• Korean Journal of Agricultural Science
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• v.31 no.2
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• pp.105-114
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• 2004

This study was performed to examine the physical and mechanical properties of eco-concrete using soil, natural coarse aggregate, soil compound and polypropylen fiber. The mass loss ratio was decreased with increasing the content of coarse aggregate and soil compound. The compressive strength, flexural strength, ultrasonic pulse velocity and dynamic modulus of elasticity were increased with increasing the content of coarse aggregate, soil compound and polypropylene fiber. The compressive and flexural strengths were showed in 8.07 MPa and 2.641 MPa at the curing age 28 days, respectively. The coefficient of permeability was decreased with increasing the content of coarse aggregate and soil compound, but it was increased with increasing the content of polypropylene fiber. The lowest coefficent of permeability was showed in $5.066{\times}10^{-9}cm/s$.

• Culinary science and hospitality research
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• v.20 no.1
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• pp.178-188
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• 2014

Two kinds of anticaking agents (dextrin, polydextrose) were combined with kiwifruit paste at 5% w/w ratio and freeze-dried to prepare a powdered material. The physiochemical characteristics of kiwifruit powders with anticaking agents were compared with those without anticaking agents as the control. The yield was higher in the powders with anticaking agents than the control. Moisture content, acidity, and total phenolics were lower in the powders with anticaking agents than the control. The contents of vitamin C was higher in the powders with anticaking agents than the control, but was no significant difference with different anticaking agent types. There were no significant differences in free sugar content (fructose, glucose, total sugar) and organic acid content (oxalic acid, lactic acid, total) depending on the anticaking agent types. Hunter's L-value was significantly high in the order of the samples with dextrin, the control, and polydextrose, while a-value showed an opposite tendency. Browning index, water solubility, and swelling power didn't show any significant difference. However, the hygroscopicities with elapsed time were lower in the powders with anticaking agents than the control. Therefore, the kiwifruit powder combined with dextrin or polydextrose as an anticaking agent at 5% w/w ratio could be used as a food biomaterial with a good quality in moisture, vitamim C, color value, browning index, water solubility, and hygroscopicity.

• Journal of Convergence for Information Technology
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• v.7 no.1
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• pp.67-73
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• 2017

Paper sludge ash, blast furnace slag, fine powder quicklime, anhydrous gypsum, and fly ash as the main ingredients were prepared to suit the salty soils of marine soils. The solidification component is a kind of recycled ceramic, and CaO plays an important role in solidification. The neutralization time after solidification was about 2 weeks, and the compressive strength was about 12N/mm2 in the mortar test after one week incubation with standard yarn. This is about 14 times stronger than the solidifying agent used in the metropolitan area. As a result of applying plate load test to saltous marine soils, we obtained the yield load that can pass the large scale even after 5 days. In the uniaxial compressive strength test, shear strength of about 300 kPa was obtained after 5 days. It will be useful for supplementing the soft ground in the area where marine reclamation is much like the Incheon area.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.219-221
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• 2004

국가의 규제기관과 처분장에서는 방사성 폐기물의 안전한 영구처분을 위하여 폐기물 수용(인수)기준을 폐기물 발생자에게 준수토록 요구하게 되는데 이러한 폐기물 수용(인수)기준은 처분시설의 가동동안 인간과 환경 보호 그리고 최대 300년간의 제도적 통제기간을 고려하여 처분장의 안전성 확보를 위하여 설정되어진다. 폐기물 수용(인수)기준중 고화체의 안정성 평가와 관련하여 미국(NRC/BTP)은 폐기물의 종류와 고화매질에 따라 유리수, 압축강도, 방사성 조사특성, 미생물 영향 특성, 침수 및 침출 특성, 열순환 특성 등에 대하여 표준시험법을 제시하였으며, 또한 그의 기술기준치도 제시하고 있다. 그리고 프랑스(DRDD/ BECC)에서는 미국보다 매우 세밀하게 평가항목들을 분류하는 등의 처분장 운영국가에서는 고화체의 안정성관련 평가시험들을 처분 환경과 처분방식에 맞게 표준화하고 있다. 한편 국내에서는 과기부 고시 제2001-32호 "중.저준위 방사성폐기물 인도규정"이 있으나 이에는 고화체 관련하여 정성적인 안정성에 대하여서만 기술되어 있다. 이에 따라 원전폐기물 고화체에 대한 안정성 평가를 위한 시험법을 선정하기 위하여 아래 그림과 같은 절차에 따라 수행토록 하였다. 우선 대표적인 천층처분 운영국가인 미국과 프랑스의 시험법 그리고 IAEA 권고 시험법과 유사관련 한국 산업표준법들을 조사하고, 이들 시험법들의 주요 차이점을 기술적 관점에서 비교평가하고, 이어서 모의 방사성 및 비방사성 고화체를 이용하여 상기 시험법들을 각각 적용하고 또한 이들 시험법들간의 차이(시험 조건, 시편의 크기 등)에 기인한 상호 비교시험을 통하여 얻어진 시험결과들을 종합적으로 비교 검토하여 보수적 관점에서 시험법을 선정하는 것으로 방향을 잡았다. 이때 시험결과를 얻기 위한 모든 과정에 품질보증 활동을 적용키로 하였으며, 시험결과 분석/평가 과정과 시험법 선정에 각계(규제기관, 학계, 발전소 현장 및 산업계 등) 전문가로부터 기술자문회의를 통하여 자문 의견을 받기로 하였다. 특히 현재 폐기물 인수 기술기준치가 설정된 국가의 시험법을 심층 있게 검토하기로 하였다.검토하기로 하였다.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.4
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• pp.297-308
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• 2007

The granulation equipment of concentrated wastes is manufactured for the polymer solidification of concentrated wastes. It uses liquid sodium silicate as a granulating agent for the granulating of dried powder containing boric acid. The granulating agent is sprayed in the form of droplet and mean size of dried granules is $2{\sim}4mm$. The new technology which has been used for the polymer solidification of spent resin in U.S. and certified by Nuclear Regulatory Commission (NRC) is successfully applied to concentrated wastes. This uses in-situ solidification process within drum without mechanical mixing. Maximum loading of waste can be achieved without increasing of waste volume. Polymer waste forms were evaluated with several test such as fire test, compressive strength test, leaching test, immersion test, irradiation test, and thermal cycling test according to standard test procedures.

• Journal of the Korean Geosynthetics Society
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• v.11 no.3
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• pp.37-42
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• 2012

The cement paste is mostly used as the filling materials of bored pile in Korea. The use of filling material based on cement paste is inefficient at field construction because it needs a lot of the charging mass. In addition, it has environmental problem according to the large amount of cement use because its strength is also larger than criterion. The excavated soil with stabilizer can be used as the filling materials when the bored pile is constructed. Therefore, this paper describes field application of solidified soil for economical efficiency and environment-friendly. The injection capacity of solidified soil is compared with cement paste's based on unconfined compressive strength test and field load test, and the appropriate of test results is evaluated by design criterion. The evaluation result shows that the capacity of excavated soil with stabilizer is similar to cement paste and the solidified soil is able to apply as filling materials of bored pile because it is satisfied with design criterion.

• Applied Chemistry for Engineering
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• v.17 no.4
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• pp.391-396
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• 2006

When radioactive wastewater was solidified treatment by cement, the drying rate of cement and the volume reduction ratio was decreased because of boric acid component in the wastewater. In order to supplement the demerit, effects of paraffin wax investigated in this study. Paraffin wax has a hydrophobic properties and a low affinity with inorganic materials. When the radioactive wastewater was tested by a small of wax, the compressive strength of solidified waste are decreased Therefore boric acid in radioactive wastewater are first treated by alkali salt and coated by the stearic acid. During the solidification step, The amount of paraffin wax addition get the result that the compressive strength of solidification with cement was the same as that with paraffin wax. The leaching properties of radioactive waste solidified was the same CFL (cumulative fraction leached), PR (penetration rate), effective diffusivity if paraffin wax content in solidified waste was 20% or 25%.

• Journal of the Mineralogical Society of Korea
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• v.18 no.4 s.46
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• pp.301-312
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• 2005

The present study investigated the physical changes and reaction products with setting time after mixing of various mineral admixtures such as lime, hydrated lime, gypsum, kaolin, zeolite and diatomaceous earth with four types of cement (portland cement, slag cement, quick lime, hydrated lime) and clay rich sediments in soft foundation. As results, slag cement showed the greater compressive strength than normal portland cement. The mixing experiments with various mineral admixtures and slag cement resulted that gypsum showed the greatest compressive strength. Additionally, we conducted mixing experiments with various mixing ratios of gypsum and slag cement. The experiments showed that the mixing ratio of $30\%$ gypum and $70\%$ slag cement has the greatest compressive strength. Ettringite was produced as a reaction Product. This fact indicates that gypsum effectively promotes hydration reaction and contributed to the greater compressive strength. These experimental results can be used as fundamental data for the stabilization of soft clay foundation.

• Journal of the Korean Geotechnical Society
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• v.27 no.9
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• pp.47-53
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• 2011

Marine dredged soils taken from navigation channels or construction sites of coastal area usually have a lot of salt in pores of clayey soils. This paper investigates effect of salt on mechanical characteristics of non-salt and salt-rich stabilized dredged soil. The stabilized dredged soil (SDS) consisted of dredged soil and cement. Several pairs of SDS with non-salt and salt-rich dredged soils, noted as N-SDS and S-SDS, respectively, were prepared to compare their strengths and compressibility characteristics. The microstructures, strength and compressibility characteristics of N-SDS and S-SDS specimens at 7 and 28 days of curing time were evaluated using scanning electronic microscope (SEM), unconfined compression test, and oedometer test. It was found that salt concentration of clayey soil affected not only the formation of soil structure but also the strength development of mixture. The compression index and swelling index of S-SDS were also greater than those of N-SDS, which indicated that the compressibility of mixture increased due to salt concentration. Salinity in clayey soil had a negative effect on the strength development and compressibility characteristics of stabilized dredged soils.

• Journal of Radiation Protection and Research
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• v.10 no.2
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• pp.113-121
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• 1985

For the safety assessment of radwaste treatment and disposal, the leaching characteristics of $Cs^+\;and\;Sr^{++}$ from the cement-solidified radwastes was investigated by means of the survey and analysis of the activity leach rate and cumulative leach fraction of $^{137}Cs\;and\;^{90}Sr$ leaching from solidified radwastes. The cylindrical cement-solidified samples were made by the sodium silicate method and neutralization method changing the mole density of simulated liquid radwaste, type of cement, adding material and concentration of boric acid. The leaching study was carried out by the method using simulated PWR concentrated liquid radwaste solidified in cement that had been processed following the recommendations of IAEA. All the experimental results are in well accordance with the research data reported previously, but the watertight cement-solidified radwastes show rather high leach rate of radioactivity. It is learned, therefore, that the watertight cement is not adequate as the material for the solidified radwastes.