• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.2
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• pp.44-50
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• 1997

Permeable polymer concrete can be applied to roads, sidewalks, river embankment, drain pipes, conduits, retaining walls, yards, parking lots, plazas, interlocking blocks, etc.. This study was to explore a possibility of using stone dust and heavy calcium carbonate as fillers for the permeable polymer concrete. Different mixing pro-portions were tried to find an optimum mixing proportion of the permeable polymer concrete. The tests were carried out at 20 f 1 t and 60 ${\pm}$ 2% relative humidity. At 7 days of curing, compressive, flexural and splitting tensile strengths and water permeability ranged between 209~246kgf/cm$^2$, 101 ~ l2lkgf/cm$^2$, 36~52kgf/cm$^2$ and 3.076 ~ 4.390L/cm$^3\;^2$/hr, respectively. It was concluded that the stone dust and heavy calcium carbonate could be used in the permeable polymer concrete.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.73-78
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• 2002

This study examines self-compacting of concrete using Ground Calcium Carbonate(GCC) gathering in limestone mine of Banyans district in order to make self-compacting concrete in the range of design strength 300kgf/cm$^2$ and the optimal mix proportion of self-compacting concrete that can use in field structure. The result shows that the optimal GCC replacement ratio is 45$\pm$5% in the normal strength of design strength 300kgf/cm$^2$ and that the volume ratio of the optimal fine aggregate used as the way satisfying both viscosity and compacting ability without separating materials is 46%. The optimal volume ratio of the coarse aggregate considering the economical aspect of concrete is 50%. It is desirable that the optimal mix proportion satisfying self-compacting for replacement of GCC is decided through mix design according to each replacement ratio.

• Journal of the Korean Graphic Arts Communication Society
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• v.21 no.2
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• pp.1-10
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• 2003

The Rheological properties are important factors in printing process. Specially, emulsification phenomenon is a very important factor that decides the quality of printing products in lithography. In this paper, I investigated the flow characteristics depending on calcium carbonate concentration for emulsified inks. By applying the data of this paper, I which to predict quality of printing product in practical printing process.

• Journal of environmental and Sanitary engineering
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• v.14 no.2
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• pp.84-89
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• 1999

This experiment was performed to develop the new desulfurization process which can eliminate the possibility of generation of the secondary pollutants by regenerating the limestone from the sulfite/sulfate slurry generated from the wet lime/limestone flue gas desulfurization process by treating it with the ammonium hydroxide and carbon dioxide and using it again. In the experiments, regent grade calcium carbonate was dissolved to obtain the 200ml of sample slurry of the concentration of 2.0~0.4 weight percent. After three times of regeneration and desulfurization process, the coefficients of regeneration and desulfurization efficiencies are calculated/measured. The obtained results are that the coefficients of generation of the first. second, and third regenerated calcium carbonate were 90.88, 92.13, and 91.50%, respectively; and the desulfurization efficiencies of those are 93.4, 94.2 and 93.0%, respectively.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.290-290
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• 2006

The toughening mechanisms of polypropylene (PP) containing 9.2 vol % of calcium carbonate ($CaCO_{3}$) nanoparticles were investigated using optical microscopy and transmission electron microscopy. Double-notch four-point bending (DN-4PB) Charpy impact specimens were utilized to study the fracture mechanism(s) responsible for the observed toughening effect. A detailed investigation reveals that the $CaCO_{3}$ nanoparticles act as stress concentrators to initiate massive crazes, followed by shear banding in PP matrix. These toughening mechanisms are responsible for the observed improved impact strength.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.217-220
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• 2006

This paper describes a study undertaken to determine the effect of ground calcium carbonate(GCC) cement mortar with respect to sulfate attack. It were investigated visual appearance and expansion of cement mortars with GCC immersed in artificial solution of 5% sodium sulfate during 510days. According to increasing replacement of GCC, the expansion ratio was comparatively superior to GCC0 mortar specimen. The test results indicated that cement mortars with GCC was benefit the resistance of sulfate attack due to micro filler effect.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.553-556
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• 2006

Generally, concrete is one of the most widely used construction materials, because of its good durability to cost ratio. However, when subjected to severe environments its durability can significantly decline due to various harmful conditions. In this article, we would like to investigate a chloride ion diffusion of cement matrix with inert filler, which ground calcium carbonate(GCC). For the experimental results of the chloride ion diffusion, as the addition of GCC makes decreasing the permeability by micro-filler effect, the matrix of 5-15% ratio of replacement are superior to the GCC0 mortar matrix with respect to durability of cement matrix in this scope.

• Proceedings of the Korea Concrete Institute Conference
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• 1993.10a
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• pp.65-70
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• 1993

The effect of particle size of Al powder, water repellent agent and finishing agent on frost resistance, absorption ratio and structure of micropore was examined to improve the physical properties and durability of ALC. According as the amount added of water repellent agent was increased, frost resistance was improved and absorption ratio was decreased. From one side freezing /thaw test, finishing agent which has a low vapor permeation located the crack at close indoor point of ALC specimen. ALC produced from fine Al powder has a low volume reduction by scalling and a sound appearance after freezing/thawing test and top surface freezing test, The crystal of tobermorite in ALC matrix was converted to calcium carbonate by carbonation which was accelerated with the decreasing of water content. Since the micropore of ALC was filled up by calcium carbonate, void ratio was reduced and crack was detected after complete carbonation.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2000.06a
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• pp.39-46
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• 2000

타조알의 형성은 배란된 난자가 나팔관과 난백분비부, 협부, 자궁 그리고 총배설강을 통과하면서 완전한 형태의 알로 산란된다. 그리고 1 clutch size가 40$\pm$15개 정도이다. 알의 크기는 1,450g에서 200~400g의 변이가 있는 것으로 본다. 타조의 난질에는 cuticle 층이 없어서 병원균의 침입에 약하다. 그리고 알의 껍질은 2mm 정도로 두꺼우며 그주요 성분은 달걀의 껍질에서와 마찬가지로 calcium carbonate이다 타조알의수거는 수놈의 방해가 없도록 하여야 하며 bacteria나 fungi의 침입이 업도록 하여야 한다. 수거된 알은 저장하였다가 부화기의 수용능력이 되면 부화를 시작한다. 부화 전에 아를 저장할 경우 15~18$^{\circ}C$로 저장실 온도를 유지하면 7일 정도 저장이 가능하지만 7일 이상 저장할 경우 12$^{\circ}C$로 저장온도를 낮추고 이때 상대습도는 75%로 유지하는 것이 이상적이다. 부화기의 온도는 36.0~36.5$^{\circ}C$가 이상적이며 이때 이상적인 습도는 35%이하이어야 한다. 또 부화중 전란을 하여야 하는데 대개 한시간에 한번씩 74~90。로 전란 해주는 것이 바람직하다. 부화에 적당한 알은 기형적으로 크거나 작으면 부화율을 높이지 못한다.

• Journal of Forest and Environmental Science
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• v.18 no.1
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• pp.97-105
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• 2001

The main objective of this study was to investigate effects of pigment mixed with different ratio on the double coated paper. Mineral pigments such as clay and ground calcium carbonate(GCC) as well as hollow sphere plastic pigment were used to evaluate the physical, optical properties and printabilities of double coated paper. The physical properties such as gloss and smoothness, and the printability(ink gloss) of double coated paper were measured to evaluate the effects of the bottom layer on improving the properties of top layer. The data indicated that the usage of hollow sphere plastic pigment for the bottom layer coating improved the surface properties of double coated paper, and that ink gloss was significantly influenced by the structure of bottom layer even when hollow sphere plastic pigment was used for the bottom layer coating.