• The Journal of the Convergence on Culture Technology
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• v.5 no.1
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• pp.333-339
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• 2019

The purpose of this study is to clarify the effect of magnesium water on the cognitive function, concentration and performance of bowling players. The total number of subjects in this study was 42, and changes in blood magnesium concentration, cognitive ability, concentration and performance were identified during the four-week experiment period. Data distribution was analyzed using SPSS18.0 with Normality test and Repeated measure two way ANOVA. Studies show that the concentration of magnesium in the blood of bowling players has changed with the intake of magnesium drinks, and that the concentration of magnesium in the blood has a proportional relationship with the cognitive function, concentration and performance.

• Resources Recycling
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• v.16 no.2 s.76
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• pp.3-11
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• 2007

It is to review the current status of magnesium smelting. Raw materials for magnesium source, worldwide production and producers of metallic magnesium, Korean magnesium markets and some important extraction technologies were reviewed. The magnesium extraction technologies were described according to the two major reduction methods: the fused salt electrolysis and the thermal reduction method. Also, the research on the extraction of magnesium from magnesite which has been being carried out at KIGAM was briefly introduced with discussing the related topics on the recycling of the chlorine and the hydrogen chloride gas used in the process.

• Fire Science and Engineering
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• v.25 no.5
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• pp.69-75
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• 2011

It was performed to test the combustive properties of low density polyethylene and ethylene vinyl acetate (LDPE-EVA) composite by the addition of magnesium hydroxide. Flame retardant of natural magnesium hydroxide was added to the mixture of LDPE-EVA in 40 to 80 wt% concentration. The composite was compounded to prepare specimen for combustive analysis by cone calorimeter (ISO 5660-1). Comparing with virgin LDPE-EVA, the specimens including the magnesium hydroxide had lower flashover possibility. It is supposed that the combustive properties in the composites decreased due to the endothermic decomposition of magnesium hydroxide. The specimens with magnesium hydroxide showed both the lower total heat release rate (THR) and lower CO production rate than those of virgin polymer. As the magnesium hydroxide content increases, the total smoke release (THR) and smoke extinction area (SEA) decreased.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.142-142
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• 2015

아연-마그네슘 합금은 마그네슘 첨가로 인한 뛰어난 내식성과 아연의 자원 고갈에 대한 갈등을 해소할 수 있다는 장점을 가지고 있으므로 차세대 강판 도금 소재로서 주목받고 있다. 그러나 아연-마그네슘의 도금 공정은 상대적으로 높은 융점을 지닌 마그네슘 첨가로 인해 기존의 아연 도금 공정에 비해 고온에서 이루어지므로 용융 금속에 의한 도금 설비의 빠른 손상이 발생하게 된다. 따라서 이와 같이 고온 환경에서도 사용 가능한 수준의 내구성을 지닌 소재의 개발이 반드시 필요한 상황이다. 선행 연구에 의하면 Mo은 아연-마그네슘 용탕에서 우수한 내침식 특성을 보이는 것으로 확인되었지만 pure Mo의 경우 고온 산화에 취약한 단점을 가지고 있어 내구성에 한계를 보인다. 따라서 본 연구에서는 이러한 문제를 해결하기 위해 pack cementation 공정을 통해 Mo 표면에 내산화 특성이 우수한 Mo 금속간화합물($MoSi_2$, $Mo_3Si$, $Mo_5SiB_2$)을 형성시켰고 이를 대상으로 아연-마그네슘 용탕에 대한 내산화 거동을 평가하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.125.1-125.1
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• 2016

마그네슘 합금은 소재 특성상 표면처리가 필수불가결하다. 금속의 다양한 표면처리 방법 중 마그네슘 합금은 크게 화학적 반응을 이용해 산화막을 생성해 피막을 올리는 화성처리법과, 전해액 내에 침지시켜 전기를 걸어주어 금속 표면에 플라즈마 아크를 통해 산화막을 생성하는 PEO공법 두 가지 방법이 있다. 본 연구에서는 마그네슘 합금 소재에 PEO공법을 적용한 산화피막의 공정 변수에 따른 특성을 SEM, EDS, SST, potentiodynamic polarization 등으로 분석하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.05a
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• pp.153-153
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• 2009

첨가제를 사용한 피로인산구리 도금욕에서 마그네슘 합금상에 직접 구리도금을 실시하였다. 피로인산구리 도금욕에서 첨가제가 마그네슘 합금 도재에 미치는 영향에 대하여 연구하였다. 연구에 따른 첨가제를 포함하는 피로인산구리 도금욕에서 구리도금층의 적합성을 확인하기 위하여 기존의 마그네슘 모재에 구리를 도금하기 위한 방법인 징케이트 처리 후 시안구리도금욕에서 구리도금하는 방법과 비교 고찰 하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.05a
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• pp.307-307
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• 2012

마그네슘합금은 넓은 분야에서 사용되고 있지만 높은 산화성과 화학반응성 때문에 표면처리를 하지 않고서는 사용 할 수 없다. 따라서 본 과제에서는 개발 중인 신 마그네슘 합금소재의 부식 및 피막특성을 관찰하기 위해 염수분무시험, 염수침지, 분극 시험 및 도장밀착성 내식성 시험을 시행하였다. 이 결과는 새로 개발되는 신 마그네슘 합금 성분 및 함량 결정의 기초 데이터가 될 것이다.

• Clinical and Experimental Pediatrics
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• v.52 no.10
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• pp.1140-1146
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• 2009

Purpose:The pathophysiology of magnesium, the second highest common compound in humans, is still unclear, especially in preterm babies. We accessed the association between total magnesium (tMg), ionized Mg (iMg), and gestational age (GA) and that between serum magnesium (sMg) and intraventricular hemorrhage (IVH) in preterm babies. Methods:In all, 119 inborn preterm infants admitted between July 2006 and February 2008 were divided into the IVH group (19) and the control group (100) and were prospectively analyzed. TMg, iMg, pH, total calcium (tCa), and ionized Ca (iCa) levels were determined immediately after delivery or within 3 hours after birth, and their correlation with GA were investigated. Results:TMg was not correlated with GA, tCa, iCa, and pH. IMg was correlated with tMg (r=0.288, P=0.002) and iCa (r=0.212, P=0.021); however, it was not correlated with GA and pH. Mean GA and birth weight were significantly lower (P=0.002) and smaller (P=0.030) in the IVH group. Mean sMg was higher in the IVH group ($2.5{\pm}0.9mg/dL$) than in the control group ($2.1{\pm}0.6mg/dL$) (P=0.021). SMg was a risk factor even after logistic regression analysis (OR, 2.798; 95% C.I., 1.265-6.192; P=0.011). Conclusion:In less than 37-week-old preterm babies, tMg and iMg were similar, regardless of GA. High sMg may be a risk factor for IVH in premature babies, regardless of their exposure to antenatal magnesium.

• Resources Recycling
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• v.16 no.5
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• pp.8-12
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• 2007

Anhydrous magnesium chloride, dehydration product from magnesium chloride hydrate is a general raw material to prepare electrolytic magnesium. However, the dehydration is not trivial and can be accompanied by hydrolysis leading to the production of undesirable hydroxy chloride compounds of magnesium. Therefore, dehydration process is actually the most complicated and hardest in the electrolysis methods for the production of magnesium. In this work, the influence of dehydrating temperature has been studied at the temperature range from $200^{\circ}C$ to $600^{\circ}C$ in air and HCl gas atmosphere individually to compare the results. With increasing of dehydration temperature MgOHCl and MgO were obtained in air. On the other hand, when the temperature was increased above $300^{\circ}C$ anhydrous magnesium chlorides were prepared in HCl gas atmosphere. Anhydrous magnesium chloride was formed at near $300^{\circ}C$ and completely crystallized at about $500^{\circ}C$. All of the HCl used as atmosphere gas in the dehydration was recovered as hydrochloric acid solution at a water vessel up to 41% by weight at $20^{\circ}C$.

• Resources Recycling
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• v.15 no.2 s.70
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• pp.32-36
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• 2006

Magnesium has been used as light and functional material, and its demand is increasing as a material for automobile engine and for mobile phone or notebook PC case. Fused salt electrolysis and thermal reduction are regarded as main methods for the extraction of magnesium, and choice for the method is firstly according to raw material. In this study, magnesium metal is obtained by an electrolysis of magnesium chloride. Two types of fused salt mixtures were used as electrolyte and electrolyzed at 7V with a graphite anode having the same depth, and their results were compared with each other. A mixed salt of $KCl/NaCl/MgCl_2$ was the more effective than $KCl/NaCl/CaCl_2/CaF_2/MgCl_2$ in current efficiency through the experiments at $760^{\circ}C$. Purity of the prepared magnesium metal was above 98%. Some basic data for scale-up of the magnesium electrolysis equipment, which would be necessary for a commercialization, could be obtained.