• 한국세라믹학회지
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• 제53권2호
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• pp.222-226
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• 2016

The synthesis of pure calcium carbonate nanocrystals was achieved using a simultaneous injection method to produce nano particles of uniform size. These were characterized using scanning electron microscopy and powder X-ray diffraction. The nano particles were needle-shaped aragonite polymorphs, approximately 100-200 nm in length. The aragonite polymorph of calcium carbonate was prepared using aqueous solutions of $CaCl_2$ and $Na_2CO_3$, which were injected simultaneously into double distilled water at $50^{\circ}C$ and then allowed to react for 1.5 h. The resulting whisker-type nano aragonite with high aspect ratio (30) is biocompatible and potentially suitable for applications in light weight plastics, as well as in the medical, pharmaceutical, cosmetic and paint industries.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.719-722
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• 2003

This paper presents the development of reservoir characterization model equipped with parallelized genetic algorithm, and its application for a heterogeneous reservoir system with integration of the well data and multi-phase production data. A parallel processing method performed by PC-cluster was applied to the developed model in order to reduce time for an inverse calculation. By utilizing the developed model, we performed the inverse calculation with the production data obtained from three layered reservoir system to estimate porosity and permeability distribution. As a result, the pressures observed at well almost identical to those calculated by the developed model. Also, it was confirmed that parallel processing could be applied for reservoir characterization study efficiently.

• Korean Chemical Engineering Research
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• 제55권4호
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• pp.443-455
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• 2017

This article provides an exclusive overview of the synthesized aragonite precipitated calcium carbonate and its applications in various fields. The last decade has seen a steady increase in the number of publications describing the synthesis, characterization and applications of calcium carbonate morphologies. Mainly, two kinds of processes have been developed for the synthesis of aragonite precipitated calcium carbonate under controlled temperature, concentrations and aging, and the final product is single-phase needle-like aragonite precipitated calcium carbonate formed. This review is mainly focused on the history of developed methods for synthesizing aragonite PCC, crystal growth mechanisms and carbonation kinetics. Carbonation is an economic, simple and ecofriendly process. Aragonite PCC is a new kind of functional filler in the paper and plastic industries, nowadays; aragonite PCC synthesis is the most exciting and important industrial application due to numerous attractive properties. This paper describes the aragonite PCC synthetic approaches and discusses some properties and applications.

• 자원환경지질
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• 제43권6호
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• pp.603-613
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• 2010

남해 대륙붕 도미분지는 제주분지의 북동단에 위치하는 지역으로 동해의 울릉분지와 인접해 있으며 그 발달시기에 대한 연구가 지속적으로 수행되고 있다. 본 연구에서는 도미퇴적분지의 해석에 적합한 탄생파자료 전산처리 모듈을 시험하고 매개변수를 도출하였다. 도미분지 천부 퇴적층인 제3기 층의 경우 반사파 신호의 연속성 향상과 페그레그(peg-leg) 다중반사파 억제가 요구되었고 이를 위하여 중합 층서속도분석(Horizon Velocity Analysis, HVA)과 표면-연관 파동방정식 다중반사파 제거(Surface Relative Wave Equation Multiple Rejection, SRWEMR)모듈을 조합하여 중합단면의 품질을 제고하였따. 연구결과 제작된 도미분지 탄성파 중합단면에서 퇴적층서가 구분되는 부정합면이 인지되었다. 분지의 발달양상 규명에 적절한 중합단면이 도출되었고 다중반사파의 억제로 백악기 기반암의 해석에 도움이 되었다. 본 연구를 통하여 검증된 전산처리과정은 도미분지와 인근 소라분지, 북소라분지의 탄성파 자료 전산처리 품질의 규격화 및 처리속도 향상에 기여할 것으로 기대된다.

• 한국지구과학회지
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• 제29권7호
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• pp.523-530
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• 2008

전통적 약재가공법인 초쉬법으로 수치된 적철석 약광물의 광물조성과 원소성분 변화를 고찰하였다. 적철석은 $650^{\circ}C$와 $900^{\circ}C$에서 각각 5회씩 초쉬법으로 수치되었다. 약재로 가공된 적철석은 수용액에서 원소 용출실험이 수행되었다. 초쉬법 수치에 따른 적철석의 광물상 변화는 없었다. 또한 $650^{\circ}C$와 $900^{\circ}C$에서 수치횟수와 원소 용출량의 변화 경향이 없는 것으로 보아 전통적 초쉬법에 의한 적철석의 약재 가공 효과는 불분명한 것으로 보인다. 그러나 가열된 약재를 식초에 담금질하는 가공법은 적철석을 부드럽고 분쇄되기 쉬운 약광물로 변화시키는 효과가 있다.

• 한국재료학회지
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• 제16권8호
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• pp.497-502
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• 2006

Recently, many attention have been focused on illite as a material for the well-being industry. Illite contains various kinds of iron bearing materials and they restrict their usage. In this study, Fe impurities in the illite produced in Yeongdong-gun, Chungcheongbuk-do were characterized and their removal experiments were performed. According to the characterization of illite raw ore, it contained 1.54 wt.%$Fe_2O_3$ due to the existence of iron oxide($Fe_2O_3$) and pyrite($FeS_2$). The raw ore was crushed into 3 mm or less using cone crusher and then ground by rod mill for the liberation of impurity mineral. For the removal of iron bearing minerals, an acid treatment, a flotation, a magnetic separation, and a flotation combined with magnetic separator were performed respectively. When the illite raw ore was treated with magnetic separation and various kinds of acid, 1.54wt.%. $Fe_2O_3$ content was reduced to 0.78 and 1.0 wt.%, respectively. On the other hand $Fe_2O_3$ content was reduced to be 0.52 wt.% after flotation. These results indicate that iron bearing minerals cannot be reduced below 0.3wt.%$Fe_2O_3$. However, combination of magnetic separation and flotation enable us to get 0.24wt.% of illite concentrate. It is concluded that, for the refinement of illite from Yeongdong-gun, the flotation combined with magnetic separation is good for high purity illite.

• Journal of Evidence-Based Herbal Medicine
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• 제3권1호
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• pp.1-7
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• 2010

While herbal medicine including mineral herbal medicine mostly provides microelements to the human body thanks to abundant metallic elements, its harmfulness has been raised due to elements of heavy metals. Harmfulness of mineral herbal medicine needs to be analyzed quantitatively as well as qualitatively so that specificity of herbal medicine including mineral herbal medicine can be reflected. Consequently, the following aims should be set up to mineral herbal medicine, REALGAR, standard processing of REALGAR and the standards of processed drugs should be secured. On the basis of the results of this study, the reasonable measures to develop the processing method and the test method for heavy metals were presented. Such measures are expected to give the following results. First, consumers may take food and medicine without anxiety, and food and medicine may be effectively managed, and the national service may be improved, and also safety against heavy metals may be publicized. Second, as the principal ingredients and microelements of mineral herbal medicine are qualitatively analyzed, such results are expected to contribute to the advance of national analytics for herbal medicine.

• Korean Chemical Engineering Research
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• 제55권3호
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• pp.279-286
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• 2017

This review paper evaluates different kinds of synthesis methods for calcite precipitated calcium carbonates by using different materials. The various processing routes of calcite with different compositions are reported and the possible optimum conditions required to synthesize a desired particle sizes of calcite are predicted. This paper mainly focuses on that the calcite morphology and size of the particles by carbonation process using loop reactors. In this regard, we have investigated various parameters such as $CO_2$ flow rate, Ca $(OH)_2$ concentration, temperature, pH effect, reaction time and loop reactor mechanism with orifice diameter. The research results illustrate the formation of well-defined and pure calcite crystals with controlled crystal growth and particle size, without additives or organic solvents. The crystal growth and particle size can be controlled, and smaller sizes are obtained by decreasing the Ca $(OH)_2$ concentration and increasing the $CO_2$ flow rate at lower temperatures with suitable pH. The crystal structure of obtained calcite was characterized by using X-ray diffraction method and the morphology by scanning electron microscope (SEM). The result of x-ray diffraction recognized that the calcite phase of calcium carbonate was the dominating crystalline structure.

• 한국자원리싸이클링학회:학술대회논문집
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• 한국자원리싸이클링학회 2005년도 춘계임시총회 및 제25회 학술발표대회
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• pp.206-208
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• 2005

• 한국자원리싸이클링학회:학술대회논문집
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• 한국자원리싸이클링학회 2005년도 춘계임시총회 및 제25회 학술발표대회
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• pp.141-144
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• 2005