• Congress of the korean instutite of fire investigation
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• 2011.04a
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• pp.102-116
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• 2011

With the spread of FMD and AI in the country livestock farmers have used lime(CaO) prevalently and due to incorrect storage lime served as a fire ignition source in a number of cases. As combined chemically with water, lime has exothermic reaction. Then In these experiments we want to know how exothermic reaction - caused by lime - acts as sources of fire ignition in any circumstances and conditions. So we have done experimental work of ignition temperature and ignition process in the artificial conditions as lime combined chemically with water. As a result, we have confirmed that lime could be flammable material sufficiently as a fire ignition source with the proper presence of heat and moisture conditions. If the lime served as sources of fire ignition, as identification techniques of fire scene, we must ascertain the existence of water, flammable material and Calcium Hydroxide($Ca(OH)_2$). We should take special precautions in order to prevent fire and educate the safe handling of lime to the manufacturer and agricultural cooperative's joint livestock farmers who product or use lime.

• Proceedings of the Korean Environmental Health Society Conference
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• 2004.12a
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• pp.51-62
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• 2004

Lime based stabilization/solidification (S/S) can be an effective remediation alternative for the immobilization of arsenic (As) in contaminated soils and sludges. However, the exact immobilization mechanism has not been well established, Based on previous research, As immobilization could be attributed to sorption and/or inclusion in pozzolanic reaction products and/or the formation of calcium-arsenic (Ca-As) precipitates. In this study, suspensions of lime-As were studied in an attempt to elucidate the controlling mechanism of As immobilization in lime treated soils. Aqueous lime-As suspensions (slurries) with varying Ca/As molar ratios (1:1, 1.5:1, 2:1, 2.5:1 and 4:1) were prepared and soluble As concentrations were determined. X-ray diffraction (XRD) analyses were used to establish the resulting mineralogy of crystalline precipitate formation. Depending on the redox state of the As source, different As precipitates were identified. When As (III) was used, the main precipitate formation was Ca-As-O. With As(V) as the source, Ca4(OH)2(AsO4)2${\cdot}$4H2O formed at Ca/As molar ratios greater than 1:1. A significant increase in As (III) immobilization was observed at Ca/As molar ratios greater than 1:1. Similarly, a substantial increase in As (V) immobilization was noted at Ca/As molar ratios greater than or equal to 2.5: 1. This observation was also confirmed by XRD. The effectiveness of both As (III) and As(V) immobilization in these slurries appeared to increase with increasing Ca/As molar ratios.

• Applied Biological Chemistry
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• v.7
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• pp.45-52
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• 1966

This study was carried out to determine how the water soluble, the available $P_2O_5$ and urea-N would change in the course of time, when the mixtures of calcium superphosphate and urea with lime for fertilizer which occurred in Korea and largely contained calcium carbonate were made. Three kinds of materials, i. e., calcium superphosphate, urea and lime for fertilizer were used in this study. Three kinds of mixed fertilizer, i. e., A, B and C were made up by mixing these materials to satisfy the following formula. $$1)\;Ca(H_2PO_4)_2+CaCO_3+CO(NH_2)_2{\rightarrow}$$$$Ca_2H_2(PO_4)+H_2CO_3+NH_3$$ $$2)\;Ca(H_2PO_4)_2+CaCO_3+CO(NH_2)_2{\rightarrow}$$$$Ca_3(PO_4)_2+H_2CO_3+NH_3$$ $$3)\;Ca(H_2PO_4)_2+CaCO_3+CO(NH_2)_2{\rightarrow}$$$$Ca_3(PO_4)_2+H_2CO_3+CaCO_3+NH_3$$ A,B and C were placed in desiccators respectively a six month period. During the time of storage, the water soluble, the available phosphoric acid and urea-N were measured once a month, seven times with the control measurement. The results may be summarized as follows. 1. None of A, B and C showed any change in the urea-N with the lapse of time. This fact indicated that the combination of calcium superphosphate and urea with lime for fertilizer was not unfavourable. 2. A, B and C decreased in the amount of water soluble $P_2O_5$ with the passage of time. This fact indicated that the mixing of calcium superphosphate and urea with lime for fertilizer was unfeasible. 3. The available $P_2O_5$ in any of A,B and C did not undergo a change as time went by. This fact suggested that the combination of calcium superphate and urea with lime for fertilizer was favourable.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.1
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• pp.12-15
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• 2022

The effect of SiO₂, Na₂O and CaO on isokom temperatures in soda-lime glass is estimated by comparing calculated isokom temperatures using viscosity model proposed by Lakatos. The isokom temperatures at the viscosity of log η = 12.3, 10, 6.6 and 1 (Pa·s) are lowered by 6, 7, 10 and 24℃, respectively, by the substitution of SiO₂ with Na₂O by 1 mol%. Meanwhile, replacing 1 mol% of SiO₂ with CaO raises the isokom temperatures by 3~4 and 2℃ at the viscosity of log η = 12.3 and 10 (Pa·s), respectively, but lowers the temperatures by 1 and 21℃ at the viscosity of log η = 6.6 and 1(Pa·s), respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.1
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• pp.39-44
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• 1989

This experiment was conducted to mature newly reclaimed upland and to increase soybean yield at this upland, Kim Jae, Jeon Buk, Koera from 1987 to 1988. Lime, lime-magnesium and calcium sulfate were applied with two, levels, amount of lime requirement, and 1.5 times of lime requirement. The results were summarized as follows: 1. The yields of soybean among treaments were in order of lime-magnesium 1.5 times, lime 1.5 times, lime-magnesium, calcium sulfate, lime and control with significancy at 1% level. 2. Correlations between yield components and inorganic element contents (T-N, $P_2O_5$, CaO and MgO) in plant at flowering stage were positive, but manganese in plant was negative at 5%, respectively. 3. Correlations, between yields and MgO and CaO contents in plant at flowering stage were positive, but Mn in plant was negative at 5% respectively. 4. Inorganic element contents of the soils at flowering stage were higher than those of before experiment. Correlation between yield and base saturation degree in soil at flowering stage was positive at 5%.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.215-216
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• 1999

연소시설, 소각시설 등에서 배출되는 아황산가스, 질소산화물, 염화수소, 불화수소 등의 산성가스를 경제적, 효율적으로 처리하는데 많은 관심의 대상이 되고 있는 건식 세정에는 석회석(CaCO$_3$, limestone), 생석회(CaO, lime), 소석회(Ca(OH)$_2$, hydrated lime) 등 calcium을 다량 함유하는 흡수제가 매우 효과적이라고 알려져 있다. 따라서 이러한 흡수제와 SO$_2$dml 화학반응에 관하여 많은 연구가 수행되어 왔으나, 대부분의 연구는 SO$_2$와 석회석이 고온에서 진행되는 화학반응에서 관한 것이다.(중략)

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.3
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• pp.280-288
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• 1988

Lime requirement determination methods were experimentally compared and evaluated for the soils with different physico-chemical properties. The selected soils were mainly distributed in paddy field of Kangweon-Province; Anmi series from limestone region, Dongsong series from basalt region, Gyuam and Gangseo series from alluvial soil. The results were as follows: 1. Differences of soil lime requirement among seven methods ($CaCO_3$ incubation method, $BaCl_2$-TEA method, SMP-single buffer method, Double buffer method, Adams and Evans method, SMP-double buffer method, and O. R. D. method) were remarkably appeared. 2. Measuring lime values by $CaCO_3$ incubation method which is fixed on the basis of lime requirement, SMP-double buffer method was most acceptable for selected soils except Gyuam series, while $BaCl_2$-TEA method showed the highest value, and O. R. D. method was the lowest. 3. Exchangeable Al content of soils was neutralixed near to 70%, but 30% of extractable reached to neutralize when incubated with 100% lime equivalence. 4. Lime requirements based on exchangeable and extractable Al contents of soils were lower than that of $CaCO_3$ incubation method.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.4
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• pp.233-239
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• 2015

Monitoring of soil fertility and crop productivity in long-term application of fertilizers is necessary to use fertilizers efficiently. This study was conducted to investigate effects of continuous application of lime for rice cultivation from 1969 to 2014. The treatments were no lime treatments (N, NPK, NPKC, and NPKS) and lime treatments (N+L, NPK+L, NPKC+L, and NPKS+L). The application of lime in addition to N, NPK, and NPKC tended to increase pH, exchangeable Ca, and available $SiO_2$. The input of mean annual $1,170Mg\;ha^{-1}yr^{-1}$ of lime increased pH $0.0042yr^{-1}$, $0.0062yr^{-1}$, $0.0127yr^{-1}$, and $0.0041yr^{-1}$ in lime treatments (N+L, NPK+L, NPKS+L, and NPKC+L) compared with no treatments (N, NPK, NPKS, and NPKC), respectively. The mean annual Ca field balance varied from 169 to $561kg\;ha^{-1}yr^{-1}$in no treatments, from 871 to $1,263kg\;ha^{-1}yr^{-1}$ in lime treatments, indicating that Ca was accumulated in the soils. The mean annual Ca field balance in silicate fertilizer treatments (NPKS, NPKS+L) were higher than that of other treatments because silicate fertilizer included Ca component. Grain yield of rice had no significant differences between no lime treatments and lime treatments. Thus the application of lime led to changes in soil chemical properties but had no impact on the production of rice.

• Nuclear Engineering and Technology
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• v.24 no.3
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• pp.219-227
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• 1992

An experiment was conducted to determine the reaction of boric acid with lime and the drying of its product using a reactor-dryer. no characteristics of dried products were observed. The major chemical species of dried Products was calcium borate of 2CaO.B$_2$O$_3$. From the particle size distribution of the dried products, it was found that quick lime was better than slaked lime as an additive. The Ca/B mole ratio of reaction was determined to be 3/4 considering the cohesion and agglomeration properties of dried products. The flowability of dried products up to 8 wt% of water content was acceptable for transport process and to reduce drying time.

• Korean Journal of Heritage: History & Science
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• v.50 no.2
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• pp.40-61
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• 2017

This study investigated material characteristics of composition and variable strength measurement using physicochemical and petrographic analysis for lime-soil mixture barrier tombs of Guri Galmae site in Joseon Dynasty. The tomb barriers are composed mainly of microcrystalline calcite, quartz, feldspar and mica with lime matrix. The lime matrix shows compact sheet texture, and some samples show hydration aggregates with needle-shaped textures. Gypsum occurred as a secondary process where carbonization reactions were poor. Concentrations of CaO in the tomb barrier very widely ranged from 4.43 to 36.19 wt.%, specific gravity and absorption ratio of the materials show of 1.35 to 1.62 and 20.1 to 32.6%, respectively. As the rebound hardness, the materials ranged from 10.0 to 28.4 (mean 15.7). The values are higher in the $-90^{\circ}$ direction rather than in the $0^{\circ}$ direction with the consequence that the values indicate more strength toward the vertical direction. Difference in strength by directions was caused by the directions of the tomb barriers, which is related to the processes in each stage. In the tomb barriers, ultrasonic velocity and unconfined compressive strength ranged from 1,049.2 to 1,728.9m/s and under 5.00MPa, respectively. Variation patterns between the two are very similar in values. As the result of composition and strength, the materials of higher contents on CaO are higher in strength values. Generally, techniques and skills to make the lime-soil mixture barriers are interpreted as low qualities in relatively.