• Preventive Nutrition and Food Science
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• 제14권3호
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• pp.252-259
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• 2009

We previously isolated Bacillus strains with high fibrinolytic activities (FAs) from cheonggukjang prepared by traditional ways. To test their potential as starters for cheonggukjang, soybean was fermented for 72 hr at $37^{\circ}C$ with each isolate and a control lab strain: B. subtilis CH3-25 (BS3-25), B. amyloliquefaciens CH51 (BA51), B. amyloliquefaciens CH86-1 (BA86-1), and B. subtilis 168 (BS168, control, lab strain). Viable cell numbers of all cheonggukjang samples rapidly increased and reached about $10^9$ CFU/g after 6 hr. During 72 hr, the initial pH of 6.3 rapidly increased to 8.1$\sim$8.2 for cheonggukjang fermented with BS3-25 or BA86-1, and 7.3 for those with BA51 or BS168. FAs and protease activities (acid, neutral, and alkaline) rapidly increased in cheonggukjang fermented with BS3-25, BA51, or BA86-1 during the first 12 hr. On the other hand, those of cheonggukjang fermented with BS168 slightly increased during the first 36 hr. There were significant changes in acid and neutral protease activities in cheonggukjang fermented with BA51 or BA86-1 during the 24 hr. Rapid increases of $\beta$-glucosidase activity corresponded well with rapid increases of $\alpha$-amylase and $\alpha$-galactosidase activities in addition to increases in antioxidant activities and the TPCs (total phenolic contents). The highest increase in the TPCs was observed in cheonggukjang fermented with BA86-1 while the least was that fermented with BS168.

• 한국수소및신에너지학회논문집
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• 제23권6호
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• pp.581-587
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• 2012

Thermal aging effect on NSR kinetics was studied over Pt/Co/Fe/Ba/$Al_2O_3$ catalyst. The amount of $NO_x$ uptake over Pt/Co/Fe/Ba/$Al_2O_3$ calcined at $400^{\circ}C$ increased with increasing NSR temperature from $200^{\circ}C$ to $400^{\circ}C$, where amount of $NO_x$ uptake is the highest at $400^{\circ}C$ with mol ratio of $NO_x$/Ba = 0.5. Thereafter, the amount of $NO_x$ uptake at $400^{\circ}C$ decreased with the higher calcination temperature, where Pt/Co/Fe/Ba/$Al_2O_3$ catalyst calcined at $700^{\circ}C$ showed an amount of $NO_x$ uptake with the mol ratio of $NO_x$/Ba=0.062. Result of XRD and NSR showed that Fe addition into Pt/Co/Fe/Ba/$Al_2O_3$ suppressed sintering of Pt crystallites and make $NO_x$ uptake larger, compared to no addition of Fe into Pt/Co/Fe/Ba/$Al_2O_3$ catalyst. From BET result, it was found that the change of specific surface area was relatively small by the thermal aging process. Therefore, it was found that the sintering of Pt crystallites caused the decrease of $NO_x$ uptake during NSR reaction and Fe played a role to suppress the sintering process of Pt crystallites caused by thermal aging.

• 한국재료학회지
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• 제23권6호
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• pp.334-338
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• 2013

In this study, $BaTiO_3$ thin films were grown by RF-magnetron sputtering, and the effects of the thin film thickness on the structural characteristics of $BaTiO_3$ thin films were systematically investigated. Instead of the oxide substrates generally used for the growth of $BaTiO_3$ thin films, p-Si substrates which are widely used in the current semiconductor processing, were used in this study in order to pursue high efficiency in device integration processing. For the crystallization of the grown thin films, annealing was carried out in air, and the annealing temperature was varied from $700^{\circ}C$. The changed thickness was within 200 nm~1200 nm. The XRD results showed that the best crystal quality was obtained for ample thicknesses 700 nm~1200 nm. The SEM analysis revealed that Si/$BaTiO_3$ are good quality interface characteristics within 300 nm when observed thickness. And surface roughness observed of $BaTiO_3$ thin films from AFM measurement are good quality surface characteristics within 300 nm. Depth-profiling analysis through GDS (glow discharge spectrometer) showed that the stoichiometric composition could be maintained. The results obtained in this study clearly revealed $BaTiO_3$ thin films grown on a p-Si substrate such as thin film thickness. The optimum thickness was 300 nm, the thin film was found to have the characteristics of thin film with good electrical properties.

• 한국자원식물학회지
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• 제15권1호
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• pp.43-49
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• 2002

옻나무의 묘목생산성을 높이기 위하여 근삽에 있어서 BA의 처리방법과 삽식법을 공시하였다. 삽식 당일에 삽수를 1,000 mg/L BA 용액에 1분간 침지처리가 적하법보다 초기에 신초의 발생율은 낮았으나 5주 이후부터 급격하게 증가하여 10주 후에 는 약 85%로 가장 높았으며, 적하법에서는 BA의 처리 간격이 신초의 발생에 큰 영향이 없었다. 2일 간격으로 100 ${\mu}\ell$의 BA를 적하한 삽수에서 수장이 가장 컸으며 엽수도 많았고, 다음으로 침지처리가 묘소질에 효과적이었다. 분지의 발생은 침지처리구 보다는 적하처리구의 유묘가 삽수와 가까운 지점에서 발생하였다. 평삽이 사삽과 직삽에 비하여 신초의 발생이 약 1주일 빨랐고 신초의 발생도 3주 이후부터 6주까지 급격하게 증가하는 경향이었는데, 삽식 10주 후의 신초발생율은 약 96%로 가장 높았다. 평삽구의 묘가 약 40cm로써 가장 컸으며 평삽구의 묘가 약 40cm로써 가장 컸으며 제 1분지의 발생부위도 낮은 경향이었다. 평삽의 경우 각각 다른 부분에서 발생하는 2~3개의 신초를 각각 분리하여 하나의 묘목으로 생육시킴으로써 묘목의 대량증식에 효과적이었다.

• 한국전기전자재료학회논문지
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• 제33권6호
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• pp.483-489
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• 2020

BaTiO₃ powder was synthesized by a solid-state reaction using BaCO₃ and TiO₂. Different calcination temperatures (800℃, 850℃, 900℃, and 950℃) were set to investigate their effects on the properties of BaTiO₃ powder. The synthesized BaTiO₃ phase was confirmed to be a single phase by XRD, and the tetragonality (c/a) and crystallite size were calculated. Thereafter, each calcinated BaTiO₃ was sintered at five different sintering temperatures (1,100℃, 1,150℃, 1,200℃, 1,250℃, and 1,300℃), and the tetragonality, density, porosity, dielectric constant, and grain size were measured. As the calcination temperature increased, the tetragonality and crystallite size also increased, to 1.008 and 66 nm, respectively, at 950℃. Moreover, most pellets showed increased density, dielectric constant, and tetragonality as the sintering temperature increased up to 1,250℃; the same parameters slightly decreased at 1,300℃. It is noteworthy that the tetragonality of BaTiO₃ at 1,250℃ exhibits a very high c/a value of 1.0084. In addition, the grain size and dielectric constant measured near the Curie temperature increased as the sintering temperature increased.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2002년도 총회 및 추계학술발표회
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• pp.107.2-108
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• 2002

Barley Yellow Mosaic Virus(BaYMV) is responsible for ane of the most improtant disease in malting Barley in Korea. It is transcitted by soil borne fungus, Polymyza graminis To estimate the occurrence pattern of BaYMV by the physio-chemical property of soil collected from farmer's sield, this study was conducted. The rate of didsease occurrence to BaYMV investigated at 19 spots of 10th regions. The sample soil was collected by 20 pots among an ifected field and analyzed th soil characters in 2002. The rate of disease occurrence to BaYMV was about 79%,60%,65% in Sacheon, Kosung and Hadong areas, respectively, which is malting Barley growing regions but Pohang, Yeongduk, Euesung, Gunwee, which are growing Covered Barley doesn't infected BaYMV. The tested of RT-PCR was showed that the BaYMV, BMMV.SBWMV. were identified in Milyang but the others regions was infected only to BaYMV. The physio-chemical property of soil collected from infected soil show various range such as pH(4.98~8.05), EC(0.44~2.7%),OM(1.61~6.85), P2O5958~519), K(0.22~1.82), Ca(2.3~9.7), Mg(0.5~2.6), Na(0.14~0.43) The correlation coefficient between physio-chemical property fo the infected soil and infection rate shows significant to pH at 5% level. Although OM and Ca were high scores, it doesn't significant at 5% but it need to be more study in future.

• 한국재료학회지
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• 제7권1호
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• pp.57-61
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• 1997

$Y_{0.8}Ta_{0.2}O_{1.7}$-MO(M=Ba, Sr, Ca 및 Mg) 계에서의 형석구조의 생성과 이와 관련된 구조에 관하여 연구하였다. BaO또는 SrO를 4mol% 첨가한 조성에서는 결함형석구조 이외에 입방정 perovskite형 규칙구조인 $Ba_{2}YTaO_{6}$ 및 $Sr_{2}YTaO_{6}$와 입방정 $Y_{2}O_{3}$가 관찰되었다. CaO를 첨가한 경우에는 8mol%이상을 첨가한 조성에서부터 단사정 $Ca_{2}YTaO_{6}$와 $Y_{2}O_{3}$의 2차상이 나타났다. MgO의 경우에는 12mol% MgO를 첨가한 조성까지는 형석구조의 단일상을 나타내어 MgO가 형석구조에 고용되는 것을 알수 있었으며, 16 mol%조성부터는 2차상으로 MgO가 관찰되었다. 그러므로 위의 계에서 형석구조의 생성은 $A_{2}$(B'B")$O_6$의 생성과 첨가된 양이온의 크기에 영향을 받는 것으로 생각된다.생각된다.

• 생명과학회지
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• 제16권3호
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• pp.510-515
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• 2006

담배에서 기내 생장, 엽록소 및 광합성 효소인 rubisco와 rubisco activase에 미치는 벤질 아데닌(BA)의 영향을 연구하였다. 여러 농도의 BA 처리 후 11주에 2 ${\mu}M$의 농도에서 기내 생장과 엽록소의 함량이 가장 현저하였다. Rubisco의 함량은 BA의 농도가 증가함에 따라 같이 증가하여 2 ${\mu}M$에서 가장 높았으나, 이후 농도의 증가에 따라 감소함으로서 억제 현상을 보였다. Rubisco의 활성 또한 함량과 같은 현상을 나타냈다. 이 결과들은 rubisco의 활성이 함량과 연관되어 있음을 의미한다. Rubisco에 대한 이러한 효과가 rubisco activase와 관련되어 있을 것이라는 가정하에 이 효소의 함량과 활성을 측정한 결과, 2 ${\mu}M$ BA에서 가장 증가하였다. 이러한 결과들을 종합하면 BA에 의한 rubisco의 활성화 효과는 rubisco activase와 관련되어 있음을 보여준다.

• 한국자기학회지
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• 제6권4호
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• pp.251-257
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• 1996

기존의 침상형 매체와는 다르게 자기기록용 치환형 Ba-ferrite(BaM) tape의 보자력은 입자특성, 치환이온의 종류 및 tape 제조조건에 따라 분말의 보자력보다 50 Oe에서 600 Oe로 높게 나타났다. 이 보자력 증가는 육각판상 입자간 stacking 효과와 분말표면에 유기용제 흡착효과에 기인하였다. 동일한 입자크기와 판상비를 갖지만 치환이온이 다른 BaM 분말을 사용한 수평배향된 tape의 경우 입자간 stacking 효과에 의한 보자력 증가는 100 Oe에서 120 Oe 사이로 일정하여 치환이온의 종류에 무관하였다. 치환형 BaM 분말표면에 유기용제 흡착은 활성화 흡착과정에 의해 이루어졌으며, 유기용제 흡착에 의한 보자력 증가는 Co 이온이 함유된 BaM tape에서만 나타났다. Co-Ti 치환된 BaM의 경우 tape 제조시 사용된 유기용제 MEK(methyl ethyl ketone), TOL(toluene) 및 CHO (cyclohexanone) 중에서 CHO가 보자력 증가에 가장 크게 기여하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.180-181
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• 2009

$(Ba_{0.6},Sr_{0.3}Ca_{0.1})TiO_3$ powders, which were prepared by sol-gel method using a solution of Ba-acetate, Sr-acetate and Ca-acetate and Ti iso-propoxide, $(Ba_{0.6},Sr_{0.3}Ca_{0.1})TiO_3$ array thick films doped with 0.1 mol% $MnCO_3$ and $Yb_2O_3$ (0.1~0.7 mol%) were fabricated by the screen printing method on the alumina substrate. And the structural and electrical properties as a function of $Yb_2O_3$ amount were investigated. The thickness of all (Ba,Sr,Ca)$TiO_3$ thick films was approximately 60mm. The Curie temperature of doped with 0.1 mol% $Yb_2O_3$ specimen was $45^{\circ}C$, and the dielectric constant and at this temperature was 1062.