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• 제24권5호
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• pp.295-303
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• 2004

The effects of three minor elements, S, Ce and Bi, on the inoculation ability and fading behavior of 1.0 wt%Ba-Fe-Si were investigated through thermal analysis. The performance of 1.0 wt%Ba-Fe-Si inoculant was better and more consistant at the high temperature range of $1,450{\sim}1,500^{\circ}C$ than that of low one of $1,300{\sim}1,400^{\circ}C$. That was improved with individual addition of three minor elements. The optimum amount of addition was 1.0% of the weight of inoculant added, respectively. That was improved also by the simultaneous addition of two or three kinds of minor elements. Even though worse with the addition of two kinds of them simultaneously than with individual addition, that was improved with the simultaneous addition of all three kinds over that with the individual one.

• 한국식품과학회지
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• 제32권6호
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• pp.1319-1325
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• 2000

본 연구는 면역화된 산란계로부터 생산된 계란 난황중에 들어있는 S. mutans균주의 specific IgY를 분리하여 면역화 여부, Specific IgY 농도별 및 균수별에 따른 항균력을 현미경적 및 탁도측정에 의한 IgY의 항균력 효과를 검토하고자 실시하였다. 면역화 여부에 따른 탁도시험 결과 면역처리된 처리구에 crude IgY를 10%와 20% 첨가에 의해 항균 효과가 있었다. 면역을 하지 않은 닭에서 생산된 계란으로부터 추출한 IgY를 10% 첨가구와 대조구에서는 응집반응을 나타내지 않았다. 그러나 S. mutans로 면역화된 닭에서 생산된 계란에서 추출한 IgY의 10%첨가구는 상등액과 침전물에서는 균들이 응집되는 현상을 보였다. 면역화된 조난황 specific IgY를 첨가한 처리구가 대조구 보다 S. mutans균들이 응집되는 정도에 있어서 확실한 효과를 나타내었다. 조 난황 specific IgY의 농도별 시험에서는 5%이상 첨가구 들에서는 전반적으로 균체들의 응집현상이 나타났으며 IgY를 2.5% 이하로 첨가한 처리구와는 확연한 차이를 보였다. 탁도에 있어서도 조 난황 specific IgY 농도별 시험에서는 첨가농도에 따라 차이가 있었지만 10% 이상 첨가구에서는 탁월한 효과를 나타내었다. 응집된 균괴의 크기는 IgY첨가량이 증가할수록 점점 더 커져가는 현상을 나타내었다. 균수별에서는 $10^5\;cfu/mL$ 이상 접종구에서는 균체들이 응집되는 현상을 보였으며 균수가 많을수록 더욱 응집되는 현상을 나타내었다. Plaque 형성력은 감소하는 경향을 보였으며 IgY 농도 15%에서는 plaque 형성이 약 75%가 저해되었다. 따라서 면역화된 닭으로 부터 생산된 계란에서 추출된 crude IgY를 사용하여 S. mutans균으로부터 발생된 충치를 예방할 수 있을 것으로 사료되었다.

• Journal of Microbiology
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• 제33권4호
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• pp.315-321
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• 1995

The relationship between morphological differentiation and production of trypsin-like protease (TLP_ in streptomycetes was studied. All the Streptomyces spp.In this study produced TLP just before the onset of aerial mycelium formation. Addition of TLP inhibitor, TLCK, to the top surface of colonies inhibited aerial mycelium formation as well as TLP inhibitor, TLCK, to the top surface of colonies inhibited aerial mycelium formation as well as TLP activity. Addition of 2% glucose to the Bennett agar medium repressed both the aerial mycelium formation and TLP production in S. abuvaviensis, S. coelicolor A3(2), S exfoliatus, S. microflavus, S. roseus, s. lavendulae, and S. rochei. However the addition of glucose did not affect S. limosus, S. felleus, S. griseus, S. phaechromogenes, and S. rimosus. The glucose repression on aerial mycelium formation and production of TLP was relieved by the addition of glucose anti-metabolite (methyl .alpha.-glucopyranoside). Therefore, it was concluded that TLP production is coordinately regulated with morphological differentiation and TLP activity is essential for morphological differentiation in streptomycetes. The proposed role of TLP is that TLP participates in the degradation of substrate mycelium protein for providing nutrient for aerial mycelial growth.

• 한국세라믹학회지
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• 제45권1호
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• pp.30-35
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• 2008

In this paper, CdS/Cd(Cu)S thin films and diodes were manufactured via a chemical bath deposition (CBD) process, and the effects of $NH_4Cl$ and TEA(triethylamine) on the properties of the films were examined. The addition of $NH_4Cl$ significantly increased the thickness of the CdS and Cd(Cu)S films, however, the addition of TEA decreased the thickness in both cases slightly. The addition of $NH_4Cl$ along with TEA increased the film thickness more effectively compared to the addition of only $NH_4Cl$. The thickness of the CdS film prepared from an aqueous solution of 0.007 M $CdSO_4$, 1.3 M $NH_4OH$, 0.03 M $SC(NH_2)_2$, 0.0001 M TEA and 0.03 M $NH_4Cl$ was 310 nm. Dark resistivity of the CdS film was $1.2{\times}10^3\;{\Omega}cm$ and the photo resistivity with $500\;W/cm^2$ irradiation of white light was $20{\Omega}cm$. The Cd(Cu)S/CdS thin film diodes prepared by CBD showed good rectifying characteristics.

• 한국조리학회지
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• 제11권3호
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• pp.179-189
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• 2005

The purpose of this study was to investigigate the effects of different tapioca powder on the quality of Chol-Pyon. As the result of the sensory evaluation, 5% addition groups showed good preference in chewness, moistness, softness, adhesiveness, after flavor. 10% addition groups showed good preference moistness, softness, after flavor. In texture profile, gumminess, cohesiveness, adhesiveness of Chol-Pyon was not different significantly among all the groups. All groups was getting higher by addition level. Softness was 5%, 20% addition groups had the higher. Tapioca Chol-Pyon seemed to increase hardness slightly. 5% addition group had the highest values in chewness. The desireable water content in 5%, 10% Tapioca Chol-Pyon was not different significantly among all the groups(p<0.05). 15%, 20% addition group was significantly different from all the groups. Hunter's rotor values higher redness and yellowness was 20% tapioca powder addition group more than the other groups but lightness were lowest value. Above results indicated that 5% tapioca powder addition level to give the best quality.

• 열처리공학회지
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• 제23권4호
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• pp.191-197
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• 2010

Zr addition is known as effective method to improve the anisotropy of steel due to the elongated MnS inclusions which are observed in hot forged steels. The aim of this research is to investigate the effect of Zr addition on the mechanical properties and manganese sulphide morphology of 0.27%C-Cr-Mo plastic mold steel. The ingots were prepared by vacuum induction melting and forged to ${\Phi}35mm$ round bar. Forged bars were quenched and tempered at $560{\sim}640^{\circ}C$ for 1 hour. Jominy test, microstructual observation, tensile test and Charpy impact test were conducted. The morphology of MnS inclusions was changed by Zr addition. The shape of MnS inclusions was not so much lengthened and controlled not to be elongated by Zr inclusions which surround the MnS inclusions. Tensile strength and yield strength of the tempered steels were not nearly affected by the addition of Zr, but elongation and reduction of area were decreased. Especially, the toughness of Zr added steels was deteriorated with increasing of Zr content. From the results of this study, it is assumed that anisotropy of steels was improved by the addition of Zr. However, impact toughness of the steel was significantly decreased by the excessive Zr addition (over 0.066%).