• 자원리싸이클링
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• 제17권1호
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• pp.80-87
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• 2008

주요 성분으로서 철$(Fe^{2+}/Fe^{3+}=1.03)$ 47g/L, 니켈; 23.5g/L, 0.90M $H_2SO_4$의 조성을 갖는 철-니켈 합금 스크랩의 황산 침출액으로부터 시멘테이션법과 용매추출법으로 니켈과 철 이온을 분리하는 연구를 수행하였다 침출액으로부터 니켈 이온의 시멘테이션을 위하여 철 분말이 환원제로 사용되었다. $60{\sim}80^{\circ}C$에서 4.0 당량의 철 분말을 투입하였을 때 니켈 이온의 환원율은 $17{\sim}20%$에 불과하였으며, 이것은 니켈 이온의 환원석출이 $Fe^{3+}$의 환원반응과 황산의 중화반응이 완료된 후에 시작되었기 때문이다. 이로부터 주성분으로 $Fe^{3+}$를 함유하고 있는 침출액으로부터 니켈 이온의 분리회수에 있어서 시멘테이션은 비효율적임이 확인되었다. D2EHPA를 추출제로 사용하는 철 이온의 용매추출을 위하여 $Fe^{2+}$는 $Fe^{3+}$로 전환시켰다. 1.2 당량의 35% $H_2O_2$를 첨가함으로서 침출액에 존재하는 모든 $Fe^{2+}$는 $Fe^{3+}$로 산화되었다. 20 vol.% D2EHPA를 사용하여 cross-current 방식으로 침출액(23.5 g/L $Fe^{3+}$)으로부터 $Fe^{3+}$의 용매추출을 행하였을 때, 4단 추출에서 99.6%의 $Fe^{3+}$를 추출하여 제거할 수 있었으며 순도가 98.5%인 황산니켈 용액이 얻어졌다

• 자원환경지질
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• 제33권1호
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• pp.1-18
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• 2000

Lens shaped and stratiform titanomagnetite orebodies in the Boreumdo iron mine are closely associated with amphibolite which intruded into Precambrian metasediments. Mineralogical and petrochemical analyses of amphilbolite and titanomagnetite ores were carried out in order to interpret the origin of amphilbolite and the genesis of titanomagnetite ore deposits. Amphibolites belong to orthoamphilbolite interms of Niggli value and mineralogy, and are characterized by the occurrence of relict olivine. The amphilbolites responsible for titanomagnetite mineralization have extremely high content of $TiO_2$, ranging from 2.12 to 4.59 wt.% with the average value of 3.43 wt.%. Amphibole minerals in amphibolites are consist mainly of calcic amphiboles such as hornblende, ferroan pargasitic hornblende and tremolite. Most plagioclases belong to andesine ($An_{30-50}$\ulcorner). The metamorphic temperature and geobarometric pressure which are calculated by the calcic amphibole-plagioclase geothermometer and calcic amphilbole geobarometer are estimated to be 537$^{\circ}C$~579$^{\circ}C$(avg. 555$^{\circ}C$) and 2.9~6.6 kbar (avg. 4.5 kbars), respectively. It shows a typical amphibolite facies. Based on the mineral chemistry and petrochemisty of amphibolites and iron ores which are composed mainly of titanomagnetite and ilmenite in the Boreumdo iron mine, the titaniferous oxide melts could be immiscibly separatd from the titaniferous ultrabasic magma. The genesis of the Boreumdo titanomagnetite ore deposits are analogous to the Soyeonpyeongdo and Yonchon iron ore deposits in terms of their mineralogy, mineral chemistry and geologic setting.

• 한국지하수토양환경학회지:지하수토양환경
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• 제19권1호
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• pp.63-69
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• 2014

This paper presents the feasibility of using different iron oxides (microscale hematite (HT), microscale magnetite (MT), and nanoscale maghemite (NMH)) in enhancing nitrate reduction by zero-valent iron (Fe(0)) under two solution conditions (artificial acidic water and real groundwater). Addition of MT and NMH into Fe(0) system resulted in enhancement of nitrate reduction compared to Fe(0) along reaction, especially in groundwater condition, while HT had little effect on nitrate reduction in both solutions. Field emission scanning electron microscopy (FESEM) analysis showed association of MT and NMH with Fe(0) surface, presumably due to magnetic attraction. The rate enhancement effect of the minerals is presumed to arise from its role as an electron mediator that facilitated electron transport from Fe(0) to nitrate. The greater enhancement of MT and NMH in groundwater was attributed to surface charge neutralization by calcium and magnesium ions in groundwater, which in turn facilitated adsorption of nitrate on Fe(0) surface.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1171-1171
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• 2001

Quantitative analysis is an important requirement in exploration, mining and processing of minerals. There is an increasing need for the use of quantitative mineralogical data to assist with bore hole logging, deposit delineation, grade control, feed to processing plants and monitoring of solid process residues. Quantitative analysis using X-Ray Powder Diffraction (XRD) requires fine grinding and the addition of a reference material, or the application of Rietveld analysis to XRD patterns to provide accurate analysis of the suite of minerals present. Whilst accurate quantitative data can be obtained in this manner, the method is time consuming and limited to the laboratory. Mid infrared when combined with multivariant analysis has also been used for quantitative analysis. However, factors such as the absorption coefficients and refractive index of the minerals requires special sample preparation and dilution in a dispersive medium, such as KBr to minimize distortion of spectral features. In contrast, the lower intensity of the overtones and combinations of the fundamental vibrations in the near infrared allow direct measurement of virtually any solid without special sample preparation or dilution. Thus Near Infrared Spectroscopy (NIR) has found application for quantitative on-line/in line analysis and control in a range of processing applications which include, moisture control in clay and textile processing, fermentation processes, wheat analysis, gasoline analysis and chemicals and polymers. It is developing rapidly in the mineral exploration industry and has been underpinned by the development of portable NIR spectrometers and spectral libraries of a wide range of minerals. For example, iron ores have been identified and characterized in terms of the individual mineral components using field spectrometers. Data acquisition time of NIR field instruments is of the order of seconds and sample preparation is minimal. Consequently these types of spectrometers have great potential for in-line or on-line application in the minerals industry. To demonstrate the applicability of NIR field spectroscopy for quantitative analysis of minerals, a specific example on the quantification of lateritic bauxites will be presented. It has been shown that the application of Partial Least Squares regression analysis (PLS) to the NIR spectra can be used to quantify chemistry and mineralogy in a range of lateritic bauxites. Important, issues such as sampling, precision, repeatability, and replication which influence the results will be discussed.

• 한국식품영양과학회지
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• 제31권4호
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• pp.658-663
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• 2002

본 연구에서는 철의 섭취수준이 증가함에 따라 다양한 무기질의 이용변화를 알아보기 위하여 흰쥐를 대상으로 적정수준, 적정수준의 2배와 4배의 철을 6주간 공급한 후 칼슘, 마그네슘, 나트륨, 칼륨, 철, 구리, 아연의 혈청 수준 및 섭취량과 배설량에 의한 평형상태를 비교, 분석하였으며, 그 결과를 요약하면 다음과 같다. 사료 섭취량, 체중 증가량 및 사료효율은 철 보충에 따른 유의한 차이가 없었다. 철 보충에 따른 혈청 철과 아연 함량은 각 군별 차이를 보여 철 함량은 2배 공급군이 유의하게 낮았고 아연 함량은 4배 공급군이 다른 두군에 비해 유의적으로 높았다(p<0.05, p<0.05). 철 보충에 따라 철 섭취량이 유의적으로 증가한 것(p<0.01)을 제외하고 그 밖의 무기질 섭취량은 유의한 차이가 없었다. 소변 중 무기질 배설량은 철 보충에 따라 칼슘, 나트륨, 철, 구리, 아연이 각 군별 유의한 차이를 보였다(p<0.01, p<0.01, p<0.001, p<0.05, p<0.01). 대변 중 무기질 배설량은 철 보충에 따른 유의한 차이가 없었다. 1일 무기질 보유량은 철 보충에 따라 나트륨과 철이 유의한 차이를 보여(p<0.05, p<0.01) 철 보충이 증가할수록 이들 무기질의 보유량이 높게 나타났다. 그러나 무기질 흡수율은 철 보충에 따라 유의한 차이가 없었다. 이상의 연구결과를 종합할 때 요구량의 2배와 4배의 철 보충에 따라 무기질의 겉보기 흡수율은 유의한 차이가 없었다. 그러나 칼슘, 철, 구리, 아연의 소변중 배설량은 철 보충에 따라 유의적으로 감소함으로써 장기적인 철 보충이 이루어진다면 이와 같은 무기질의 체내 보유량이 감소함에 따라 영양상태가 저하될 수 있을 것으로 보여진다. 이와 같은 결과는 다양한 무기질의 평형상태를 유지하기 위 해서는 무기질 보충제를 이용하는 것보다 균형 잡힌 영양섭취나 일상식사를 통해 적정한 섭취수준을 유지하는 것이 중요하다는 것을 제시해주며, 앞으로 이에 대한 영양지도와 지속적 인 연구가 요구된다.

• Nutrition Research and Practice
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• 제5권1호
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• pp.3-10
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• 2011

Women's nutrition has received little attention in nutrition programming, even though clinical trials and intervention trials have suggested that dietary improvement or supplementation with several nutrients may improve their health, especially in low-income settings, the main focus of this paper. Most attention so far has focused on how improvements in maternal nutrition can improve health outcomes for infants and young children. Adequate vitamin D and calcium nutrition throughout life may reduce the risk of osteoporosis, and calcium supplementation during pregnancy may reduce preeclampsia and low birth weight. To reduce neural tube defects, additional folic acid and possibly vitamin $B_{12}$ need to be provided to non-deficient women before they know they are pregnant. This is best achieved by fortifying a staple food. It is unclear whether maternal vitamin A supplementation will lead to improved health outcomes for mother or child. Iron, iodine and zinc supplementation are widely needed for deficient women. Multimicronutrient supplementation (MMS) in place of the more common iron-folate supplements given in pregnancy in low-income countries may slightly increase birth weight, but its impact on neonatal mortality and other outcomes is unclear. More sustainable alternative approaches deserve greater research attention.

• 대한가정학회지
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• 제41권8호
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• pp.55-62
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• 2003

Natural dyes generally fan into two categories; organic dyes coming from animals and plants and inorganic dyes obtained from various minerals such as bengala, loess, ultramarine, prussian blue and etc. The main components of volcanic ash is clay mineral such as kaolinite, illite, quartz. Clay minerals Composing volcanic ash are kaolinite［$Al_4Si_4O_{10}{(OH)_{8}}$］, illite［$K_{X}Al_2(Si,\;Al)_4O_{10}{(OH)}_2$］, quartz［$SiO_2$］, homblende［$Na_{0-1}\;Ca_2{(Mg,\;Fe,\;Al)}_5{(Si,\;Al)}_{8}O_{22}{(OH)}_2$］and etc. And the redish color mainly comes from iron oxide. In this paper, two different classes of dyeing process were tested; dyeing with volcanic ash only and cationic agent pre-treatment followed by dyeing with volcanic ash. The compositions of the volcanic ash powder and the volcanic ash deposited on the cotton knitted fabrics identified by energy dispersive spectrometer and XRD analysis. The major chemical components of volcanic ash deposited on the cotton knitted fabrics were confirmed to be the saicon oxide, iron oxide, and aluminum oxide and etc. According to the analysis by XRD and EDS-SEM, kaolinite, illite and quartz were also identified.

• Asian-Australasian Journal of Animal Sciences
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• 제12권2호
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• pp.189-191
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• 1999

Mineral profile of serum and cerebrospinal fluid (CSF) of 15 Himalayan Yak (adult female, n=8; adult male n=4 and young male,n=3) was studied in their natural habitat at an altitude of 3300 meters above mean sea level at Sangla in north western Himalayas. The macro and micro minerals estimated in serum and CSF were; Sodium, Potassium, Calcium and Magnesium and Zinc, Copper and Iron respectively. The values recorded among different Yak groups did not significantly differ from each other except serum iron and haemoglobin which were significantly higher (p<0.05 ) in young male Yaks compared to the adult male and female Yaks. An observation of great significance was considerably higher potassium and lower sodium level in Yaks compared to other bovine species of plains. The serum potassium values in some adult female Yaks were recorded as high as 10.4 mEq/l and the values varied between 6.6 to 9.8 mEq/l in young male Yaks. The serum Sodium values and Na:K ratios in Yak serum ranged between 117.5 to 122.6 mEq/l and 13.7 to 15.3 respectively. The possible relationship of high serum Potassium value with hypoxic conditions and hostile mountain environment has been discussed.

• 대한토목학회논문집
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• 제33권4호
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• pp.1463-1469
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• 2013

고화제로 사용되는 포틀랜드 시멘트와 2가철을 이용하여 염소계 유기화합물을 탈염소화 시키는 기술은 많은 연구로부터 알려져 왔다. 하지만 TCE (trichloroethylene)의 탈염소화에 관계하는 명확한 유효물질 및 기작 규명은 요원한 상태이다. 많은 연구에서 ettringite와 monosulfate와 같은 시멘트 수화물질이 TCE의 탈염소화 반응에 관여할 가능성을 보고한 바 있다. 따라서 본 연구에서는 TCE의 탈염소화 반응에 유효물질로 예상 되어왔던 ettringite와 monosulfate를 별도로 합성하여, TCE 제거 실험을 수행함으로서 기존 시멘트/2가철을 사용한 TCE 분해제거에 관계하는 명확한 유효물질 및 기작을 규명 하고자 하였다. 실험결과, $Fe^{3+}$ 및 $Al^{3+}$로 구성된 ettringite, monosulfate 합성에 성공하였고, 이후 2가철을 첨가하여 TCE 분해실험에서 합성물의 분해능을 확인하였지만 뚜렷한 제거가 나타나지 않았다. 이는 기존문헌의 예상과는 상반된 결과를 나타냈으며, 실험결과를 통해 시멘트/2가철을 사용한 TCE 제거 실험의 분해기작을 예상할 수 있었다. 예상 되는 분해기작으로는 ettringite 및 monosulfate 외의 시멘트 수화물에 의한 것과 C3A외의 시멘트 클링커 화합물 그리고 시멘트 내 trace metal에 의한 영향일 것으로 추측하였다.

• 자원환경지질
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• 제19권2호
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• pp.85-96
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• 1986

The Bupyeong Silver mine which is located approximately 35km west of Seoul is currently the leading silver producer in Korea. The deposits occur as stockwork deposits hosted in Jurassic pyroclastic rocks. Occurrences of ore deposits and mineral paragenesis suggest a division of mineralization into four stages: Stage I, deposition of iron oxide and base metal sulfides; Stage II, deposition of tin oxide and silverm inerals; stage III, deposition of native silver and other silver minerals; Stage IV, formation of pyrite bearing siderite veinlets, Silver minerals in ore are native silver, argentite, freibergite, pyrargyrite, canfieldite, polybasite, dyscrasite and Ag-Fe-S mineral. The most important silver mineral is native silver among them. Chemical composition of important silver minerals were determined by electron probe microanalyser. Assay, size and modal analyses for floatation products were carried out. In floatation products, relative proportion of native silver for total important silver minerals have following ranges: feed, 64.7 to 74.74 wt.%; A-cleaner concentrate, 80.58 to 98.79 wt.%; and final tailing, 28.12 to 72. 57 wt. %. Average degree of liberation for native silver in feed and A-cleaner concentrate are 60.49% and 77.57% respectively. Negative relationship can be recognized between native silver and argentite in their abundance and behavior in floatation precesses.