• Transactions of the Korean hydrogen and new energy society
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• v.16 no.1
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• pp.74-81
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• 2005

The heat treatment of serpentines for mineral carbonation was studied systematically. Crystallographic, spectroscopic and thermochemical properties were investigated for serpentines before and after heat treatment. Drastic weight loss due to the removal of hydroxy groupe(-OH) occupied in serpentine crystalline was revealed after heat treatment. In XPS results, MgO was founded at heat treated serpentine powders while Mg(OH) was observed at untreated serpentine powders. Metallic oxides originated from serpentine ingredients were regenerated by heat treatment.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.4
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• pp.76-80
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• 2015

In filler loaded paper, the size of the filler affects its strength, optical and surface properties. As the size of the filler increases, tensile strength and bulk usually increases, opacity decreases, and smoothness becomes worse. Pre-flocculation of GCC (grounded calcium carbonate) makes large diameter flocs at aqueous medium that consists of multiple GCC particles, but they collapse to 2-dimensional shape in dried paper and makes low bulk paper. The hybrid calcium carbonate (HCC) that was made by in-situ $CaCO_3$ formation between GCC in aqueous medium made high bulk paper without harming tensile strength, bulk, opacity, and smoothness. The GCC that has equivalent size as HCC failed to make high opacity and smoothness as much as HCC.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.4
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• pp.30-37
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• 2015

Needs for high ash loading in printing paper increase as green house gas (GHG) emission regulation becomes more stricter and pressure of lowering paper production cost increases. To meet the needs, a new type of filler was developed. The mixture of ground calcium carbonate (GCC) and calcium oxide was pre-floccuated with polyelectrolyte and further treated with carbon dioxide to form new calcium carbonate between GCCs. The final products were called as hybrid calcium carbonate (HCC), and its properties were compared to the GCC and the pre-flocculated GCC. Results showed increase in tensile, smoothness, opacity, and bulk for HCC.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.146-151
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• 2001

Several design parameters for a 100 kW molten carbonate fuel cell stack was described. Approximately 170 cells are required to generate 100 kW at a current density of $125\;mA/cm^{2}$ with $6000\;cm^{2}$ cells. An overall heat balance was calculated to predict exit temperature. In order to limit the stack temperature in the range of $600-700^{\circ}C$, current load cannot exceed $75\;mA/cm^{2}$ at atmospheric operation. The 100 kW power is expected only under pressurization. Recycle of cathode gas by more than 50% is recommended to run the stack at $125\;mA/cm^{2}$ and 3 atm. Manifolds should be designed based on gas flow rates for the suggested operating condition.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.2
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• pp.159-165
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• 2000

This study was investigated the environment of waste shells such as oyster, cockle and paphia on southern shore in korea and established the recycling method to prevent the environmental pollution, etc. The waste shells were reclaimed at public shore illegally or leaved on the surroundings of shore. The origin mechanism, XRD and TG-DTA analyses were performed to effective recycling of waste shells, and the optimal recycling method was preparation of the calcium carbonate. In this work, calcium carbonate and lime fertilizer of granular shape were prepared using the waste shell.

• Transactions of the Korean hydrogen and new energy society
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• v.17 no.1
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• pp.109-116
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• 2006

The heat treatment characteristics of natural talc sample was investigated in diverse analytical view point. The mass decrease comes to heat treatment was resulted by the continuous and the discontinuous process and the obtained result show very similar two step profiles with 8.9 % mass decrease. The dehydroxylation of -OH groups contained talc crystal was analyzed by spectroscopic method and the crystallographic variations was also observed after heat treatment. According to XPS result, the magnesium hydroxide($Mg(OH)_2$) of untreated talc powder changed to magnesium oxides(MgO) after heat treatment.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.89-91
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• 2012

The purpose of this study is to investigate the mechanical property and carbonation resistance of concretes using surface treated lightweight aggregate. In order to evaluate mechanical property and carbonation resistance, slump, compressive strength, and carbonation depth are tested. Slump of concretes using surface treated lightweight aggregate measured 120~125mm, which are lower than slump of NWAC. Compared to compressive strength of NWAC, compressive strength of concretes using surface treated lightweight aggregate showed a level of 82.8~95.9%. In carbonation resistance test, carbonation depth of concretes using surface treated lightweight aggregate measured 10.2~11.3mm, which are lower than carbonation depth of NWAC. As a result, it is found that compressive strength is decreased slightly but carbonation resistance is improved, in case of using surface treated lightweight aggregate.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.53-56
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• 2008

An ejector is a fluid machinery to be utilized for mixing fluids, maintaining vacuum, and transporting them. The Ejector is applied for a variety of industrial fields such as refrigerators and power plants. It is adopted to recycle anode off gas safely in 5kW Molten Carbonate Fuel Cell system of KEPRI(Korea Electric Power Research Institute). The ejector is placed at mixing point between the anode off gas and the cathode off gas or the fresh air. In this study, the entrainment ratio is measured according to the diametrical ratio of nozzle to throat. In addition, the performance curve of the ejector and the differential pressure in diffuser is observed.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.413-416
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• 2004

매립장 침출수로 인해 오염된 매립장 주변 지하수 정화를 위한 실내실험을 실시하였다. 오염물로는 대표적 염화용제인 TCE와 PCE, 그리고 중금속인 As, Cd, Cr, Pb에 대하여 Air-sparging, 오존 산화법, 화학적 처리방법에 의한 정화효율 실험을 실시하였다. Air-sparging은 TCE, PCE에서 높은 제거효율을 가졌으며, 오존 산화법은 Cr, Pb에서 제거 효율이 좋았다. 반응제를 첨가한 공침방법의 경우, 모든 중금속에 대하여 소석회 첨가시 매우 높은 제거효율을 보였으며, As는 황산제일철에서, Cd, Cr, Pb는 탄산칼슘과 제올라이트 첨가시 높은 제거효율을 나타내었다. 실험결과로부터, 유기오염물과 중금속이 혼합되어 나타나는 매립장 주변 오염 지하수의 경우 휘발성 유기오염물의 제거를 위해서는 폭기방법이, 중금속의 경우에는 공침방법에 의해 수산화물, 탄산염으로 만들어 고형물로 처리하는 방법이 제거효과가 좋은 것으로 나타났다.

• Korean Journal of Food Science and Technology
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• v.23 no.6
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• pp.695-701
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• 1991

Spent layer breast meat and leg meat samples washed with 0.05 M sodium bicarbonate solution and 0.04 M phosphate buffer(pH 8.3) showed decreases in heat denaturation temperature indicating the destabilization of myofibrillar proteins. The destabilization was attributed to the solubilization of 95 Kdalton and 55 kdalton proteins from the myofibrils observed in gel-electrophoretograms. Transmission electron microscopy further indicated the breakage of Z-lines.