• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.31-32
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• 2018

Lately, cement mixed siliceous powder waterproofing coating has been used as a waterproofing material in the wet environment condition of an underground concrete structure. Underground is exposed to environmental influences such as pressure of ground water, pressure of soil. However, the quality standard for pressure (water pressure, earth pressure) is not specified in the specification of the cement mixed siliceous powder waterproofing coating. Therefore, in this study, the permeability test was carried out based on the assumption that the durability should be verified in consideration of the environmental aspects of the material in actual field. As a result of the test, the permeability was generated from the inorganic single type material, but it was caused by the sealing failure and the test error, and the permeability was not generated in most of the materials. The results of this study will be analyzed by reviewing the physical properties of the material, and the research direction will be resumed.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.1
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• pp.10-14
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• 1994

The slowly released potassium fertilizer was developed by mixing fly ash with KOH, anthracite coal powder, KCI, $K_2CO_3$ and $Mg(OH)_2$ as the substances for accelerating calcination. Measuring proper ratios of raw materials, we found that the anthracite coal powder was 12 percent and $Mg(OH)_2$ was two to three percent. The optimal calcination temperature and time were proved to be $850^{\circ}C$ and 30 minutes, respectively, however, the trial product with lower temperature and shorter time in calcination had low quality. The K solubility of the product was very low compared to that of the KCl fertilizer.

• Korean Journal of Soil Science and Fertilizer
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• v.15 no.3
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• pp.188-193
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• 1982

Granulation formed from mixture of sulfate of potash (SOP) powder and pulverized silica minerals (Zeolite, Serpentine and Talc) was studied to establish granulation rate and physical properties of granules. These mixtures were granulated in a pan granulator with water and granules of SOP were coated with minerals powder. Mixture of SOP and mineral powder by half (w/w) were increased granulation rate compared with pure SOP powder, and talc was superior to them with SOP. Water was needed about 14% to granulate SOP powder alone, but it decreased by 2% with talc and increased by 4% and 2% with zeolite and serpentine, respectively. Granules of mixture of SOP with zeolite were harder than pure SOP granules but with another minerals powder decreased in hardness. Also breaking rate of granules in vinyl parcel falling from 2m height and abrasion rate of granules by agitation were improved by mixing and coating with zeolite but with the other were of inferior.

• Journal of the Korean Ceramic Society
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• v.53 no.3
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• pp.362-366
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• 2016

In this study, humidity control ceramics with good adsorption/desorption capabilities and high strength were fabricated from drinking-water treatment sludge (DWTS) and Onggi soil. The DWTS powder heat-treated at $800^{\circ}C$ and Onggi soil were mixed at weight ratios of 40:60, 50:50, 60:40, and 70:30 and fired at $800-1000^{\circ}C$. With increasing DWTS content, density and flexural strength increased. For the sample with a DWTS:Onggi soil weight ratio of 70:30, porosity and specific surface area decreased with increasing firing temperature, attributed to densification and grain growth at high firing temperatures. From the results obtained, a firing temperature of $800^{\circ}C$ is the optimum condition for fabricating humidity control ceramics with good adsorption/desorption capabilities and strength. The maximum adsorbed amount for the sample fired at $800^{\circ}C$ was $439g/m^2$.

• Journal of Korea Foresty Energy
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• v.20 no.1
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• pp.1-5
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• 2001

In this study, it was examined the effect of carbonized wastewoods on soil improvement and effect of charcoal size on tree seedling growth Thuja accidentalis seedlings grow better in the charcoal-treated soil than in the non-treated soil. Especially Pinus koraiensis charcoal with good adsorption. brought the best growth result. The charcoal treatment also improved the height growth of transplanted Aesuculus turbinate seedling However charcoal sizes(i.e. powder and particle) did not affect the growth of the seedling. Also apple trees which had been suffering from rotten roots caused by root rot was recovered by application particle-sized charcoal.

• Journal of Ginseng Research
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• v.33 no.2
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• pp.139-142
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• 2009

The effect of calcium cyanamide (China-made) soil fumigation on the growth of the ginseng pathogen Rhizoctonia, Pythium), soil microbes, and seed germination of lettuce and radish was investigated. At twice the recommended level (2S0-ppm $CaCN_2$), the growth of Rhizoctonia and Pythium, and the seed germination, were not inhibited. Rather, the effective level was 10,000 ppm. The powder form was more effective than the granular form in inhibiting pathogen growth and seed germination. The lettuce seed was also more sensitive than the radish seed. Calcium cyanamide appearedto decrease the fungi population and to increase Actinomycetes in the soil.

• Journal of Radiation Protection and Research
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• v.48 no.2
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• pp.77-83
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• 2023

Background: The purpose of this study is to purify uranium (U[VI])-contaminated soil-flushing effluent using the precipitation-distillation process for clearance. Precipitation and distillation are commonly used techniques for water treatment. We propose using a combination of these methods for the simple and effective removal of U(VI) ions from soil-flushing effluents. In addition, the U concentration (Bq/g) of solid waste generated in the proposed treatment process was analyzed to confirm whether it satisfies the clearance level. Materials and Methods: Uranium-contaminated soil was decontaminated by soil-flushing using 0.5 M sulfuric acid. The soil-flushing effluent was treated with sodium hydroxide powder to precipitate U(VI) ions, and the remaining U(VI) ions were removed by phosphate addition. The effluent from which U(VI) ions were removed was distilled for reuse as a soil-flushing eluent. Results and Discussion: The purification method using the precipitation-distillation process proposed in this study effectively removes U(VI) ions from U-contaminated soil-flushing effluent. In addition, most of the solid waste generated in the purification process satisfied the clearance level. Conclusion: The proposed purification process is considered to have potential as a soil-flushing effluent treatment method to reduce the amount of radioactive waste generated.

• Korean Journal of Medicinal Crop Science
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• v.12 no.6
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• pp.454-458
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• 2004

This study was carried out to clarify the effect of sulfur fertilization method on the qualities of safflower (Carthamus tinctorious L.) seed. Sulfur application increased the nitrogen and sulfur content of seed. In nitrogen content, there was no significant difference among sulfur fertilizers, whereas sulfur content was increased by raising ammonium sulfate (AS) amounts by soil application. In application method of AS, there was no significantly difference between foliar application and soil application with 8 kg S/10a. N/S ratio in seed was decreased by sulfur application, and also decreased with the increase of AS amounts by soil application. The contents of lipid and protein were increased by sulfur application. Lipid content was highest in foliar application, and protein content was lowest in AS 4 kg S/10a. By sulfur application, the content of total phenolics and electron donating ability (EDA) were increased by $3.1{\sim}4.7%$ and $3.6{\sim}8.5%$, respectively compared with control. In content of total phenolics, there was no significant difference among sulfur fertilizers, but EDA was higher in sulfur powder 20 kg/10a and AS 8 kg S/10a than that in other fertilizers. Sulfur application showed positive effects on the qualities of safflower seed. In application effects, AS and foliar application were more efficient than sulfur powder and soil application, respectively.

• Journal of Soil and Groundwater Environment
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• v.20 no.6
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• pp.127-132
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• 2015

In this study, biochar-bead, prepared from biochar powder derived from woody biomass, was used for removal cadmium ion in aqueous solution. Various mixing ratios of alginate solution and biochar powder were used for the production of round shape biochar-bead. An optimum mixing ratio was selected as 1.5% alginate solution and 20 wt% biochar. The produced biochar-bead was characterized by SEM, FT-IR, and XRD analyses. The adsorption capacity of Cd(II) by biochar-bead was found to be 9.72 mg/g which was higher than that by GAC and PAC. According to this study, round shape biochar-bead is expected to be used as a media for reactive barrier or water filtration.

• Korean Journal of Soil Science and Fertilizer
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• v.15 no.3
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• pp.166-171
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• 1982

A laboratiory experiment incubated at about $30^{\circ}C$ for 34 days was conducted in order to learn the effect of liming materials and rice straw on the volatilization of ammonia from flooded soils applied with urea. 1. The application of calcium hydroxide and calcium silicate increased buffer action of flood soil, though it resulted in increase in the volatilization of ammonia through raising flooded soil pH containing bicarbonate. 2. The mixing of rice straw powder to soil lowered pH of flooded soil, and decreased the volatilization of ammonia. The effect was particulary large when noliming material was used. 3. Calcium hydroxide depressed the evolution of $CO_2$ in the early days of incubation after flooding, while calcium silicate promoted the ammonification of soil nitrogen from the begining of flooding giving slow change in soil chemical properties. The rice straw was also effective in providing a favorable soil condition for the ammonification rather quickly.