• 마이크로전자및패키징학회지
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• 제6권4호
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• pp.55-59
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• 1999

전자 패키징에 적용 가능한 납성분이 포함되어 있지 않는 Bi계저융점유리의 연구를 행하였다. Bi계유리중, 70wt% $Bi_2O_3$+ l5wt% $B_2O_3$ + 8wt% $SiO_2$+ 2wt% $P_2O_5$ + 4wt% $A1_2O_3$ + lwt%ZnO 성분의 유리는 융점이 약 $550^{\circ}C$ 였으며, $P_2O_5$의 함량에 따라서 그 융점이 변화하였다. 10wt%이상의 $P_2O_5$ 첨가에서는 $450^{\circ}C$의 열처리로 결정화가 진행되었다. $B_2O_3$가 많이 함유된 조성의 유리에서는 그 융점이 상승하였다.

• 한국세라믹학회지
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• 제22권3호
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• pp.35-40
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• 1985

The composition of the base glass was determined to be $Na_2O$ 15, $Fe_2O_3$ 35, $B_2O_3$ 0~20, $P_2O_5$ 30~50 by mole percent. The heating temperature for nucleation was determined by means of thermal expansion curve. Crystalline phases were investigated by X-ray diffraction method and I.R Spectra. Electrical conductivities of glass spec-imens were observed in the temperature range 25~20$0^{\circ}C$ The activation energies of these specimens were caculated. The results obtained were as follows : 1) The limit composition of the melts 15mol% $Na_2O$ 35mole% $Fe_2O_5$ 20mole% $B_2O_3$ 30mole% $P_2O_5$ was able to be formed into desired shapes during cooling, . 2) In the measurement of d. c conductivity($\delta$) on the glasses in the system $15Na_2O-35Fe_2O_3$-$B_2O_3$-(50-x) $P_2O_5$ the values decreased by replacing 5 mole% $P_2O_5$ with $B_2O_3$ 3) The d. c conducties of heat treated samples were increased by replacing $P_2O_5$ with $B_2O_3$ 4) $B_2O_3$ contributed to precipitate crystals such as${\gamma}$-$Fe_2O_3$ $Fe_3O_4$ which had the advantage of electronic conduction in heat treated samples. 5) The slope plotted Log($\delta$) versus 1/T in this glass system was linear in the measured temperature range.

• 생약학회지
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• 제30권2호
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• pp.168-172
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• 1999

Five compounds were isolated from the roots of Polygala tenuifolia (Polygalaceae). On the basis of spectroscopic evidences, the structures of these compounds were characterized as ${\alpha}-D-(6-O-sinapoyl)-glucopyranosyl(1{\rightarrow}2')-{\beta}-D-(3'-O-sinapoyl)-fructofuranoside$ (P3), ${\alpha}$-D-{6-O-(p-methoxybenzoyl)}-glucopyranosyl-$(1{\rightarrow}2')$-${\beta}$-D-{3'-O-(3',4',5'-trimethoxycinnamoyl)}-fructofuranoside(P4), ${\alpha}$-D-{6-O-(p-hydroxybenzoyl)}-glucopyranosyl-$(1{\rightarrow}2')$-${\beta}$-D-{3'-O-(3',4',5'-trimethoxycinnamoyl)}-fructofuranoside(P5), ${\alpha}-D-glucopyranosyl-(1{\rightarrow}2')-{\beta}-D-(1'-O-sinapoyl)-fructofuranoside$(P6), $1,5-anhydro-D-glucitol$(P7) respectively. ${\alpha}$-D-{6-O-(p-Methoxybenzoyl)}-glucopyranosyl-$(1{\rightarrow}2')$-${\beta}$-D-{3'-O-(3',4',5'-trimethoxycinnamoyl)}-fructofuranoside(P4) and ${\alpha}-D-glucopyranosyl-(1{\rightarrow}2')-{\beta}-D-(1'-O-sinapoyl)-fructofuranoside$(P6) were isolated for the first time from the genus of Polygala. 1,5-Anhydro-D-glucitol(P7) was isolated without hydrolysis for the first time from the root of Polygala tenuifolia.

• 대한의용생체공학회:의공학회지
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• 제15권2호
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• pp.189-194
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• 1994

Effects of ${AI_2O_3}/{P_2O_5}$ ratio on the crystallization of a series of glasses with the nominal composition of 41.4wt % $SiO_2$, 35.0wt % CaO, 20.6wt % (${P_2O_5}$+${AI_2O_3}$) and 3.0wt% MgO were investigated with DTA, XRD and SEM. The major crystalline phases are apatite and anorthite. The glass transition temperature ($T_g$) and the softening point ($T_s$) are shifted to the upper temperature by increasing $AI_2O_3$ content. The temperature of apatite crystallization ($T_{p1}$) is increased by $AI_2O_3$ content, but the tempera¬ture of anorthite crystallization ($T_{p2}$) is not affected significantly. With increased of $AI_2O_3$, the apatite crystallization is decreased, but anorthite crystallization is increased.

• 한국산학기술학회논문지
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• 제11권2호
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• pp.604-607
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• 2010

$P_2O_5-K_2O$-FeO-CuO계 유리의 형성및 이온용출에 대하여 연구하였다. $P_2O_5$를 60mol%로 고정하고 $K_2O$-FeO-CuO의 mol%를 10mol%에서 40mol%까지 변화를 주었다 제조된 유리시편을 증류수에서 13시간 동안 침적시키며 2시간 간격으로 용출 특성을 평가 하였다. 초기 유리구조 내 Phosphate의 $P_2O_5$가 1차 용출이 일어나며 2차로 염기성 산화물의 용출이 일어나면서 Cu, Fe 이온이 함께 용출되는 것으로 관찰되엇다. ICP 관찰시에는 유리의 형성 구조의 차이에 따라 용출량이 변화 하였고, 용출은 $10K_2O$(mol%)함량일 때 CuO와 FeO의 용출량이 가장 많이 일어나는 것으로 관찰되었다.

• 한국세라믹학회지
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• 제45권8호
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• pp.459-463
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• 2008

$P_2O_5-SnO_2$ system $0.5SnO_2-xP_2O_5-(0.5-x)B_2O_3$(x=0.1, 0.2, 0.3, 0.4, 0.5) glasses have been prepared for Pb-free low temperature glass frit. A investigation about the effect of $B_2O_3$ substitution on properties of $P_2O_5$ glasses, including glass structure properties, thermal properties, and mechanical properties was presented. Substance that is responsible for in moisture absorption existing circumstances supposes by phosphate, and excess moisture tolerance that state funeral's structure is improved breaking does not affect in state funeral bond that only most single bond remains, and can know that does not suffer big impact in boric oxide anomaly present state. This phenomenon estimates that connect with structure change. It is thought according to link this result the phosphoric acid happened structural change. $B_2O_3$ displacement quantity 0.3 mole put out $BO_4$ structures, but above 0.3 mole it changed with the case $BO_3$ structure which it displaces.

• 한국세라믹학회지
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• 제30권6호
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• pp.433-440
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• 1993

The bioactivity of glasses in the CaO-SiO2 system and CaO-P2O5-SiO2 system with less than 10mol% of P2O5 was investigated by in vitro test in simulated body flood(SBF). The formation of Ca.P film and hydroxyapatite on the surface of glasses after in vitro test was analysed by X-ray photoelectron spectoscopy (XPS), fourier transform infrared reflection spectroscopy (FT-IRRS), energy dispersive X-ray spectroscopy (EDS), and scanning electron microscopy (SEM) observation. In the early stage of Ca.P film formation after in vitro test for CaO-SiO2 and CaO-P2O5-SiO2 glasses, the rate of Ca.P film formation on the surface of the glasses was dependent of structural parameter (Y) evaluated from the glass composition. First, in the case of the glasses having Y value below 2, Ca.P film and SiO2-rich layer were formed simultaneously, and there were no differences of the rate of Ca.P film formation in terms of the Y values. Second, in the case of the glasses having Y value above 2, the SiO2-rich layer was formed, and then Ca.P.Si mixed layer was formed in the silica gel structure of the SiO2-rich layer, and finally the Ca.P film on the surface of SiO2-rich layer. The rate of Ca.P film formation delayed as the Y values increased. The rate of hydroxyapatite formation of glasses (the rate of transformation from Ca.P film to hydroxyapatite) seems to be propotional to the rate of Ca.P film formation and Y value. The rate of hydroxyapatite formation of glasses belonging to the second group was delayed as structural parameter increased, and the hydroxyapatite crystal showed spherical growth in the early reaction stage, and then showed silkworm-like linear growth as the reaction time increased.

• 한국결정성장학회지
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• 제21권5호
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• pp.210-213
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• 2011

$P_2O_5$ 함량에 따른 $5Na_2O-36CaO-10TiO_2-xP_2O_5$으로 구성된 glass-ceramic을 다음과 같은 방법으로 제조하였다: 1) 1 N HCl 용액 내에서 $Ca_3(PO_4)_2$와 $NaTi_2(PO_4)_3$ 간의 $Ca_3(PO_4)_2$ 결정을 2일간 추출하여 제거함. 2) Ag($NO_3$) 용액에서 1일간 $Na^+$ 이온을 $Ag^+$ 이온으로 이온 교환시킴. Glass-ceramic의 합성 여부를 SEM 및 XRD를 이용하여 확인하였다. Staphylococus aureus를 이용한 박테리아 실험 결과 3시간 이후에는 완전하게 박테리아가 제거됨을 확인할 수 있었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.383-386
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• 1999

The importance of rechargeable lithium cells has been emphasized. So a large variety of materials has been discovered and evaluated for use as reversible cathodes and electroyltes. This paper examines the charge/discharge properties and the charge/discharge cycling life of Li$_2$O-P$_2$O-V$_2$O$_{5}$Li cells. In audition, DTA tests were carried out on Li$_2$O-P$_2$O-V$_2$O$_{5}$ glass. As a result the best performance was achieved when 0.3Li$_2$O-0.1P$_2$O$_{5}$-0.6V$_2$O$_{5}$Li cells was mixed with SP270. that is discharge capacity of 240mAh/g have been achieved. In addition this battery exhibited good cycling performance. Considering these results we expected utilization of the Li$_2$O-P$_2$O-V$_2$O$_{5}$ glass as a cathode material in a secondary battery.y battery.

• 대한화학회지
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• 제28권1호
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• pp.14-19
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• 1984

메트미오글로빈의 압력에 의한 변성의 $H_2O$와 $D_2O$에서의 차이를 pH 5.7과 pH 7.0에서 연구하였다. 메트미오글로빈은 $D_2O$에서 $H_2O$보다 더 작은 압력에서 변성하였다. 그 차이가 pH 5.7에서가 pH 7에서 보다 더 컸다. $H_2O$와 $D_2O$에서 이 안정도의 차이가 단백질에 대한 $H^+$와 $D^+$의 결합에 차이가 있기 때문이며 또한, 수소가 중수소로 바뀜에 따르는 구조 변화 때문인 것으로 사료된다.