• Corrosion Science and Technology
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• 제18권6호
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• pp.285-291
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• 2019

In this study, the corrosion characteristics of T22 and T92 steel were investigated in 6O₂ + 16CO₂ + 2SO₂ gas environment at 650 ℃. Corrosion characteristics were characterized by weight gain, oxide layer thickness, scanning electron microscope, optical microscope, energy dispersive X-ray spectroscopy, and X-ray diffraction. T22 and T92 steel tended to stagnate oxide layer growth over time. Oxidation kinetics were analyzed using the data of oxide layer thickness, and a regression model was presented. The regression model was significantly acceptable. The corrosion rate between the two steels through the regression model showed significant difference. The T92 steel was approximately twice as large as the time exponent and showed very good corrosion resistance compared to the T22 steel. In both steels, the oxide layer mainly formed a Fe-rich oxide layer composed of hematite (Fe₂O₃), magnetite (Fe₃O₄), and spinel (FeCr₂O₄). Sulfide segregation occurred in the oxide layer due to SO₂ gas. However, the locations of segregation for the T22 and T92 steel were different.

• 한국토양비료학회지
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• 제33권1호
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• pp.47-51
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• 2000

화합물을 분해하는 우수균주 개발의 기초연구로서, 대전 근교 지역의 논과 밭에서 채취한 토양 표품으로부터 100균주의 세균을 분리하였고, 그 중 2,4,5-T를 단일 탄소원으로 하는 고체 최소 배지에서 잘 자라는 균주 19균주를 선별하였다. 이들 균주를 등정한 결과 Pseudomonas속이 11균주 Acinetobacter속이 4균주, Alcaligenes속이 1균주이고 3균주는 미동정되었다. Pseudomonas속으로 밝혀진 MU19와 MU92는 네가지 염소계 화합물들(2,4-D, 2,4,5-T, MCPA 그리고 3CB)을 모두 분해하는 것으로 나타났다. 최소 액체배지에서 배양한 경우 Acinetobacter로 동정된 MU38균주가 접종 48시간 후에 가장 높은 분해도를 나타내었고, MUl9, MU57, MU73과 MU92는 그 다음으로 높은 분해도를 나타냈다. 실험결과 선별된 19균주 중 Acinetobacter sp. MU38 그리고 Pseudomonas sp. MU19과 MU92는 염소계 방향쪽 화합물에 대한 넓은 분해능을 갖고 있으며, 특히 2,4,5-T에 대한 높은 분해도를 나타내는 것으로 조사되었다.

• International Journal of Oral Biology
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• 제33권2호
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• pp.45-50
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• 2008

Treponema denticola is the best studied oral spirochete and numerous studies have shown that it is strongly associated with periodontitis and expresses several putative virulence factors. In this study, we report on a surface protein of T. denticola, Td92, which is homologous to Tp92 of Treponema pallidum, an agent of syphilis. Immunofluorescence assay and immunogold labeling with anti-Td92 Ab revealed that Td92 had surface-exposed epitopes. And Td92 was capable of binding to fibronectin and KB cells, an oral epithelial cell line. In addition, Td92 could enter the KB cells. These results indicate that Td92 is a fibronectin-binding protein which can bind to and internalize into the host cells, facilitating the virulence of T. denticola.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2007년도 제33회 하계학술대회 초록집
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• pp.92-92
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• 2007

• 대한금속재료학회지
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• 제47권2호
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• pp.99-106
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• 2009

The high temperature corrosion properties of heat resistant steels were investigated in oxidation atmosphere including sulfur dioxide. The heat resistant steels of T22, T92, T122, T347HFG and T304H were evaluated at 620, $670^{\circ}C$ for 400 hours. The corrosion rates showed a decreasing tendency while chrome contents of those steels increased from 2 mass.% to 19 mass.%. The in crease in temperature increasement has an more effect on the corrosion rates of low chrome steels than high chrome steels. The weight gains of T22, T92, T304H at $670^{\circ}C$ were 3.7, 1.65, 1.23 times compared with those at $620^{\circ}C$. The external scale formed on T22 was composed of hematite, magnetite and Fe-Cr spinel and internal layer including iron oxide mixed with sulfide. The scales formed on T92, T122, T304H consisted of an outer layer of hematite and inner layer of chrome oxide and hematite. The proportion of chrome oxide at inner layer was increased when the chrome contents in heat resistant steels were increased.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2007년도 The 1st International Symposium on Advanced Magnetic Materials
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• pp.92.1-92.1
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• 2007

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2007년도 춘계학술발표회 초록집
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• pp.114-115
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• 2007

The corrosion characteristics of Cr steels were investigated to protect Cr steels from the SO2-gas corrosion in the coal-fired power plant. The samples tested were low alloy ferritic steel (ASTM T22, 23), martensitic steel (ASTM T91, 92, 122), and austenitic stainless steel (ASTM 347HFG). The corrosion tests were performed between 600oC and 1000oC in Ar + (0.2, 1)%SO2 gas for 100 hr. Chromium was quite beneficial to corrosion resistance, while iron was not. The corrosion resistance increased in the order of T22, T23, T91, T92, T122, and 347HFG.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2005년도 춘계학술발표대회 개요집
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• pp.250-252
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• 2005

T/P92 steels are created for using USC boiler tube and header in next generation power plant. SP-Creep test and tensile creep test are performed to characterize creep for local structures of T/P92 steel weldment. The results are shown that P92 steel weldment is clearly superior than that of X20CrMoV121 steel weldment, which is widely used in supercritical power Plant. while fine gram HAZ is most weakest in X20 steel weldment, coarse grain HAZ is most weakest in P92.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2003년도 추계학술대회 발표논문 초록집
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• pp.92-92
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• 2003

• 한국자기학회지
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• 제4권1호
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• pp.52-55
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• 1994

HD 기체에 대하 수소 및 중수소 원자핵 스핀-격자 완화시간 $T_{1}(H)$와 $T_{1}(D)$가 측정되었다. 실험데이타는 온도 30 K < T < 313 K 및 압력 0.67 atm < P < 1.92 atm에서 측정되어졌다. 핵자기공명 주파수는 각각 수소원자핵에 대해서 358.012 MHz였고 중수소원자핵에 대해서는 54.958 MHz였다. 측정된 $T_{1}(H)$와 $T_{1}(D)$의 비로부터 분자스핀 연산자들인 $J_{z}$와 ${3J_z}^{2}-J(J+1)$에 관련된 상관시간의 비 ${\tau}_{1}/{\tau}_{2}$의 값이 얻어졌다. J = 1 상태에서의 원자핵 스핀-격자 완화시간이 온도의 함수로서 $T^{0.25}$에 비례하는 것이 관측되었다.