• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.2224-2226
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• 2000

In this paper, we tried to figure out the residual stress of Electroless Nickel (EN) films as a function of process conditions: bath temperatures, pH values, and hypophosphorous acid concentrations. The residual stresses of EN films were in the range of - 4 MPa to 250 MPa depending on process conditions and they were very sensitive to phosphorous concentration in EN film and also hypophosphorous acid concentrations in EN bath.

• Carbon letters
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• 제15권4호
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• pp.277-281
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• 2014

A series of high capacity soft carbons with different phosphorus contents were successfully prepared by carbonizing petroleum cokes treated with hypophosphorous acid at $900^{\circ}C$. The effect of phosphorus content on the electrochemical performance of the soft carbons was extensively investigated. The P-doped soft carbons exhibited greatly enhanced discharge capacities and outstanding rate capabilities with increasing phosphorus content. In addition, the influence of temperature on the electrochemical behaviors of the soft carbons was investigated in a wide temperature range of $25^{\circ}C$ to $50^{\circ}C$. Surprisingly, the electrochemical properties of the pristine and P-doped soft carbons were highly sensitive to the operating temperature, unlike conventional graphite. The pristine and P-doped soft carbons exhibited significantly high discharge capacities of 470 and 522 mAh/g, respectively, at a high temperature of $50^{\circ}C$.

• 대한화학회지
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• 제49권2호
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• pp.129-137
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• 2005

• 한국분말재료학회지
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• 제18권3호
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• pp.244-249
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• 2011

Spherical nanosized cobalt powder with an average size of 150-400 nm was successfully prepared at room temperature from cobalt sulfate heptahydrate ($CoSO_4{\cdot}7H_2O$). Wet chemical reduction method was adopted to synthesize nano cobalt powder and hypophosphorous acid ($H_3PO_2$) was used as reduction agent. Both the HCP and the FCC Co phase were developed while $CoSO_4{\cdot}7H_2O$ concentration ranged from 0.7 M to 1.1 M. Secondary phase such as $Co(OH)_2$ and $CO_3O_4$ were also observed. Peaks for the crystalline Co phase having HCP and FCC structure crystallized as increasing the concentration of $H_3PO_2$, indicating that the amount of reduction agent was enough to reduce $Co(OH)_2$. Consequently, a homogeneous Co phase could be developed without second phase when the $H_3PO_2/CoSO_4{\cdot}7H_2O$ ratio exceeded 7.

• 생명과학회지
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• 제17권7호통권87호
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• pp.910-914
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• 2007

본 연구는 MRI 조영제나 새로운 생리활성 물질을 개발키 위해 paraformaldehyde와 hypophosphorous acid를 아미노산인 glycine 혹은 glutamic acid와 함께 반응시켜 3,7-dihydroxy-3,7-dioxoperhydro-1,5,3,7-diazadiphos-phocme-1,5-diacetic acid 1 와 3,7-dihydrexy-3,7-dioxoperhydre-1,5,3,7-diazadiphos-phocme-1,5-di- (2-glutaric acid)3을 합성하였다. 그러나 aspartic acid에 의한 2-[5-(1,2-dicarboxy-ethyl)-3,7-dihydroxy-3,7-dioxo-315.715-[1,5,3,7]diazadiphosphocan-1-yl]-succinic acid 2는 얻지 못했다. 합성 된 3,7-dihydroxy-3,7-dioxoperhydro-1,5,3,7-dia-zadiphosphocine-1,5-diacetic acid 1을 산 촉매에 의한 에스테르화반응시켜 화합물 3,7-dihydroxy-3,7-dioxoper-hydro-1,5,3,7-diazadiphosphocine-1,5-diacetic acid methyl ester 4, 3,7-dihydroxy-3,7-dioxoperhydro-1,5,3,7-dia-zadiphosphocine-1,5-diacetic acid ethyl ester 5, 그리고 3,7-dihyoxy-3,74dioxoperhyo-1,5,3,7-diazadiphosphocine-1,5-diacetic acid propyl ester 6을 합성하였다. 계속해서 다양한 반응을 통해 새로운 화합물을 합성할 것이며 생리활성검색도 실시할 예정이다.