• Proceedings of the Korea Concrete Institute Conference
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• 1998.10c
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• pp.151-156
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• 1998

Concrete structures is appeared the shrinkage after being harden of the hydration effect of cement. To overcome this disadvantage, expansive additives are used. In our country, the most popular expansive additives are hauyne(CSA) or free lime(free-CaO) systems. These expansive additives are used to expansive cement mortar or concrete materials. In this study, we analyzed the expansive property mechanism about the hydration reaction of the free lime systems and in particular we convinced size distributions of the free lime size affect the expansion ratio with expansion ratio with experiments. We carried out the experiment for the expansive properties by using the soundness molds and with various the humidity and dry setting conditions. The hydration reactions of the free lime affect the reaction properties according to the relative humidity by laboratory experiments.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.373-376
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• 2008

New glass compositions for lead free, low temperature sealing glass frit was examined in $ZnO-V_2O_5-P_2O_5$ glass system which can be used sealing material for PDP to be made of soda lime glass substrates. Among many glass compositions, KFS-C glass showed low glass transition point (Tg) and good fluidity and adhesion characteristics when it was tested by flow button method at low temperature of $420^{\circ}C$. Its Tg was $317^{\circ}C$ and thermal expansion coefficient (CTE) was $70{\times}10^{-7}/K$. The glass frit was mixed with an organic vehicle to make a paste and it was dispensed and sealed with soda lime glass substrates at $420^{\circ}C$ for 10min. Sealed glass panels also showed good adhesion strength even sealed at low temperature of $420^{\circ}C$.

• Cement Symposium
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• no.21
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• pp.98-101
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• 1993

• Cement Symposium
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• no.29
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• pp.245-252
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• 2002

소성 영역(Sintering zone)에서 클링커(Clinker)의 형상 형성은 시멘트 생산 공정에서 가장 중요한 생산 공정중의 하나이다. 소성공정의 진단 및 최적 제어의 핵심은 써모그래프(Thermo graph), 즉 적외선 카메라를 이용한 온도 분포의 측정이다. 여기에서 다룰 ''PIT Indicator'' 시스템은 분진이 많은 열악한 산업 현장의 연소 시스템에 적용할 수 있도록 특별히 설계한 공냉식의 2개 채널을 가진 광학 장비에 기초하고 있다. 비디오 영상과 써모그래프 이미지 그리고 다양한 연소 특성이 카메라를 통하여 얻어지고 자기 학습 기능을 가진 소프트웨어에서 기록되고 분석된다. 이때 얻은 데이터는 수학적 모델에서 온라인으로 Free Lime 함유율을 예측하는데 이용된다. 열분포의 써모그래프 표시와 공정상의 다양한 운전 특성을 분석하여 주는 ''PIT Indicator'' 소프트웨어를 통하여 다른 공정 제어 시스템과 연결이 가능하다. 이와 같은 하드웨어와 소프트웨어를 이용하여 최적화가 필요한 여러요소들의 최적화를 동시에 그리고 온라인으로 수행할 수가 있다. Free Lime 함유율의 연속적인 온라인 연산을 통해 생산 설비 및 공정에 맞는 최소한의 에너지를 Kiln 에 공급함으로써 근본적으로 1차 연료의 절감이 가능하고 NOx와 같은 유해 가스의 배출량도 제어할 수 있다. 또한 별도로 NOx에 대한 모델을 개발하여 NOx를 정확하게 예측하는 것도 가능하다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.8
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• pp.755-759
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• 2008

For the development of a new white dielectric layer in plasma display panel, different $TiO_2$ types as a filler was add to the $Bi_2O_3$-BaO-ZnO glass matrix. The reflectance and dielectric constant of dielectric have been investigated as a function of the mixing content (rutile and anatase), and sintering temperature. The reflectance of dielectric sintered at the 520$^{\circ}C$ appeared most highly and suitable in terms of the adhesion and reflectance of the soda-lime glasses. Also, the thermal expansion coefficient of dielectric was found to be $85.6\times10^{-7}/K$, which was similar to that of the soda-lime glasses. Especially, the dielectric constants were not increased with increasing of $TiO_2$ filler contents.

• Journal of the Korean Ceramic Society
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• v.19 no.1
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• pp.19-23
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• 1982

The technique to determine the components in the supersulphated slag cement is discussed by several selective extraction analyses. Accordingly, the rate of hydration reaction of supersulphated slag cement could be quantitatively measured by the following 3 kinds of the selective extraction analyses. (1) Determination of unreacted slag - a salicylic acid, acetone.methanol solution (2) Determination of free $CaSO_4$ - a half saturated lime water (3) Determination of free $Ca(OH)_2$ - glycerine.alcohol solution

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.3
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• pp.210-218
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• 1991

This study was carried out to investigate the influence of inoculation with Bradyrhizobia and lime types on the nutrient content and yield of peanut. Inoculation size of Bradyrhizobium sp. HCR-46 was $8.2{\times}10^7$ cells per seed. Slaked lime, magnesium lime, and calcium carbonate were applied in an amount required for neutralization of soil. 150kg of calcium sulfate was fertilized to 10a of the experimental field. Sowing space was $40{\times}25cm$ under vinyl mulching. Leaves and stems for assay were sampled at 100 day after sowing. The obrained results are as follows. 1. Number and dry weight of nodule as well as dry weight of aerial part of peanut plant increased by inoculation with B. sp. and were the highest in calcium carbonate application. 2. Inoculated with B. sp., the contents of T-N, $K_2O$, MgO, allantoin, ammonia, free amino acid and chlorophyll increased, but that of nitrate decreased. 3. The contents of T-N, free amino acid, and chlorophyll were higher in the treatment of calcium carbonate, those of $K_2O$, MgO, allantoin, ammonia were higher in magnesium lime application, and those of CaO and nitrate were higher in slaked lime fertilization than any other lime types. 4. Contents of total sugar and starch in stem at 100 days were higher in the treatment of uninoculation than inoculation with B. sp., and those were highest in the calcium sulfate application than the other lime types. 5. Inoculated with B. sp. length of main stem and number of pods increased significantiy. Yield of seed was higher in inoculation with B. sp. than in uninoculation by 64%, and in the order of carbonate, magnesium lime, slaked lime, in calcium sulfate and non-application was the contribution of soil treatments to yield increases.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.367-370
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• 2007

An EEFL with the sodium free alumino-silicate glass of high K and low $tan{\delta}$, has been investigated. As compared with borosilicate and the soda-lime EEFLs, the luminous efficiency as well as the pinhole stability of new EEFLs improves remarkably without blackening of $NaHg_2$.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.514-519
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• 2001

Converter has been slag produced 10 million tons per year in Japan. It is a steel making by product produced in the same way as the blast-furnace slag. Though blast-furnace slag is being used effectively as a concrete admixture, the converter stag has never been used effectively because of the expansion action of contained free lime and iron oxide. This is an important environmental problem in the steel industry. Beta-2CaOSiO$_2$(beta-C$_2$S) is contained 40 percent in converter slag, therefore it is very promising as a concrete admixture. We proposed an accelerated aging processes capable of stabilizing the converter slag in a short time. The converter slag is dipped into alkali aqueous solution after heating at low temperature. It was subsequently ground to a grain size of 75 ${\mu}{\textrm}{m}$ , inner 30 percent of OPC. The properties of mortar and concrete using the blended cement were determined. As a result, it has become apparent that the expansion was reduced and long term compressive strength was increased while that at early ages was not so remarkable. The hydration exotherm rate was lower than that of the OPC.

• Journal of the Korea Institute of Building Construction
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• v.11 no.5
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• pp.442-451
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• 2011

Blast furnace slag is recycled as a high value-added material, while steel slag is difficult to recycle or is recycled as a low-grade filler material due to its expansive characteristics. Its property is caused by the high content of free lime and instable steel oxides. Recently, an innovative and rapid cooling method for melting steel slag has been developed in Korea, which reduces free lime content to a minimum level and increases the stability of steel oxides. However, researches on the long-term stability are not sufficient so far. Therefore, this study, focusing on the electric arc furnace oxidizing slag in the steel slag, aims to investigate the properties of the steel slag aggregate, its long-term volume stability and the engineering strength of mortar, and using it as a fine aggregate. This study result indicated that it was possible for it to be used as concrete aggregate because the volume change of the steel slag appeared to be stable.