• Title/Summary/Keyword: P&O

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Studies on Chemical Constituents of Barley in Korea II. Relationship between protein content and P, K, Ca, or Mg among barley varieties (한국산(韓國産) 보리의 화학조성(化學組成)에 관(關)한 연구(硏究) II. 대맥품종별(大麥品種別) P, K, Ca, Mg 함량(含量)과 단백질함량(蛋白質含量)과의 관계(關係))

  • Park, Hoon;Lee, Dong-Suk
    • Korean Journal of Food Science and Technology
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    • v.7 no.2
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    • pp.82-84
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    • 1975
  • In polished barley of 22 varieties protein content was correlated significantly with MgO of $P_2O_5$ content (at p=0. 01), $K_2O$ (at p=0. 05), but it was not related to CaO. Dye binding capacity was correlated significantly (at p=0. 01) with MgO or $P_2O_5$. Thus MgO could be used for mass screening of protein content. Carbohydrate content showed insignificant negative correlation coefficients with above four minerals. There were significant positive correlation (at p=0. 01) among $P_2O_5$, $K_2O$ and MgO. The mean contents of $K_2O$, $P_2O_5$, MgO and CaO were 0. 03, 0. 29, 0. 084 and 0. 043%, respectively.

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Properties of Hydration and Strength of Sol-gol Derived Fine Particle in the System $CaO-P_2O_5-SiO_2$ (졸겔법에 의한 $CaO-P_2O_5-SiO_2$계 미세분말의 수화 및 강도특성)

  • 이형우;김정환
    • Journal of the Korean Ceramic Society
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    • v.31 no.10
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    • pp.1231-1239
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    • 1994
  • In this study, gel powder which had relatively high hydration reactivity in CaO and P2O5 rich composition of CaO-P2O5-SiO2-H2O system was prepared by sol-gel process and its hydrated specimen was manufactured. The it was investigated to appropriate calcination temperature in sol-gel process which hydrated specimen of gel powder have proven to strength and the effect of factors influenced strength in hydration process. The major product of before and after hydration reaction was hydroxyapatite, and crystalline phase of C-S-H was already formed during gelation process. After hydration reaction of pressed specimen, crystalline phase of C-S-P-H was formed. It was hydrated product of silicocarnotite (5CaO.P2O5.SiO2). Gel phases of C-S-H and C-S-P-H occured as a result of partial substitution of amorphous silica by P2O5 was formed. The strength of hydrated hardened body is developed by strong bonding and bridging between the gel phases of C-S-H or C-S-P-H and the crystalline products such as hydroxyapatite, Ca(OH)2 C-S-H and C-S-P-H. In addition, the ultrafine gel powder have an great effect on increase of hydration reaction.

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Crystallization properties of $LiO_2-P_2O_5-Bi_2O_3-V_2O_5$ Glass for cathod material (정극 재료용 $LiO_2-P_2O_5-Bi_2O_3-V_2O_5$ 유리의 결정화 특성)

  • Son, Myung-Mo;Lee, Heon-Su;Gu, Hal-Bon;Jeong, In-Seong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.05b
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    • pp.311-315
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    • 2000
  • Vanadate glass in the $LiO_2-P_2O_5-Bi_2O_3-V_2O_5$ system containing 10mol% glass fonner, $P_2O_5$ and $Bi_2O_3$ was prepared by melting the batch in pt. crucible followed by Quenching on the copper plate. We found that $LiO_2-P_2O_5-Bi_2O_3-V_2O_5$ glass-ceramics obtained from nucleation of glass showed signifieantly higher capacity and longer cycle life than conventionally made crystalline $LiV_3O_{8}$. In the present paper, we describe the charge / discharge properties during crystallization process and find the best crystallization condition of $LiO_2-P_2O_5-Bi_2O_3-V_2O_5$ glass as cathod material.

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Synthesis and Crystal Structure of $CsTiP_2O_7$ ($CsTiP_2O_7$의 합성과 결정구조)

  • 김대영;동용관;이건수;윤호섭
    • Korean Journal of Crystallography
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    • v.10 no.1
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    • pp.51-55
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    • 1999
  • Cesium titanium(III) pyrophosphate 화합물인 CsTiP2O7을 합성하고 X절 회절법을 이용하여 그 결정구조를 해석하였다. 이물질은 단사정계의 P21/a 공간군으로 결정화되었고 a=8.369(2) , b=10.208(2) , c=7.752(1) , β=104.77(2)o, V=640.4(2) 3, and Z=4이다. 이 물질의 구조는 모서리를 공유하고 있는 TiO6 팔면체와 P2O7 pyrophosphate group들로 구성된 framework로 구성되어 있으며 그 결과로 형성된 tunnel 안에는 Cs+이온이 존재한다. CsTiP2O7은 ATiP2O7(A=K, Rb)와 KAIP2O7 그리고 AMoP2O7(A=K, Rb, Cs)등 다른 +3금속 pyrophosphate들로 유사한 구조를 가지고 있다. 이 물질은 [Cs+][Ti3+][P2O74-]의 식으로 표현할 수 있다.

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Comparision of the Pressure Denaturation of Metmyoglobin in $H_2O$ and $D_2O$ ($H_2O$$D_2O$ 에서 메트미오글로빈의 압력에 의한 변성의 비교 연구)

  • Keon Kim
    • Journal of the Korean Chemical Society
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    • v.28 no.1
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    • pp.14-19
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    • 1984
  • The stability difference of metmyoglobin in $H_2O$ and $D_2O$ at pH 5.7 and pH 7.0 toward pressure denaturation is studied. Metmyoglobin is denatured in $D_2O$ at smaller pressure than in $H_2O$. The stability difference in $H_2O$ and $D_2O$ is more pronounced at pH 5.7 than at pH 7. The main reasons for the stability difference in $H_2O$ and $D_2O$are the difference in positive charge due to $H^+$and $D^+$ binding to the protein in $H_2O$ and $D_2O$, and the structural change that accompany deuteration.

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A Study on the Characteristics of Silica Fine Glass Particles prepared by Flame Hydrolysis Deposition Process (FHD법으로 형성된 실리카 유리미립자의 특성에 관한 연구)

  • Choe, Jun-Gi;Jeong, Myeong-Yeong;Choe, Tae-Gu
    • Korean Journal of Materials Research
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    • v.7 no.10
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    • pp.845-850
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    • 1997
  • 수직형 FHD증착법을 사용하여 SiO$_{2}$, SiO$_{2}$-P$_{2}$O$_{5}$, SiO$_{2}$P$_{2}$O$_{5}$-B$_{2}$O$_{3}$-GeO$_{2}$계 실리카 유리미립자를 형성하였으며, SEM, ICP-AES, XRD, TGA-DSC을 사용하여 그 특성을 분석하였다. XRD측정을 통해, 미립자 형성시 사용된 화염온도(130$0^{\circ}C$-150$0^{\circ}C$)와 기판온도(-20$0^{\circ}C$)가 SiO$_{2}$-P$_{2}$O$_{5}$계 미립자를 비정질상태로 형성하였으며, SiO$_{2}$P$_{2}$O$_{5}$-B$_{2}$O$_{3}$와 SiO$_{2}$P$_{2}$O$_{5}$-B$_{2}$O$_{3}$-GeO$_{2}$계 미립자에서는 B$_{2}$O$_{3}$, BPO$_{4}$, GeO$_{2}$의 결정성피크들을 관찰하였다. TGA-DSC 열분석을 통해, SiO$_{2}$와 SiO$_{2}$-P$_{2}$O$_{5}$는 온도변화에 따른 질량변화가 없었으며, SiO$_{2}$P$_{2}$O$_{5}$-B$_{2}$O$_{3}$-GeO$_{2}$계의 경우 질량감소를 동반한 유리전이에 따른 분자이완현상 및 결정화나 회복반응을 나타내고 있다. 질량감소는 미립자가 결정상태일때 가속되는 경향을 나타냈으며, DSC열분석을 통해 SiO$_{2}$, SiO$_{2}$-P$_{2}$O$_{5}$, SiO$_{2}$P$_{2}$O$_{5}$-B$_{2}$O$_{3}$-GeO$_{2}$계 유리미립자들의 고밀화가 시작되는 온도를 각각 1224$^{\circ}C$, 1151$^{\circ}C$, 953$^{\circ}C$, 113$0^{\circ}C$에서 관찰하였다.

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A Study on the Constituents from the Roots of Polygala tenuifolia (원지(Polygala tenuifolia WILLD.) 뿌리의 성분연구)

  • Lee, Young-Sun;Lee, Je-Hyun;Kim, Chung-Sook;Kim, Jin-Sook
    • Korean Journal of Pharmacognosy
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    • v.30 no.2
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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.

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Effect Of $Al_2O_3$on the Crystallization Of MgO-CaO-${SiO_2}-{P_2O_5}$ Bioglass-Ceramic System (I) (MgO-CaO-${SiO_2}-{P_2O_5}$계 Bioglass-Ceramic의 결정화에 미치는 $Al_2O_3$ 첨가의 영향(I))

  • 이민호;배태성
    • Journal of Biomedical Engineering Research
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    • v.15 no.2
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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.

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Fabrication and Characteristics of $Al_2O_{3p}$/AC8A Composites by Pressureless Infiltration Process (무가압함침법에 의한 $Al_2O_{3p}$/AC8A 복합재료의 제조 및 특성)

  • 김재동;고성위;정해용
    • Composites Research
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    • v.13 no.6
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    • pp.1-8
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    • 2000
  • The fabrication Process of $Al_2O_{3p}$/AC8A composites by pressureless infiltration technique and the effects of additive Mg content and volume fraction of particulate reinforcement on mechanical and wear properties were investigated. It was found that the bending strength decreased with increasing volume fraction of $Al_2O_{3p}$ particles. Whereas hardness increased with volume fraction of $Al_2O_{3p}$ particles. The decrement of strength in case of high volume fraction of $Al_2O_{3p}$ particles was attributed to high porosity level. In terms of additive Mg content, $Al_2O_{3p}$/AC8A composites containing around 5~7wt% of additive Mg indicated the highest strength, and hardness values increased with additive Mg contents. Wear resistance of AC8A alloy were improved by reinforcement of $Al_2O_{3p}$ particles especially at high sliding velocity. Wear property of $Al_2O_{3p}$/AC8A composites and AC8A alloy exhibited different aspects. $Al_2O_{3p}$/AC8A composites indicated more wear loss than AC8A alloy at slow velocity region. However a transition point of wear loss was found at middle velocity region which shows the minimum wear loss and wear loss at high velocity region exhibited almost same value as at slow velocity region, whereas wear loss of AC8A alloy almost linearly increased with sliding velocity. It was found that $Al_2O_{3p}$/AC8A composites containing $Al_2O_{3p}$ volume fraction of 20% exhibited abrasive wear surface regardless of sliding velocity and $Al_2O_{3p}$/AC8A composites containing $Al_2O_{3p}$ volume fraction of 40% showed slightly adhesive wear surface at low sliding velocity, and it progressed to severe wear as increasing the sliding velocity.

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