• 한국세라믹학회지
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• 제48권1호
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• pp.26-33
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• 2011

The glass in the system of CaO-$SiO_2-P_2O_5$ and the corresponding glass-ceramics are prepared for bone cements and the behaviors of the hardening and hydroxyapatite formation were studied for the glass and glass-ceramic powders. The glass crystallized into apatite, $\alpha$-wollastonite and $\beta$-wollastonite depending on the glass composition when they were heat-treated at $950^{\circ}C$ for 4 h. A DCPD (dicalcium phosphate dihydrate : $CaHPO_4{\cdot}2H_2O$) was developed when the prepared glass and glass-ceramic powders were mixed with 3M-$H_3PO_4$ solution. The DCPD (Ca/P=1.0) transformed to HAp (Ca/P=1.67) when the bone cement was soaked in simulated body fluid (SBF), and this HAp formation strongly depended on the releasing capacity of $Ca^{2+}$ ions from the glass and glass-ceramic cements. The glass-ceramic bone cement containing $\alpha$-wollastonite crystals showed faster transformation of DCPD to HAp than other glass-ceramics containing $\alpha$- and $\beta$-wollastonite crystals. No hydroxyapatite was observed when the glass-ceramic bone cement containing apatite crystals (36P6C) was soaked in SBF even for 1 month, because no $Ca^{2+}$ ion can be released from the stable apatite crystals.

• 한국세라믹학회지
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• 제19권4호
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• pp.275-280
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• 1982

This study was carried out to research the change of mineral phases and the characteristics (apparent specific gravity, water absorption, firing shrinkage and thermal expansion etc) of the sintered bodies composed of larnite, wollastonite and anorthite etc. in $CaO-Al_2O_3-SiO_2$ system. Test bodies were composed of the same theoretical composition as it of anorthite and fired up to $1450^{\circ}C$. Investigated the change and micro-structure of the mineral phases by XRD and SEM, the characteristics of the sintered bodies by DTA/TGA and etc. The results were as follows. 1. The sintering temperature had a higher about $60^{\circ}C$ than that of $CaO-SiO_2$ system because of coexisting $Al_2O_3$. 2. The formation and transition temperature of $\beta$-wol lastonite and $\alpha$-wollastonite were similar to the results of $CaO-SiO_2$ system. 3. The formed larnite and wollastonite were decomposed and melted at about $1260^{\circ}C$. 4. Anorthite began to be synthesized at $1140^{\circ}C$, its quantity was repidly increased according to the temperature rising.

• Membrane and Water Treatment
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• 제10권4호
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• pp.259-264
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• 2019

Cost effective clay adsorptive microfiltration membranes were synthesized to remove Cr (III) from high polluted water. Raw and calcined bentonite were mixed in order to decrease the shrinkage and also increase the porosity; then, 20 wt% of carbonate was added and the samples, named B (without carbonate) and B-Ca20 (with 20 wt% calcium carbonate) were uniaxially pressed and after sufficient drying, fired at $1100^{\circ}C$ for 3 hours. Then, physical and mechanical properties of the samples, their phase analyses and microstructure and also their ability for Cr(III) removal from high polluted water (including 1000 ppm Cr (III) ions) were studied. Results showed that the addition of calcium carbonate lead the porosity to increase to 33.5% while contrary to organic pore formers like starch, due to the formation of wollastonite, the mechanical strength not only didn't collapse but also improved to 36.77 MPa. Besides, sample B-Ca20, due to the presence of wollastonite and anorthite, could remove 99.97% of Cr (III) ions. Hence, a very economic and cost effective combination of membrane filtration and adsorption technology was achieved for water treatment which made microfiltration membranes act even better than nanofiltration ones without using any adsorptive nano particles.

• 한국토양비료학회지
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• 제19권4호
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• pp.291-296
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• 1986

수도(水稻)에서 납(pb) 흡수양상(吸收樣相) 및 흡수경감효과(吸收輕減效果)를 구명(究明)하기 위(爲)하여 토양(土壤)에 납을 0, 150, 300, 600 ppm 으로 처리(處理)하고 소석회(消石灰) 및 규회석(硅灰石)을 시용(施用)하여 pot 재배(栽培)하고 수도(水稻)의 경엽(莖葉), 현미중(玄米中) 납함량(含量) 및 흡수량(吸收量)과 pH, 칼슘, 마그네슘함량(含量)과의 관계(關係)를 조사(調査)한 결과(結果)는 다음과 같다. 1. 토양중(土壤中) 납처리농도(處理濃度)가 증가(增加)할수록 경엽(莖葉)과 현미중(玄米中) 납함량(含量) 및 흡수량(吸收量)이 증가(增加)하였으나 수량(收量)은 별영향(別影響)이 없었다. 2. 석회물질시용(石灰物質施用)으로 수도(水稻)의 납흡수억제효과(吸收抑制效果)가 인정(認定)되었다. 3. 물관리(管理)에서 수도(水稻)의 납흡수억제효과(吸收抑制效果)는 간단관수구(間斷灌水區)가 상시담수구(常時湛水區)보다 좋았다. 4. 토양중(土壤中) pb/Ca+Mg당량비(當量比)가 증가(增加)할수록 식물체중(植物體中) 납함량(含量)이 증가(增加)하였다. 5. 석회물질시용(石灰物質施用)에 따른 토양(土壤)의 pH는 소석회(消石灰)>규회석(硅灰石)>무시용(無施用)의 순(順)이었다. 6. 시험후(試驗後) 토양중(土壤中) $1N-NH_4$ OAC 가용성(可溶性) 납함량(含量)은 상시담수구(常時湛水區)가 간단관수구(間斷灌水區)보다 높았고 석회물질별(石灰物質別)로는 무시용(無施用)>규회석(硅灰石)>소석회(消石灰)의 순(順)이었다.

• Applied Biological Chemistry
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• 제14권3호
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• pp.183-189
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• 1971

규산재료(珪酸材料)인 강사(江砂) 및 석영(石英)과 농용(農用) 소석회(消石灰)의 혼합(混合) 용융물(溶融物)에 대(對)한 규산질(珪酸質) 비료(肥料)로써의 효과(效果)를 구명(究明)코져 유효규산함량(有效珪酸含量)이 낮은 답토괴(畓土壞)에서 수도(水稻)에 대(對)해서 천연(天然) 규회석(珪灰石)을 대조(對照)로 시비처리(施肥處理)하여 시험(試驗)한 결과(結果) 1. 모래용융물(溶融物)이 석영용융물(石英溶融物)에 비(比)하여 N/2 염산가용규산함량(鹽酸可溶珪酸含量)이 높고 2% 구연산 가용규산함량(可溶珪酸含量)은 석영용융물(石英溶融物)이 모래용융물(溶融物)보다 높았다. 2. 벼의 규산흡수량(珪酸吸收量)은 석영용융물(石英溶融物)에서 가장 크고 모래용융물(溶融物)과 규회석(珪灰石)은 거의 같았으며 이용율(利用率)은 천연(天然) 규회석(珪灰石)이 가장 높고 석영용융물구(石英溶融物區)가 모래용융물구(溶融物區)보다 높았다. 3. 정조수량(正租收量)은 규산물질(珪酸物質)의 시용(施用)으로 수량구성요소중(收量構成要素中) 수당입수(穗當粒數), 등숙률(登熟率) 및 천입중(千粒重)의 증가(增加)로 증수(增收)되었으며 공시재료중(供試材料中) 석영용융구(石英溶融區)에서 가장 크게 증수(增收)하였으며 대조구(對照區)${\fallingdotseq}$모래용융물(溶融物) 100kg/10a<천연규회석(天然珪灰石)${\fallingdotseq}$모래용융물(溶融物) 300kg/10a${\fallingdotseq}$석영용융물(石英溶融物) 100kg/10a<모래용융물(溶融物) 500kg/10a${\fallingdotseq}$석영용융물(石英溶融物) 300kg/10a<석영용융물(石英溶融物) 500kg/10a의 순서(順序)이었다.

• 한국토양비료학회지
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• 제19권1호
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• pp.32-37
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• 1986

벼에 대(對)한 규회석(硅灰石) 및 광재규산질비료(鑛滓珪酸質肥料)의 시용효과(施用效果)를 검토(檢討)하기 위(爲)해 유효규산함량(有效珪酸含量)이 56ppm정도(程度)인 사양토(砂壤土)에서 3년간(年間) 포장시험(圃場試驗)을 실시(實施)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 규회석(硅灰石) 및 광재규산질비료시용(鑛滓硅酸質肥料施用)은 생육초기(生育初期)에는 분얼(分蘖) 및 초장(草長)을 억제(抑制)하나 생육후기(生育後期)에는 분얼수(分蘖數)를 늘리고 초장(草長)을 길게 했었다. 2. 규회석(硅灰石) 및 광재규산질비료시용(鑛滓硅酸質肥料施用)으로 수량(收量)은 증대(增大)되었으며 규회석(硅灰石) 및 광재규산질비료(鑛滓硅酸質肥料施)를 동일량(同一量)으로 시용(施用)했을 때의 수량증대효과(收量增大效果)는 같았다. 3. 수확기(收穫期) 식물체(植物體)의 규산흡수이용율(珪酸吸收利用率)은 광재규산질비료(鑛滓硅酸質肥料) 시용(施用)보다 규회석시용(硅灰石施用)에서 더 높았다. 4. 시험후(試驗後) 토양중(土壤中) 유효규산잔존율(有效珪酸殘存率)은 규회석시용(硅灰石施用)보다 광재규산질비료(鑛滓硅酸質肥料施) 시용(施用)에서 높았다. 5. 시험후(試驗後) 토양중(土壤中)의 유효규산함량증가(有效珪酸含量增加)는 규회석(硅灰石) 및 광재규산질비료(鑛滓硅酸質肥料施)에 관계(關係)없이 0.5N-HCl 가용규산성분함량(可溶珪酸成分含量)으로 1kg/10a 시용시(施用時) 약(約) 2.3ppm 증가(增加)되었다. 6. 식물체(植物體)의 $SiO_2/N$비(比)가 클수록 목도열병(稻熱病) 이병율(罹病率)은 감소(減少)하는 경향(傾向)이었다.

• 한국토양비료학회지
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• 제20권2호
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• pp.123-129
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• 1987

수도(水稻)의 축산폐수(畜産廢水) 피해(被害)에 대한 물관리(管理) 및 개량제(改良劑) 시용효과(施用效果)를 구명(究明)하기 위하여 사양토(砂壤土)에서 2년간(年間) pot 시험(試驗)한 결과(結果)는 다음과 같다. <시험(試驗) 1> 물관리(管理) 및 개량제(改良劑) 시용효과(施用效果)(1985) 1. 수도수량(水稻收量)은 상시담수구(常時湛水區)가 간단관수구(間斷灌水區) 보다 많다고 개량제(改良劑) 시용(施用)으로 증수(增收)되는 경향(傾向)이였으며 개량제중(改良劑中) Zeolite와 규회석(硅灰石)이 효과(效果)가 좋았음. 2. 고중(藁重) 및 식물체중(植物體中) 질소함량(窒素含量)은 시용질소(施用窒素) 및 폐수관개량(廢水灌漑量)이 많을수록 증가(增加)하였으나 개량제(改良劑) 시용(施用)으로 감소(減少) 하였음. <시험(試驗) 2> 규회석(硅灰石) 시용효과(施用效果)(1986) 3. 수도수량(水稻收量)은 규회석(硅灰石) 시용량(施用量)이 증가(增加)할수록 증수(增收)되었으며 규회석시용(硅灰石施用)에 의(依)한 증수원인(增收原因)은 등숙율(登熟率) 및 수당입수(穗當粒數)의 증가(增加)에 있었고 질소시용량(窒素施用量)이 3g/pot (관행(慣行))구(區)에서는 규회석(硅灰石) 60g/pot 시용(施用)이 적량(適量)으로 생각되었다. 4. 불임수수(不稔穗數)는 시용질소(施用窒素) 및 폐수중(廢水中) 질소농도(窒素濃度)가 증가(增加)됨에 따라 증가(增加)하는 경향(傾向)이었으며 규회석시용(硅灰石施用)으로 크게 감소(減少)되었다.

• 한국세라믹학회지
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• 제11권4호
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• pp.19-24
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• 1974

The study was investigated to confirm the morphology of crystal from xonotlite to wollastonite at elevated temperature by electron microscopy. Mixtures of slaked lime and powdered quartz with plenty water were oscillated continuously in an autoclave under the pressure of 25kg/$\textrm{cm}^2$ for 8 hours to obtain well crystallized xonotlite. This milky slurry consisting of xonotlite was gained and dried in oven at 11$0^{\circ}C$. Examination of the electron micrograhs showed the xonotlite to be developed thin lath-like crystals and to be formed aggregate as chestnut bur. Details of the morphology suggest that the heat-treated xonotlite up to 100$0^{\circ}C$ splited and deformed slightly in agreement with the topotaxial transformation theory of xonotlite to wollastonite. The molded material endured in good shape under 120$0^{\circ}C$ except a little shrinkage.

• 한국세라믹학회지
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• 제14권1호
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• pp.12-18
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• 1977

In our former paper, tremolitic talc, -wollastonite-clay system was studied. In this study blast furnace slag was used(B.F.S.) instead of wollastonite for developing a fast-firing wall tile body. The wall tile bodies consisting of tremolitic talc and B.F.S. asmajor constituents have been fired in the temperature range 1000-120$0^{\circ}C$. Some of these bodies have showed good properties for wall tile manufacture. According to the increased content of B.F.S the fired bodies have showed the decreased thermal expansion which was resulted from the fact that the amounts of diopside and anorthite were gradually increased and those of quartz relatively decreased. Being reasonable in low price and thermo-stable properties tremolitic talc and B.F.S. will be good materials for the fast-firing tile body.

• Advances in concrete construction
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• 제6권2호
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• pp.123-143
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• 2018

Self compacting concrete (SCC) has good flowability, passability and segregation resistance because of voluminous cementitious material & high coarse aggregate to fine aggregate ratio, and high free water availability. But these factors make it highly susceptible to shrinkage. Fibers are known to reduce shrinkage in concrete mixes. Until now for conserving cement, only pozzolanic materials are admixed in concrete to yield a SCC. Hence, this study compares the use of wollastonite micro fiber (WMF), a cheap pozzolanic easily processed raw mineral fiber, and flyash in yielding economical SCC for rigid pavement. Microsilica was used as a complimentary material with both admixtures. Since WMF has large surface area ($827m^2/kg$), is acicular in nature; therefore its use in yielding SCC was dubious. Binary and ternary mixes were constituted for WMF and flyash, respectively. Paste mixes were tested for compatibility with superplasticizer and trials were performed on a normal concrete mix of flexural strength 4.5 MPa to yield SCC. Flexural strength test and restrained shrinkage test were performed on those mixes, which qualified self compacting criteria. Results revealed that WMF admixed pastes have high water demand, and comparable setting times to flyash mixes. Workability tests showed that 20% WMF with microsilica (5-7.5%) is efficient enough in achieving SCC and higher flexural strength than normal concrete at 90 days. Also, stress rate due to shrinkage was lesser and time duration for final strain was higher in WMF admixed SCC which encourages its use in yielding a SCC than pozzolanic materials.