• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.336-340
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• 1999

This study was performed to evaluate the physical properties of reinforced soil-mixture powder. Soil was used to be powder that passed by the No. 200 mech and the reinforcement as calcium carbonate, quicklime and portland cement used for this study to improve soil. We resulted from fineness , setting time, and compressive strength test of reinforced soil-mixture powder. We've got the two conclusions . The first , in case that we were used reinforced soil-mixture powder included some portland cement, the higher the mixture rates of the reinforcement , the wider the difference theoretical data with experimental data. The second, the setting time of reinforced soil-mixture powder is faster than soil powder itself and the reinforcement for promoting strength was proved that calcium carbonate was proper than others if we compared it with other reinforcment.

• Restorative Dentistry and Endodontics
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• 제10권1호
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• pp.31-42
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• 1984

The toxic effect of adhesive resins on the dog's pulp tissue was studied with 70 teeth from 5 dogs. The experimental materials were Clearfil, a mixture of Clearfil with calcium hydroxide powder, Panavia-EX, and a mixture of Panavia-EX with calcium hydroxide powder. As a control group, calcium hydroxide powder was used. Each material was placed on the pulpotomized tissue surface. After 3 days, 1, 2,4, and 6 weeks, the teeth and apical tissue were processed routinly and stained with hematoxylin and eosin. Pathological tissue changes due to the toxicity of adhesive resins were observed by light microscope, and the pH of Panavia-EX and the Bonding agent of Clearfil were measured. Following were the results; 1. In the group of calcium hydroxide powder, slight inflammatory change was observed in the pulpotomized surface and adjacent pulp tissue on 3 day. 1 week case showed incomplete dentin bridge. The remaining pulp tissue was normalized according to the days elapsed. 2. In the group of Clearfil, early inflammatory change revealed in the superificial portion of the remaining pulp tissue on 3 day. The inflammation spreaded over the total pulp tissue and partial necrosis was observed in 1 week and 2 week cases. Total necrosis of pulp tissue and moderate inflammatory change at the apical tissue was noticed in 4 week and 6 week cases. 3. In the group of Panavia-EX, moderate inflammatory change appeared in the superficial pulp tissue on 3 day, and severe inflammatory change over all pulp tissue found in 1 week case. Pulp necrosis was obvious in 2 week case. 4 week and 6 week cases were totally necrotized up to the periapical tissue. 4. In the groups of mixtures with calcium hydroxide powder, the pulp tissue destruction was retarded, compared with the groups of Clearfil and Panavia-EX. 5. Panavia-EX was more destructive than Clearfil. 6. The acidity of freshly mixed Bonding agent of Cleafil was pH 4.0, and that of Panavia-EX was pH 2.0.

• Environmental Engineering Research
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• 제21권4호
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• pp.341-349
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• 2016

To improve the utilization rate of construction waste as mine backfilling materials, this paper investigated the feasibility of using recycled powder as mine paste backfilling cementitious material, and studied the pozzolanic activity of recycled construction waste powder. In this study, alkali-calcium-sulfur served as the activation principle and an orthogonal test plan was performed to analyze the impact of the early strength agent, quick lime, and gypsum on the pozzolanic activity of the recycled powder. Our results indicated that in descending order, early strength agent > quick lime > gypsum affected the strength of the backfilling paste with recycled powder as a cementitious material during early phases. The strength during late phases was affected by, in descending order, quick lime > gypsum > early strength agent. Using setting time and early compressive strength as an analysis index as well as an extreme difference analysis, it was found that the optimal ratio of recycled powder cementitious material for mine paste backfilling was recycled powder:quick lime:gypsum:early strength agent at 78%:10%:8%:4%. X-ray diffraction analysis and scanning electron microscope were used to show that the hydration products of recycled powder cementitious material at the initial stages were mainly CH and ettringite. As hydration time increased, more and more recycled powder was activated. It mainly became calcium silicate hydrate, calcium aluminate hydrate, etc. In summary, recycled powder exhibited potential pozzolanic activities. When activated, it could replace cementitious materials to be used in mine backfill.

• 한국식품영양과학회지
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• 제35권7호
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• pp.853-859
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• 2006

본 연구는 난각 칼슘염의 종류와 난막의 존재유무가 칼슘대사에 미치는 영향을 알아보기 위하여 난각에서 탄산칼슘을 용해시켜 난각 칼슘유무에 따른 칼슘급원으로서의 생기적 유용성을 확인하여 경제적이고 효과적인 칼슘보충제를 개발하고자 본 연구를 실시하였다. 실험동물은 4주령의 Sprague-Dawley종 수컷 흰쥐를 사용하였으며 실험식이는 난각분을 유기산에 용해시켜 제조한 난각 칼슘염(초산염, 글루쿠론산염)과 난각분을 각각 난막 분리와 난막 미분리로 나누어 급여하였다. 1군은 난막 미분리 난각분{ES(M+)}을, 2군에게는 난막 분리 난각분{ES(M+)}을, 3군에게는 난막 미분리 초산염{AC(M+)}을, 4군에게는 난막 분리 초산염{AC(M-)}을, 5군에게는 난막 미분리 글루쿠론산염{GC(M+)}을, 6군에게는 난막 분리 글루쿠론산염{GC(M-)}을 칼슘농도 0.2%로 조정하여 4주간 급여하여 사육하였다. 칼슘염 중 초산염이 글루쿠론산염보다 대퇴골의 무게를 향상시켰으며 난막존재시 대퇴골 무게가 다소 증가하는 경향을 보였다. 그러나 난각 칼슘염의 종류와 난막유무에 따른 interaction은 없었다. 대퇴골의 체중 100 g당 Ca함량은 난막 미분리군에서는 난각 칼슘염의 종류에 따른 유의적인 차이를 보였으며, 체중 100 g당 대퇴골의 Ca함량은 난막 미분리군에서는 글루쿠론산염군에서 가장 높은 수준이었으며, 난막 분리군에서는 초산염군으로 나타났다. 난막 분리군에서는 난각 칼슘염간의 유의적인 차이는 없었으나 칼슘염이 난각 분말 형태에 비해 높은 경향을 보였다. Ca 흡수율과 보유량은 난막 미분리군에서는 GC(M+)>AC(M+)>ES(M+)의 순서였으며 난막 분리군에서는 AC(M-)ES(M-)의 순으로 난막분말 형태보다는 난각 칼슘염의 형태에서 높은 수준을 보여 난각 칼슘염의 형태가 Ca 흡수율과 보유량을 상승시키는 것으로 나타났다. ALP의 활성은 난막유무에 관계없이 각군 간에는 유의적인 차이는 없었느나 글루쿠론산염의 형태가 가장 높은 활성을 보인 반면 초산염의 형태가 가장 낮은 경향을 보였다. 이상의 결과들을 미루어 볼 때 난각분으로 공급하기보다는 난각 칼슘염 형태로 공급하는 것이 칼슘대사에 유리하게 작용하는 것으로 사료된다. 따라서 난각의 $CaCO_3$를 이온화하여 칼슘급원으로 공급하거나 다양한 식품에 첨가하여 기능성을 부가한 건강증진 제품으로 개발하는 것은 한국인의 칼슘섭취수준을 향상시키고 칼슘부족으로 인한 질병예방 및 개선에 도움이 될 뿐만 아니라 폐자원으로부터 고부가가치제품을 개발함으로써 농가 소득 및 국가경제 향상에 기여할 수 있을 것으로 사료된다.

• 한국구조물진단유지관리공학회 논문집
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• 제24권2호
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• pp.86-93
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• 2020

숏크리트용 콘크리트는 일반적으로 1종 보통 포틀랜드시멘트(이하 OPC)를 100% 사용한 레미콘 제품에 현장에서 별도로 숏크리트용 급결제를 약 5% 혼합하는 방식으로 사용된다. 본 연구에서는 국내에서 사용률이 높은 시멘트 광물계 급결제(calcium aluminate)를 사용한 숏크리트용 결합재로서 기존 OPC에 슬래그분말(이하 SP), 석회석분말(이하 LSP)를 첨가하여 혼합시멘트를 사용할 때의 응결 및 압축강도, 페이스트 수화물 및 공극구조에 미치는 영향을 시험 및 분석하여 재령별 수화물의 생성량과 공극구조가 숏크리트의 모르타르 성능에 미치는 영향을 파악하였다. 향후 숏크리트용 결합재로서 최적화된 결합재를 제조하는데 활용할 수 있을 것으로 기대된다.

• 한국지역사회생활과학회지
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• 제18권1호
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• pp.55-62
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• 2007

본 연구는 표고버섯에 많이 함유된 ergosterol을 비타민 D로 전환시킨 표고버섯 분말을 메밀 냉면에 첨가함으로써 우리 국민의 골격 건강에 도움을 줄 수 있는 건강편의식을 개발하기 위한 것이다. 표고버섯 분말의 활용성을 조사하기 위하여 제조한 냉면의 종류는 기본 메밀 냉면 외에 3% 표고버섯분말 첨가냉면, 5% 표고버섯분말 및 해조칼슘 첨가 냉면, 3% 표고버섯 분말 및 해조칼슘 첨가 냉면 등 총 5종이었다. 표고버섯 분말은 총 반죽 무게의 3%와 5% 수준으로 첨가하였고, 해조칼슘의 첨가량은 냉면 1회 분량 당 1.4g의 칼슘이 함유되도록 하였다. 냉면의 질감에 대한 기계적 측정 결과, 버섯분말 혹은 해조칼슘 첨가로 인해 조리면의 경도, 응집성, 검성 및 탄력성 등은 영향을 받지 않는 것으로 나타났다. 접착성은 3% 버섯분말첨가 냉면에서만 약하게 나타났으며, 씸힘성은 특히 해조칼슘에 의해 유의적으로 감소하였고 버섯분말 첨가량이 증가량이 증가할수록 낮아지는 경향을 보였다. 냉면의 색도는 버섯분말 첨가로 농도와 황색도가 낮아진 반면 해조칼슘은 이를 보완하는 경향을 나타냈으며, 생면에 비해 조리면에서 L값은 높아진 반면, a, b 값은 모두 감소하였다. 조리면의 농도는 기존 메밀냉면에 비해 버섯분말이나 해조칼슘을 첨가하였을 때 유의적으로 낮았으며, 황색도는 버섯분말 첨가로 감소하였다가 해조칼슘 첨가시 유의적으로 증가하였고, 적색도는 대조군과 3% 버섯분말 첨가냉면의 경우에는 적색보다는 오히려 녹색 쪽으로 기울었다. 버섯분말 및 해조칼슘 첨가에 따른 메밀냉면의 기호도를 비교한 결과, 풍미, 맛, 질감은 기존의 메밀냉면과 유의적 차이를 보이지 않았으나, 색깔과 수응도에서 5% 버섯분말 첨가 냉면이 가장 좋게 평가되었다. 결과적으로 냉면에 풍미는 버섯분말 첨가에 의해, 그리고 맛과 질감은 해조칼슘을 가함으로써 개선되는 것으로 해석할 수 있다.

• 한국잠사곤충학회지
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• 제43권1호
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• pp.21-25
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• 2001

Jeung-pyun added to mulberry leaves powder was tested to prove in inorganic ingredients, physical function, chromaticity and rheometer. For cake, mulberry leaves powder were added to rice flour in the ratio of 0%, 1%, 2%, and 3% respectively. In inorganic ingredients test, the amounts of calcium, magnesium and potassium were increased according to adding levels of mulberry leaves powder. But the amounts of iron, copper and zinc, were not correlated with it. Calcium, magnesium and potassium are anti-hypertension inorganic substances. Thus, it is considered that food with plenty amountsz of inorganic ingredients is an effective diet for the patients who suffer from cardiovascular disease. In physical evalution test, the ratio of mulberry leaves powder was not correlated with the appearance of Jeung-pyun. The value of color decreased as the ratio of mulberry leaves powder increases. In texture, Jeung-pyun. The value of color decreased as the ratio of mulberry leaves power increase. In texture, Jeung-pyun added with 2% mulberry leaves powder had the highest value. In moisture, as the level of mulberry leaves powder was increased, the value was decreased. In rheometer test, Jeung-pyun 0% mulberry leaves powder had the highest value in hardness. While the ratio of mulberry leaves powder was not correlated with cohesiveness. Jeung-pyun added to 1% mulberry leaves powder had the highest value. In gummines and brittleness, 0% Jeung-pyun had the highest value, but the ratio was not correlate with cohesiveness.

• 동력기계공학회지
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• 제18권3호
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• pp.93-99
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• 2014

The purpose of this paper is to manufacture the non-sintered ceramic used lime and industrial waste. The used materials were basalt powder sludge, calcium hydroxide(Ca(OH)2) and additives such as calcium stearate and $TiO_2$. The mixing ratios between Ca(OH)2 and sludge were 5:5, 6:4 and 8:2, respectively. The ceramic forms were pressured by 100, 200 and 300 bar and cured in 14% CO2 for 12 days. The behaviors of compressive strength, specific gravity, water absorption and pH of ceramic form were investigated. The results were compressive strength of over 36 MPa, water absorption of over 8.8%, pH value of over 12.3. And these results satisfied GR F 4006 and 4031 standard.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 봄 학술논문 발표대회
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• pp.213-214
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• 2021

External insulation method is used to conserve energy of buildings. However, the current external insulation method uses organic insulating materials to become a diffusion path in case of fire. In this study, the purpose of this study is to provide basic data on the required performance of the plastering material according to the CaCO₃ powder addition of the finishing material of the external insulation method. In Figure 1, when powder was added, the adhesion strength decreased by 30% to 35% at 10% and 0% to 50% at 20% compared to Plain. In Figure 2, the moisture permeability increases approximately twice when powder is added. The results for the water absorption coefficient are shown in Figure 3.

• 한국재료학회지
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• 제24권12호
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• pp.700-703
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• 2014

Calcium phosphate minerals are biologically important because of their application in the fields of orthopaedics and dentistry. Herein we have tried to synthesize calcium phosphate minerals from biowaste clam shells. A simple microwave method was used to synthesize a mixture of calcium phosphate minerals such as hydroxyapatite, tri-calcium phosphate, and monetite. The microwave induces vibration of the dipole ions in the reagent. The heating and rearrangement of ions and atoms occurs during the process. The phases obtained in the final powder were ascertained by X-ray diffraction; the morphology of each sample was checked using a scanning electron microscope. We were able to obtain a mixture of calcium phosphate minerals using the microwave method; the calcined powder showed a brick like morphology, which is different from the rod shape morphology of the hydroxyapatite obtained using the hydrothermal process.