• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 추계 학술논문 발표대회
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• pp.160-161
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• 2013

Recently, the enviroment problem is serious due to the global warming phenomenon because of the greenhouse gas exhaustion. In addition, the effort to reduce the problem in the situation where the severity of the destruction of environment because of the indiscriminate picking of the that is the raw material of the cement, Accordingly, in the interior of a country, the industrial site using the artificial stone instead of the natural stone is increased. Thus the cement reduction amount of use and substitute material research is the urgent actual condition with the gas emission, which here it is generated in conducting compression molding in the building stone manufacturing process performance degradation phenomenon and fire resistance, and problem of the durability. limestone and aggregate and exhaustion of resource are emphasized is continued. In this research, the fly ash and waste porcelain is applied to the magnesia phosphate composite (MPC) and the characteristic of the artificial stone according to it tries to be looked into.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 추계 학술논문 발표대회
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• pp.143-144
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• 2019

Recently, environmental pollution related to global warming is on the rise. Meanwhile, renewable energy is a representative example of many efforts to develop eco-friendly energy to solve the depletion of natural resources and the depletion of petroleum resources in conjunction with global warming. Among them, photovoltaic power generation is increasing the subsidies for the government to increase the production of photovoltaic electricity of the general public, showing a high growth rate. However, polysilicon, which is a raw material of the photovoltaic panel, generates waste called polysilicon sludge in the manufacturing process. In order to produce 1 ton of polysilicon, about 2 tons of waste polysilicon sludge is generated. In 2012, polysilicon sludge was generated at 78,000 tons, with an average of about 220 tons per day. The sludge generated due to insufficient treatment of polysilicon sludge is currently solidified and is processed by landfilling. Therefore, in this study, polysilicone sludge is used as the concept of admixture, and the physical properties of the matrix according to the polysilicon sludge replacement ratio based on light burned magnesia is determined.

• 한국산학기술학회논문지
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• 제18권7호
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• pp.357-364
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• 2017

본 논문에서는 생물학적 판넬의 모재로써 마그네시아-인산칼륨 복합체의 품질을 제어하기 위하여 마그네시아-인산칼륨 복합체의 혼합비와 물-결합재비(W/B)에 대한 유동 및 압축강도의 영향을 고찰하고자 하였다. MPPC는 W/B 7수준(30, 35, 40, 45, 50, 55 and 60 vol. %) 및 인산칼륨 및 마그네시아 비율(P:M) 4수준(1;0.5, 1;1.0, 1;2.0 and 1;3.0)으로 제조하였으며, 실험결과, MPPC의 유동 및 압축강도는 P:M비 및W/B에 크게 의존하는 것을 확인할 수 있었다. MPPC의 플로우는 P:M이 증가할수록 반응을 위한 배합수의 부족으로 혼합이 되지 않는 것으로 나타났으며, 이러한 원인은 P의 밀도와 M의 밀도가 크기 때문인 것으로 나타났다. 또한 MPPC의 압축강도는 P:M이 증가함에 따라 강도가 감소하는 경향이 나타났으나 W/B에 따라서는 비례적인 변화가 나타나지 않아 모순된 결과가 나타났다. 이러한 결과는 MPPC의 경우 W/B에 따라 최적의 배합비율이 존재함을 확인할 수 있었다. 본 논문의 이러한 결과를 통하여 생물학적 판넬 설계시 재료적 측면에서 모재 재료의 유동성 및 압축강도에 대한품질 제어를 위한 기반자료로써 활용하고자 한다.

• 시멘트 심포지엄
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• 통권37호
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• pp.244-250
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• 2010

• 대한화학회지
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• 제9권1호
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• pp.49-54
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• 1965

One of the difficult and time consuming problems in the production of magnesia from sea water is a settling rate of magnesium hydroxide. In this experiments, authors attempted to accelerate its settling rate by addition of various sedimenting agents as C.M.C., Separan and Starch, and sought for optimum calcination temperature for domestic dolomite, as alkali source, mole ratio of dolomite milk to bittern. It is observed through experiments that the small amounts of sedimenting agents, C.M.C., Separan, starch, 20 mg/l, 40 mg/l, 400mg/l, respectively increase the settling rate of magnesium hydroxide by 8 times or more. The following conditions resulted in good yield of magnesium hydroxide from sea water with relatively tolerable calcium oxide contaminated for the magnesium clinker. Calcinating temperature, $1,100{\sim}1,200^{\circ}C$, mole ratio of 10% dolomite milk to magnesium salts in sea water or bittern, 1. 2 : 1.

• The Korean Journal of Ceramics
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• 제5권4호
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• pp.395-399
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• 1999

MgO/metal nanocomposite powder mixtures were prepared by solution chemical processes to obtain suitable structure for ceramic/metal nanocomposites. Nickel or cobalt nitrate, as a source of metal dispersion, was dissolved into alcohol and mixed with magnesia powder. After calcined in air, these powders were reduced by hydrogen. Densified nanocomposites were successively obtained by Pulse Electric Current Sintering (PECS) process. The dispersed metal partical size depended on temperature and time in calcination and reduction processes. The phase analyses in the synthesized powders as a functioni of temperature were tracked using a dynamic high temperature X-ray diffractioni (HTXRD) system. Phase and crystallite size analyses were done using X-ray diffractioni and TEM. The MgO/metal nanocomposites were successfully fabricated, and ferromagnetic responses with enhanced coercive force were also investigated for these composites.

• 한국세라믹학회지
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• 제31권9호
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• pp.1053-1059
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• 1994

The influence of ZrO2 addition on microstructre and mechanical strength of magnesia ceramics were discussed. ZrO2 was existed as a cubic phase resulted from MgO solubility into ZrO2 on firing at temperature range from 130$0^{\circ}C$ to 1$600^{\circ}C$ for 2 h. The addition of ZrO2 markedly promoted the densification of MgO also above 150$0^{\circ}C$ and the sintered density at 1$600^{\circ}C$, 2 h reached to 95.2% of the theoretical. The solubility of MgO into c-ZrO2 was about 7.68 wt% and it was segregated at grain boundary on cooling to room temperature. ZrO2 existing as a second phase retarded the grain growth of MgO. The bending strength were increased to 240 MPa with the amount of ZrO2.

• 한국세라믹학회지
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• 제33권2호
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• pp.235-241
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• 1996

Self-Propagating high temperature synthesis(SHS) technique was used to synthesize the spinel phase of MgAl2O from MgO and Al powder. Processing factors such as mixing time preheating temperature and ignition catalyst were varied to determine the optimum condition to form MgAl2O4 phase. The reaction products were heat treated at the temperature range of 120$0^{\circ}C$ and 150$0^{\circ}C$. to observe phase transformation of unreacted materials. Processing factors such as 48 hrs-mixing 80$0^{\circ}C$-preheating and 20wt% KNO3-ignition catalyst were effective of the formation of MgAl2O spinel. An activation energy 49.7kcal/mol. was calculated to form a MaAl2O4 spinel from unreacted materials.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.51-52
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• 2014

Recently, it is the global warming phenomenon because of the greenhouse gas exhaustion caused by and the environment problem is serious. And it is the situation where the problem of the exhaustion of resource because of the indiscriminate picking of the that is the raw material of the cement, limestone and natural aggregate are emphasized. In addition, thus the cement reduction amount of use and substitute material research is the urgent actual condition with the gas emission, which here it is generated in conducting compression molding in the building stone manufacturing process performance degradation phenomenon and fire resistance, and problem of the durability. Therefore, in this research, because of being the magnesia phosphate ceramics, the waste porcelain is applied and the anti-wearing character of the artificial stone according to it tries to be investigated.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2000년도 추계학술발표대회 논문집
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• pp.212-215
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• 2000

For the production of high strength constructional glass reinforced plastics and various composite materials continuous glass fibers of high strength and increased modulus of elasticity are used. As is known, the glasses with highest strength were obtained in magnesia alumosilicate and magnesia lime-alumosilicate systems when introducing oxides of titanium and zirconium, boric anhydride, etc. in some cases. The experimental investigations have shown that some glass compositions are characterized by the ratio viscosity/crystallization which is favourable for glass fiber drawing process that permits the attainment of high strength level at the conditions of high temperature glass melting and formation.