• 한국세라믹학회지
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• 제53권1호
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• pp.7-12
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• 2016

In this paper, we have developed a simple, new and economical carbonation method to synthesize a pure form of aragonite needles using dolomite raw materials. The obtained aragonite Precipitated Calcium Carbonate (PCC) was characterized by XRD and SEM, for the measurement of morphology, particle size, and aspect ratio (ratio of length to diameter of the particles). The synthesis of aragonite PCC involves two steps. At first, after calcinated dolomite fine powder was dissolved in water for hydration, the hydrated solution was mixed with aqueous solution of magnesium chloride at $80^{\circ}C$, and then $CO_2$ was bubbled into the suspension for 3 h to produce aragonite PCC. Finally, aragonite type precipitated calcium carbonate can be synthesized from natural dolomite via a simple carbonation process, yielding product with average particle size of $30-40{\mu}m$.

• 에너지공학
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• 제27권1호
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• pp.51-58
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• 2018

In this paper, we reported that the influence of advanced functional mineral filler calcium carbonate ($CaCO_3$) extracted from oyster shell waste, which are rich mineral sources of $CaCO_3$. Oyster Shells, available in abundance, have no eminent use and are commonly regarded as waste. Their improper disposal causes a significant level of environmental concern and also results in a waste of natural resources. Recycling shell waste could potentially eliminate the disposal problem, and also turn an otherwise useless waste into high value added products. Oyster shell waste calcination process to produce pure lime (CaO) which have good anti-microbial property for waste water treatment and then focuses on its current applications to treat the coffee waste and its effluents for biological treatment and utilization as a fertilizers.

• 한국환경보건학회지
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• 제45권6호
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• pp.561-568
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• 2019

Objectives: The most commonly detected heavy metals in rocks and soils, including Pb, Cd, Cu, Fe, Mn and As, are representative pollutants discharged from abandoned mines and have been listed as potential sources of contamination in drinking water. This study focused on increasing the removal efficiency of heavy metals from drinking water resources by surface modification of natural adsorbents to reduce potential health risks. Methods: Iron oxide coating and graft polymerization with zeolites and talc was conducted for bipolar surface modification to increase the combining capacity of heavy metals for their removal from water. The removal efficiency of heavy metals was measured before and after the surface modification. Results: The removal efficiency of Pb, Cu, and Cd by surface modified zeolite showed 100, 92, and 61.5%, respectively, increases compared to 64, 64, and 38% for non-modified zeolite. This implies that bipolar surface modified natural adsorbents have a good potential use in heavy metal removal. The more interesting finding is the removal increase for As, which has both cation and anion characteristics showing 27% removal efficiency where as non-modified zeolite showed only 2% removal. Conclusions: Zeolite is one of the most widely used adsorptive materials in water treatment processes and bipolar surface modification of zeolite increases its applicability in the removal of heavy metals, especially As.

• 한국환경보건학회지
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• 제24권1호
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• pp.87-97
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• 1998

This study was performed to investigate the Natural mineral water quality at 47 sites in Chonnam area, samples were collected spring, summer, fall, winter for a seasonal variation in 1996. The results obtained were summarized as follows 1. The mean of F, pH, HCO$_3$, NO$_3$ -N were 0.19 mg/l, 6. 9, 34.99 mg/l, 1.40 mg/l and those of Na, K, Ca, Mg were 12.1 mg/l, 1.2 mg/l, 7.7 mg/l, 2.1 mg/l respectively. 2. The contents of F were reasonable at Multonggol as 1.35 mg/l and Yongbayui as 0.57 mg/l respectively, but there is no detected at Sidong and detected below 0.1 mg/l at Gubongsan, Hansansa area. 3. According to the geological effect, the content of F was showed higher in granite than in tuff, and index of pH was higher in tuff than in andesite, and content of HCO$_3$ was higher in andesite than in granite. 4. The K and O values were used as index of healthy and delicious water. As a result, thirtyfive sites(74.5%) was decided as healthy and delicious water. 5. The contents of NO$_3$-N were detected over 5 mg/l at Sukchonsa, Gajanggol, Yudalsan, Muchang, Kisan.

• 자원환경지질
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• 제41권5호
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• pp.497-507
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• 2008

본 연구는 국내 5대 수출 품목 중 하나이며, 국내 주요 수출품의 원자재로서 지속가능한 자원관리의 파급효과가 큰 철강을 대상으로 히든플로우와 물질집중도를 MIPS방법론을 이용하여 정량화하였다. 2005년에 4.8천톤의 철강재와 17.6백만달러(2000년 기준)의 부가가치를 생산하기 위해 71백만톤의 윈재료와 18백만Toe의 에너지를 사용하였다. 이러한 원재료와 에너지사용으로 인한 천연자원사용량은 TMR(total Material Requirement, 총물질요구량) 245백만톤, water 1524백만톤, air 34백만톤이었다. 그리고 material intensity, 즉 철강재 1톤을 생산하기 위해서 TMR 4.3톤, water 28톤, air 0.5톤의 자연자원이 사용되었다.

• 한국환경보건학회지
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• 제33권6호
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• pp.517-521
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• 2007

To assess possible risks from the consumption of drinking water from various sources, a survey of the microbiological quality of tap water, commercial bottled drinking water which is exploited from natural mineral water, and natural spring water was conducted. A total of 4 different brands of commercial bottled drinking water, and 4 types of spring water from different sources, and tap water from 4 private houses were tested for four index microorganisms, and the microbial quality changes of the water during the storage at room temperature or refrigerated temperature for 7 days. Aerobic plate counts of all of the initial water samples were still within 100 CFU/ml (drinking water standard of Korea). Total coliforms, fecal coliforms, and E. coli were not detected in all of the water samples at initial. However, aerobic plate counts of three types of spring water and three types of bottled drinking water stored at room temperature showed higher levels than the standards in 5 days. Total coliforms were detected in three types of spring water after one day's storage at room temperature, and in one type of bottled drinking water after 5 days' storage. These results indicate that some of the spring water surveyed are not safe to drink, and the spring water and bottled drinking water after opening the lid should not be stored at room temperature, if they are used for drinking.

• 한국세라믹학회지
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• 제51권2호
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• pp.72-81
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• 2014

The main mineral phases of natural hydraulic lime (NHL) as a hydraulic lime binderare $Ca(OH)_2$, $C_2S$, $C_3S$, $C_3A$, and $SiO_2$ residues. Also, NHL has the characteristic of setting and hardening by a hydration reaction with water and by carbonation reactions with carbon dioxide from the air. In this study, in an effort to investigate changes of the mineral phases by NHL hydration and carbonation reactions, transitions of mineral phases and the microstructures of hardened pastes were analyzed by XRD, DSC, SEM, and by pore size distributions using domestic and foreign-sourced NHL pastes after curing at 1, 3, 7, and 28 days. On the basis of the analysis results, it was confirmed that domestic low-grade limestone can be used for the manufacturing of NHL. The main hydration mineral phases were $Ca(OH)_2$, $CaCO_3$, $C_2S$, and $SiO_2$ residues, while in the case of foreign-sourced NHL, a small amount of an aluminium hydration phase formed. Also, the $CaCO_3$ content after the carbonation reaction increased with an increase in the curing time. After hydration for 28 days, NHL containing considerable amounts of $C_2S$ and $C_3S$ showed higher carbonation ratios than others types.

• 지질공학
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• 제8권3호
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• pp.247-259
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• 1998

먹는샘물은 국민의 건강과 직결될 뿐 아니라 귀중한 지하수자원이라는 점에서 엄격한 품질기준과 사후관리가 요구된다. 본 연구에서는 대보화강암(20개)과 불국사화강암(4개) 지역에 분포하는 먹는샘물 업체를 대상으로 원수의 수질특성을 수리화학적인 측면에서 해석하였다. 대보화강암과 불국사화강암 지역에 분포하는 먹는샘물 업체의 원수의 수질특성은 수리화학적으로 유사한 경향을 보이지만 상이한 부분도 있다. 수소이온농도, 전기전도도, 총고용물질, 경도, 양이온과 음이온의 함량은 대보화강암 지역이 불국사화강암 지역보다 높게 나타난다. 양이온 중에서 대부분은 Ca>Na>Mg>K의 순으로 함량비를 나타내며 음이온 성분의 함량은 $HCO_3>SO_4>Cl>K$의 순을 보인다. 화강암지역에서 $Ca-Na-HCO_3$ 유형이 가장 우세하며 Ca함량이 가장 높은 현상은 화강암에 풍부하게 포함되어 있는 사장석류의 용해작용에 기인하기 때문인 것으로 보인다. 대보화강암 지역에서는 $Ca-HCO_3(0.84),{\;}Mg-HCO_3(0.81),{\;}SiO_2-Cl(0.74),{\;}Na-HCO_3(0.70)$ 등이 비교적 높은 상관관계를 보이며, 불국사화강암 지역의 경우 K-Mg(0.93), $K-HCO_3(0.92)$, Mg-Cl(0.92), $Cl-HCO_3(0.91)$, K-F(0.90) 등이 다소 높은 상관관계를 보인다. 실리카 상들을 제외한다면 대부분의 지하수는 방해석의 포화도에 가장 근접한 상태를 보여 주며 돌로마이트, 석고, 형석에 대하여는 불포화정도가 다소 큼을 나타낸다. 실리카의 활동도가 증가하는 동안 K, Na같은 알칼리원소의 활동도와 pH는 크게 증가하지 않았는데 이는 장석류로부터의 용해작용 이외에 석영과 같은 실리카상들의 용해작용에 의하여 규산이 어느 정도 공급되었음을 의미한다. 전반적으로 보아 화강암 지역의 지하수가 암석내에 가장 풍부하게 존재 하는 장석류에 대하여 아직도 불포화 상태에 있기 때문에 pH의 증가와 함께 장석류와의 반응이 계속 진행될 수 있을 것으로 예상된다.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.428.2-428.2
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• 2002

The present study was performed to examine the effects of oral administrations of Panax ginseng(PG) and P. quinquefolium(PQ) roots on hemodynamics and body temperature in healthy young men, since it was claimed that PG raises heat whereas PQ lowers heat by some ethnopharmacologists. The 42 healthy young male volunteers were divided into live groups. which were treated with mineral water(control), each high (9.0 g) and low (4.5 g) dose of PG and PQ. (omitted)

• 생태와환경
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• 제45권3호
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• pp.271-277
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• 2012

본 연구에서는 D. magna의 배양배지로서의 국내 자연수의 적절성을 평가하기 위하여, Elendt M4 배지에서 생산된 태어난 지 24시간 미만 된 어린 D. magna를 Elendt M4 배지, 탈염소 수도수 및 먹는 샘물에 21일 동안 노출시켜 생존율 및 번식능력을 평가하였다. 대조배지인 Elendt M4 배지와 먹는 샘물에서 배양한 D. magna는 어미의 생존율, 첫 배를 생산하는 시기, 생존한 어미 당 생산된 총 어린 물벼룩 평균수, 생존한 어미 당 생산된 죽은 어린 물벼룩 평균수는 2회의 번식시험 모두에서 Jonczyk과 Gilron (2005) 및 OECD No. 211, Daphnia magna Reproduction Test 지침서(OECD, 2008)의 기준을 벗어나지 않았다. 그러나 탈염소 수도수에서 배양을 한 경우에는 2번의 번식시험 모두 어미의 사망률이 20% 이상으로, 배양 13일, 15일, 18일에 사망된 개체가 관찰되었다. D. magna는 경도가 80 mg $CaCO_3\;L^{-1}$ 이상인 물에서 사용을 추천하고 있으나, 본 연구에서 사용된 탈염소 수도수의 경도는 50~53 mg $CaCO_3\;L^{-1}$ 이었다. 탈염소 수도수에서 나타난 지연된 사망률은 배양배지의 급격한 경도 차이에 의한 영향으로 판단된다. 그러므로 국내의 자연수(지하수, 표면수, 탈염소 수도수 등)를 사용하여 D. magna를 배양할 경우, 배양배지의 경도를 100 mg $CaCO_3\;L^{-1}$ 이상 강화시켜 사용하는 것이 필요하다. 그리고 궁극적으로는 국내에 서식하는 토착 물벼룩류를 대상으로 국내 수 환경에 적합한 시험생물을 개발하는 국가적인 연구가 필요하다고 사료된다.