• 대한화학회지
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• 제37권1호
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• pp.172-177
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• 1993

• Bulletin of the Korean Chemical Society
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• 제29권12호
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• pp.2509-2512
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• 2008

• Bulletin of the Korean Chemical Society
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• 제27권1호
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• pp.143-146
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• 2006

• Bulletin of the Korean Chemical Society
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• 제13권1호
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• pp.8-9
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• 1992

• 대한화학회지
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• 제19권1호
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• pp.43-49
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• 1975

소량의 요오드 화합물이 윤활류에 함유될 때 금속표면사이의 마찰을 감소시키고 내마모성을 향상시키는데 이는 금속표면에 박층상구조의 이요오드화물이 형성되기 때문이라고 한다. 그러나 금속표면에서의 화학반응성, 마모와 극압실험 및 hot wire method에 의한 결과에 의하면 윤활기구는 이 요오드화물의 박층상 구조가 아니고 다른 기구에 의한 것임을 알았다. 유기 요오드화합물중에서 특히 N-iodopyridinium dichlorodate는 double charge transfer complex로써 다른 methyl iodide계의 화합물 보다 금속표면 사이의 마찰을 더욱 감소시키고 윤활기구는 interhalogen의 화학반응에 의한 것임을 알았다.

• 한국결정성장학회지
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• 제20권2호
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• pp.80-84
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• 2010

The temperature-programmed reduction of titanium oxide ($TiO_2$) with pure $CH_4$ was used for the preparation of titanium carbide crystallites. The synthesized materials had the different surface areas, indicating that the structural properties of these materials were strong functions of two different heating rates and space velocity employed. The titanium carbide crystallites were active for $NH_3$ decomposition. Since the reactivity varied with changes in the particle size, ammonia decomposition reactivity over the titanium carbides crystallites appeared to be related to the different active species. The reactivities of titanium carbide crystallites were two and three times lower than those of the vanadium and molybdenum carbide crystallites, respectively. These results suggested that the difference in activities might be related to the degree of electron transfer between metals and carbon.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.13-18
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• 2003

The concrete structure can be easily damaged due to alkali-aggregate reaction. The alkali-aggregate reaction is a reaction between the alkalies(K or Na) in cement and an unstable mineral of the aggregates. There are several test methods to identify alkali reactivity of aggregates. In general, crushed stones are tested by petrographic examination, chemical method and 모르타르 바 method. This study tested alkali-aggregate reactivity of crushed stones that has different rock types such as granitic, volcanic, metamorphic and sedimentary rocks. Samples are collected from 12 local aggregate production companies. Alkali-reactivity of various rock types was evaluated by using ASTM C 227 and C 1260, and compared the test results of two test methods.

• 한국수소및신에너지학회논문집
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• 제22권6호
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• pp.884-894
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• 2011

Effects of temperature, volatile content, particle diameter and solid input weight were investigated in the batch fluidized bed reactor using OCN703-1100 particle as oxygen carrier and Roto coal and char as fuels. Two solid fuels represented the best reactivity at different temperature, $900^{\circ}C$ for Roto coal and $950^{\circ}C$ for char, respectively. However, we selected $900^{\circ}C$ as the best operating temperature because the improvement of reactivity of char at $950^{\circ}C$ was negligible. Char represented better reactivity than Roto coal because char contains low volatile than Roto coal. For both solid fuels, reactivities were improved with increasing of the particle diameter. These results were explained by solid mixing tests in a transparent fluidized bed using two char particles having different particle size ranges and OCN703-1100 particle. The bigger particle showed better solid mixing with OCN703-1100 particle, and therefore, represented better reactivity. For both solid fuels, reactivities were improved with increasing of the solid input weight within the experimental conditions of this study because the weight of coarse particles increased with the solid input weight increased, and therefore, these coarse particles can mix well with the oxygen carrier.

• 대한화학회지
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• 제40권9호
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• pp.630-634
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• 1996

양배추 포스포리파제 D의 기질특이성을 조사하기 위해 아실 사슬길이가 틀린 코린 인지질을 사용하여 그 반응성을 검토하였다. 선택한 아실 사슬은 포화지방산 $C_8:0,\;C_{12}:0,\;C_{16}:0,\;C_{20}:0$이었다. 이들 인지질들의 반응성은 계면활성제 Sodium dodecyl sulfate의 농도에 따라 큰 영향을 받았으며, 아실 사슬길이가 길어짐에 따라 최적 PC : SDS의 농도비는 1:1.4, 1:2.2, 1:2.5, 1:3.6으로 나타났다. 이와 함께, 효소의 최적활성을 나타내는 온도도 길이가 길어짐에 따라 20$^{\circ}C$, 30$^{\circ}C$, 35$^{\circ}C$, 45$^{\circ}C$로 크게 변화하였다. 이와는 달리 최적 pH와 $Ca^{2+}$농도는 사슬길이에 따라 큰 영향을 받지 않았다. $V_{max}$ 값은 아실 사슬의 기질이 가장 커 가수분해가 잘 일어남을 보여주었으며 사슬길이가 길어질수록 반응속도는 감소하였다.

• 대한화학회지
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• 제24권1호
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• pp.64-72
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• 1980

새로운 acrylimide로서 N-acrylylpyrrolidone을 합성하였다. N-Acrylylpyrrolidone은 N-methacrylyl-lactam과는 다르게 homopolymerization을 열적으로도 함을 관찰하였다. Styrene과 N-acrylylpyrrolidone의 공중합시 각 monomer의 reactivity ratio를 구하였다. 그 결과 생성되는 copolymer는 pyrrolidone의 음이온 중합에 적절한 acyl-lactam function을 가지고 있음을 알았다.