• 한국세라믹학회지
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• 제31권5호
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• pp.505-512
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• 1994

It has been reported that a biocement obtained by mixing CaO-SiO2-P2O5 glass powder and ammonium phosphate solution has biocompatibility as well as high strength. However, the compositional dependence on its hardening and hydroxyapatite formation phenomena has not been studied. Therefore, the main objective of this work is to study the effects of P2O5, MgO in CaO-SiO2 system glass on the hardening and hydroxyapatite formation. When more than 50 mole% of CaO containing CaO-SiO2 glasses was reacted with ammonium phosphate solution, CaNH4PO4.H2O crystal was formed, but the glass with less than 50 mol% of CaO formed (NH4)2HPO4 and NH4H2PO4 crystals which are derived from ammonium phosphate solution without reacting with the glasses. As the amount of P2O5 in CaO-SiO2-P2O5 glass system was increased, the formation of CaNH4PO4.H2O crystal was enhanced. When those hardened samples were reacted with tris-buffer solution, hydroxyapatite was obtained only for the sample with CaNH4PO4.H2O. While the substitution of MgO for CaO decreased the formation of CaNH4PO4.H2O crystal. MgNH4PO4.H2O crystla was formed in high MgO containing glass, which did not react with tris-buffer solution.

• 한국세라믹학회지
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• 제44권9호
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• pp.483-488
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• 2007

The influence of $P_2O_5$ on clinker mineral composition and the cement quality was investigated. When the sewage sludge was used as a raw material in place of clay, the presence of $P_2O_5$ in sewage sludge affects the mineral composition and the clinker quality. As the $P_2O_5$ concentration in raw mix increases, the burnability of clinker becomes worse and the alite decomposes into belite and free-CaO, so belite increases with the decrease of alite. The early strength of mortar decreases with the increase of $P_2O_5$ concentration. On the other hand, later-age strength increases with the increase of belite content. The setting time of cement was delayed with the $P_2O_5$ concentration above 0.6 wt%.

• 한국세라믹학회지
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• 제26권4호
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• pp.559-567
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• 1989

Bioglasses have been known to be as one of the promising biomateials, which can be used for replacing defective hard and soft tissue. There have been many reports on biological results for this type of glass, but no systematic work has carried out on the structures and properties of the bioglass itself. In the present study, the effect of P2O5 in bioglasses on their structures and properties was examined. Infrared and Raman spectroscopy for the glass structural analysis, differential thermal and X-ray diffraction analysis for the crystallization of the bioglass were performed, and several physical properties were measured. When the glasses were heat-treated, Na2O.2CaO.3SiO2 was the major crystalline phase and $\beta$-NaCaPO4 crystal was found for the glass with high P2O5 content. The added P2O5 in the glasses enhanced the polymerization of silicate glass structure and it changed the chain-like glass structure to a sheet-like structure, and some P2O5 may stay as phosphate monomer. With addition of P2O5 in the glass the density of the glasses decreased, but not much changes in their thermal expansion coefficient, softening point and microhardness were observed.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2000년도 춘계총회,특별강연,심포지움,연구발표회
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• pp.81.1-81.1
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• 2000

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.206-207
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• 2005

Display 소재로서 유전체나 격벽재 실링재로 사용되고 있는 frit는 PbO를 주성분으로 갖는 유리가 사용되고 있다. PbO 성분이 함유된(50$\sim$85%) 구성소재는 최근 RoHS 나 WEEE 등의 환경규제 실행에 직면해 있으며, 대체재료의 개발을 위한 많은 연구가 진행되고 있다 PbO 성분을 대체할 성분으로는 $Bi_2O_3$ 계, BaO-ZnO 계, $P_2O_5$ 계 등의 성분이 주요성분으로 이루어져 있으며, PbO 성분을 함유한 유리의 저융점, 저유전율, 고 투과율, 내산성, 내전압, 팽창계수 matching 등의 특성들에 부합되는 재료를 개발하기 위해 많은 노력을 기울이고 있다. 본 연구에서는 SnO-$P_2O_5$ 계 유리 조성을 선택하여 $R_2O_3$의 치환 및 용융분위기의 조절에 따른 저융점 유리로서의 특성과 효과에 대하여 고찰하였다.

• 한국초지조사료학회지
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• 제16권2호
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• pp.133-138
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• 1996

To investigate the effects of inorganic phosphate ($P_2O_5$ 200kg/ha), fermented cow manures($P_2O_5$ 200kg/ha, 400kg/ha) and poultry manures($P_2O_5$ 200kg/ha, 400kg/na) levels mixed with sawdust on the soil changes and productivity of alfalfa monoculture, a field experiment arranged by randonmized complete block design was conducted at National Livestock Research Institute in Suwon, September, 1993 to December 1995. The results are as follows. S1. Soil pH was changed from 5.40(before experiment) to 6.17(fermented cow manure, $P_2O_5$ 400kg/ha), 6.76 (fermented poultry manure, $P_2O_5$400kg/ha) and 6.3l(inorganic phosphate, $P_2O_5$ 200kg/ha) at 0~5cm depth of subsoil, respectively. Organic contents after experiment were lower as a range of 2.41%~3.15% than those before experiment. 2. Total nitrogen contents of each treatment showed as 0.13%~0.16% at 0~5cm depth of subsoil comparing with before experiment(0.15%). Available phosphate content of inorganic phosphate($P_2O_5$200kgha) was highest as 405ppm. lowest as 125ppm(fermented poultry manure, $P_2O_5$ 200kg/ha) than before trial(205ppm). 3. K and Ca contents of after experiment were appeared to 0.22%~0.78% and 6.45%~9.45% comparing with before experiment(0.10% and 3.56%), respectively. 4. During two years, average DM yield of fermented cow rnanure($P_2O_5$ 400kg/ha) was highest as 11, 731kg/ha and lowest as 9, 017kg/ha at fermented poultry manure plot($P_2O_5$ 200kg/ha) with as sawdust, but no significant difference was found among treatment(P>0.05). 5. CP production, NEL and TDN yield of fermented cow manure($P_2O_5$ 400kg/ha) were highest as 2, 282kg/ha 69, 900kg/ha and 6, 392kg/ha, respectively, but no significant difference among treatment(P>0.05). 6. In inorganic contents of alfalfas, there was not show same tendency in accordance with treatments. As a results mentioned above, it was possible to use 200kg $P_2O_5/ha$ of fermented cow or poultry manure with sawdust instead of inorganic phosphae fertilizer.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2000년도 추계학술발표강연 및 논문개요집
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• pp.149-149
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• 2000

• 한국결정성장학회지
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• 제1권2호
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• pp.94-103
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• 1991

ZnO함량이 45~60mol%인 ZnO-$P_2O_5$계 유리를 $1200^{\circ}C$에서 용융한 후 열처리하여 결정화시켰다. 기초유리와 결정화시킨 시료의 기계적 성질, 전기적 성질 등을 X선 회절, FTIR, 밀도, 열팽창, 전기전도도, 미세경도 등을 측정하여 검토하였다. X선 회절분석 결과 ZnO의 함량이 45~55mol%인 결정화 유리에서는 주결정상이 메타인산아연[$Zn(PO_3)_2$]이었으며ZnO가 60mol%인 시료는 피로인산아연($Zn_2P_2O_7$)으로 나타났다. 열팽창계수와 직류전기전도도는 ZnO가 50~60mol%인 시료에서 결정상 방향에 따라 각기 다른 값을 나타났으며 이는 배향성 결정상이 존재함을 시사한다.

• 공업화학
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• 제16권1호
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• pp.45-51
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• 2005

Aluminum nitrate 수용액을 원료로 사용하여 $K_2O-Li_2O-Al_2O_3$ 3성분계로부터 $K^+-{\beta}^{{\prime}{\prime}}-Al_2O_3$를 합성하였다. 순수한 $K^+-{\beta}^{{\prime}{\prime}}-Al_2O_3$의 합성을 위하여 원료물질은 $0.84K_2O{\cdot}0.082Li_2O{\cdot}5.2Al_2O_3$의 조성으로 액상상태에서 혼합되었다. 입자크기를 최소화하고 순수한 $K^+-{\beta}^{{\prime}{\prime}}-Al_2O_3$를 합성하는데 있어서 분산첨가제와 용액의 pH의 영향을 조사하였다. 분산첨가제로써 에탄올을 0.0~4.0 M 첨가하였고 용액의 pH는 $NH_4OH$ 수용액과 $HNO_3$를 이용하여 조절하였다. 시료는 pH 1.0에서 7.5까지 0.5 간격으로 수집하였다. 각 시료들은 $1200^{\circ}C$에서 2 h 동안 하소한 후 XRD와 PSA 분석을 하였다. 용액의 pH는 입자크기와 상형성에 모두 중요한 영향을 미친 반면, 에탄올의 첨가는 입자크기에만 영향을 주었다. pH 조절에 $HNO_3$를 사용하였을 경우, $HNO_3$를 사용하지 않았을 때 보다 순수한 $K^+-{\beta}^{{\prime}{\prime}}-Al_2O_3$ 상을 합성하는데 유리함을 알 수 있었다.

• 농업과학연구
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• 제44권2호
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• pp.211-220
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• 2017

We conducted this study to determine the recommended application rate of fertilizer for Houttuynia cordata Thunb cultivation. The effects of various application levels of N, $P_2O_5$, and $K_2O$ fertilizers on the growth of this plant were investigated and the associated changes in soil properties were evaluated in the field. Soil pH at harvest time of Houttuynia cordata Thunb did not differ from that before fertilization, whereas EC tended to decrease during cultivation. The soil organic matter (SOM) and available phosphorus increased after treatment, and the amount of applied fertilizer ($P_2O_5$) and available phosphorus were proportional. The nitrogen absorption amount increased in N 100% treatment, but decreased in N 150% treatment. The phosphorus absorption amount rose with the fertilizer treatment concentration until $P_2O_5$ 150% treatment. The amount of absorbed potassium decreased in treatments with $K_2O$ 150% and $K_2O$ 200%. The plant length was the longest in N 100%, $P_2O_5$ 150%, and $K_2O$ 200%. The stem diameter was estimated to be 3.46 - 3.67 mm in N 100 - 200% treatment, 3.55 - 3.67 mm in $P_2O_5$ 100 - 150%, and 3.79 mm in $K_2O$ 200%. The number of tillers did not differ amongst fertilization treatments. The fresh weight was summed to be 3.67 ton/10 a in N 100% treatment, 3.79 Mg/10 a in $P_2O_5$ 150%, and 3.83 Mg/10 a in $K_2O$ 150%. Thus, the relationship between the fertilizer amount and yields of the plant showed that the most economical quantity of fertilizers should be 10.2 N kg/10 a, 5.5 $P_2O_5$ kg/10 a, and 8.2 $K_2O$ kg/10 a for Houttuynia Cordata Thunb.