• 자원리싸이클링
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• 제32권6호
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• pp.54-66
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• 2023

타이타늄은 다양한 용도에 사용되고 있어 광물자원으로서의 중요성이 높아지고 있으나 대부분 수입에 의존하고 있다. 국내에도 주로 일메나이트로 구성된 타이타늄 원광이 존재하며 이를 개발하기 위한 연구가 진행되고 있지만 원료 소재로의 개발은 진행되고 있지 않아 안정적인 타이타늄 공급망을 확보하기 위한 대책이 시급하다. 이에 본 연구에서는 타이타늄 광물의 안정적인 확보를 위해 선광 기술별 기초 실험을 실시하여 유가광물의 효율적 회수를 위한 기술 적용 가능성을 평가하였다. 실험 결과, 풍화작용으로 인한 광물들의 입자가 미립의 형태로 존재하여 분급을 통한 회수는 어려운 것으로 확인되었다. 비중선별, 부유선별 및 자력선별의 선광기술을 적용한 결과, 적철석과 금홍석 등의 유가광물 회수가 가능하다. 그러나 타이타늄 광석에 함유된 적철석과 금홍석이 미세한 입자로 물리적으로 결합되어 있는 광물학적 특성에 의해 산화티탄의 품위와 실수율을 높이는데 한계성이 있다. 따라서 타이타늄 광석 내 산화티탄과 더불어 철, 바나듐, 희토류 성분도 함께 자원으로 활용할 수 있는 용도 개발이 필요하며, 이를 위해서 구성광물 간 단체분리도 향상 분쇄 기술, 미세한 광물입자 간 자력 감응 차이를 이용한 자력선별 기술, 그리고 산화철 및 산화티탄 성분의 개질 후 유가물질을 경제적으로 확보할 수 있는 선광 기술의 개발이 필요하다.

• 아시안잔디학회지
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• 제10권2호
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• pp.105-115
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• 1996

To find out the mineral cycles of calcium, magnesium and sodium in dynamic grassland cosystems in a steady state condition, this investigation was conducted along the northwest side on Mt. Kwanak. The experimental results may he suromarized on the communities of a Zoysia japonica and a Miscanthus sinesis as follows. As compared with some properties of the surface soils among two semi-natural grasslands, cal- cium (Ca) was greater quantity in a Zoysia japonica, whereas, in a Miscanthus sicensis, sodium (Na)and magnesium (Mg) were greater in Mt. Kwanak. For the case of steady production and release, the ratio of annual mineral production to the amount accumulated on the top of mineral soil in a steady state provides the estimates of release constant k. The release constants of Ca, Mg and Na of the litter were 0.42, 0.25 and 0.29 in the Zoysia japonica grassland, and were 0.41, 0.54 arid 0.62 in the Miscanthus sinensis grassland, respect- ively. The half times of Ca, Mg and Na required for the release or accumulation of the litter on the grassland were 1.65, 2.77 and 2.39 in the Zoysia japonica, and were 1.69, 1.28 and 1.12 in the Miscauthus sinensis, respectively. The increasing order of the turnover parameters of the elements was Ca, Na and Mg in the Zoysia japonica grassland, and was Na, Mg and Ca in the Miscanthus Si nens is grassland. The amounts of annual cycles for Ca, Mg, Na in the grassland ecosystem under the steady-state conditions were 1.29, 0.20 and 0.12 g /m$^2$ in the Zoysia japonica grassland and 3.91, 1.04 and 0.61 g /m$^2$ in the Miscanthus sinensis grassland.

• Journal of Periodontal and Implant Science
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• 제44권5호
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• pp.227-234
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• 2014

Purpose: Dentin hypersensitivity is a potential threat to oral health. Laser irradiation may provide reliable and reproducible treatment but remains controversial. The present study aimed to evaluate the effects of $CO_2$ or erbium-doped yttrium aluminium garnet (Er:YAG) laser therapy, and to assess mineral content. Methods: Eighteen human single-rooted teeth affected with advanced periodontitis were obtained. Buccal and lingual surfaces were planed to form 36 specimens. Ethylenediaminetetraacetic acid gel (24%) was applied to remove the smear layer and simulate hypersensitive teeth. The experimental groups were: group 1, control (no irradiation); group 2, $CO_2$ laser (repetitive pulsed mode, 2 W, $2.7J/cm^2$); and group 3, Er:YAG laser (slight contact mode, 40 mJ/pulse and 10 Hz). To evaluate dentinal tubule occlusion, six specimens per group (2-mm thickness) were prepared and observed using scanning electron microscopy (SEM) for calculation of the occlusion percentage. To evaluate the mineral content, six specimens per group (0.6-mm thickness) were used, and then the levels of Ca, K, Mg, Na, and P were measured by inductively coupled plasma-atomic emission spectrometry. In addition, the surface temperature of the specimens during laser irradiation was analyzed by a thermograph. Results: The SEM photomicrographs indicated melted areas around exposed dentinal tubules and a significantly greater percentage of tubular occlusion in the $CO_2$ and Er:YAG laser groups than the control, and in the Er:YAG group than the $CO_2$ laser group. In addition, no significant differences were noted among the experimental groups for the mineral elements analyzed. The $CO_2$ laser group showed an evident thermal effect compared to the Er:YAG group. Conclusions: $CO_2$ and Er:YAG laser are effective in treating dentin hypersensitivity and reducing its symptoms. However, the Er:YAG laser has a more significant effect; thus, it may constitute a useful conditioning item. Furthermore, neither $CO_2$ nor Er:YAG lasers affected the compositional structure of the mineral content.

• Preventive Nutrition and Food Science
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• 제9권4호
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• pp.374-382
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• 2004

The concern of the antioxidant micronutrient status in normal healthy people, including antioxidant trace minerals such as Cu, Zn, Mn, Fe and Se is focused since systemic oxidation is involved in various chronic diseases. In the present study, we evaluated the concentration of trace minerals (Cu, Zn, Mn, and Fe) which are considered as potential antioxidant minerals in plasma, red blood cells (RBCs) and urine in normal healthy Korean subjects. The 760 subjects (male 341, female 419; mean age 54.2 $\pm$ 18.9) were recruited from the rural, urban and metropolitan city in South Korea. Dietary intake was evaluated using 24-hours recall for general major nutrient intake assessment. The trace elements (Cu, Zn, Mn, and Fe) concentrations in plasma, RBCs, and urine were measured by inductively coupled plasma spectrophotometer (ICP) and atomic absorption spectrophotometer (AAS). Cu and Zn levels in plasma, RBCs and urine in normal healthy South Koreans were within the normal range of those mineral levels, but Mn and Fe levels were higher compared to the normal range of those mineral levels. None of the selected trace mineral levels in plasma and RBC's was lower than the normal range value. The results showed that Zn and Cu levels in plasma and RBC's in Korean were within the normal range, and plasma and urinary Mn and Fe levels were higher than the normal reference values. Potential antioxidant trace mineral (Cu, Mn, Zn and Fe) levels in Koreans are within or a bit higher than the normal range.

• 분석과학
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• 제17권4호
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• pp.308-314
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• 2004

전자소재의 원료물질 혹은 보호물질에 사용되는 고분자수지내에 포함된 U, Th과 이들의 붕괴산물인 딸핵종과 같은 방사성 불순물이 있는 경우 전자소자의 오작동을 일으키는 주 요인으로 알려져 있으며, Na, Cl, Fe 등과 같은 이온성 불순물은 소자의 수명을 단축시키는 것으로 알려져 있어 극미량 무기불순물의 정확한 분석이 필요하다. NAA의 경우, 위와 같은 분석의 문제점인 시료전처리가 필요하지 않은 비파괴 분석이 가능하여 가장 적합한 분석법으로서 고분자수지중의 극미량 불순물 분석을 위한 시료 전처리법과 최적 분석방법을 개발하였다. 이 방법을 사용하여 전자소재의 밀봉보호재로 널리 이용되고 있는 에폭시수지와 페놀수지중의 극미량 무기 불순물을 분석기술을 개발하였으며, 그 결과 U, Th과 이온성 불순물인 Cl, Fe, Na 외에 20가지의 미량 무기불순물을 분석할 수 있었다.

• 자원환경지질
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• 제21권4호
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• pp.389-400
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• 1988

Minor elements such as Ag, As, Au, Bi, Cd, Cu, Co, Ni, Pb, Rb, Sb, Sr and Te were analyzed by atomic absorption spectrophotometry and induced coupled plasma spectrophotometry in order to investigate pathfinders for gold in quartz porphyry, granite porphyry and vein materials in Jeonjuil gold - silver mine, and in altered biotite granites and vein materials in Dukum gold - silver mine. In Dukum gold - silver mine, it is observed that Au contents have positive relation with As, Co, and Rb contents, but negative relation with Bi contents in altered biotite granites. Au contents have positive relation with Ag, As, Co and Te contents in vein materials. In Jeonjuil gold - silver mine, it is observed that Cd, Rb, Sr and Te are enriched near ore vein in quartz porphyry and granite porphyry. Au contents have positive relation with As, Cd, Cu, $Fe_2O_3$ and $K_2O$ in vein materials.

• 동의생리병리학회지
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• 제18권4호
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• pp.1159-1162
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• 2004

We studied on the production of the ceramic by the mineral-Oriental medicine and the property of the clean active water depositting on the ceramic stone. The results are as follows: We properly mixed of maifanshi, mica, ochre, and added to a small amount cinnabar, and therefore formed the ceramic stone. By the plasticity process and the irradiating magnetic force recovered the disappeared a part of constitutent elements. The recovered effects were become higher the freshness, maintenance, deodoriztion, clean water. As well as having the ability on capture of the notoxious heavy metal on human. The ceramic powder were mixed proper dose maifanshi, mica. And the powder had ionization, absorption, adhesion by the plasticity process and magnetic force. The clean active water of depositting on the ceramic stone during 24hours were observed significant the content of micro element, dissolved oxygen, abstraction on Herbs.

• Asian-Australasian Journal of Animal Sciences
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• 제20권6호
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• pp.908-913
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• 2007

Concentrations of major elements in forages were determined in relation to ruminant requirements at a livestock experimental station in Leiah district, Punjab-Pakistan using mapping techniques. The study investigated the influence of sampling periods and pasture types on the concentrations of calcium, magnesium, potassium, and sodium in forages. The implications of these forages for nutrition of ruminants were assessed for the livestock population at that particular experimental station, which are supported by the farm pastures. Within the farm, variations in the element status of the forages were related to soil pasture types. A tentative assessment of the mineral status of available forages at this farm for different pastures using guidelines developed for domestic animals indicated deficiencies of only Na, but forages contained adequate Ca, Mg, and K levels required for grazing ruminants. The concentrations of Na in the forage reserves indicated that the potential supply of this element to plants was limited from the soil to plants and from plants to the animals grazing them. Soil minerals were not measured in this study. The potential use of fertilizers, as pasture amendment as well as supplementation of ruminants, with a specifically tailored mineral mixture is important to livestock producers and environmentalists as well, because their use may improve forage nutritive value and in turn meet requirements of animals.

• 한국의류학회지
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• 제38권5호
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• pp.665-674
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• 2014

An analysis of the components of clay mineral before and after coloration (XRF) showed that the elements involved in coloration are Fe, Cr, and Ni. Fe accounts for 65% of coloring components on dyed fabric; in addition, Cr and Ni also affect coloring. The optimal coloration condition was to repeat the process of immersing the cotton fabric in $80^{\circ}C$ slurry of 8g of clay mineral to 1g cotton for 60 minutes, dry it for 24 hours and rinse three times. Especially, as the repetition of coloration increased, the $(K/S)_{440}$ value of sample A increased from 1.0 to 2.5, and sample B increased from 1.0 to 1.6. The effect of the repeated process on coloration was significant; consequently, the rinsing and drying process were important to decrease the coloration level. It also showed excellent results in regard to color fastness to washing, light, rubbing, perspiration, and antibiotic effect.

• 대한예방한의학회지
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• 제5권1호
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• pp.31-40
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• 2001

Legal permissible limit of herbal drugs metal level in Korea is define 'less 30.0ppm in total(except mineral drugs)' including Pb Hg Cd As Cr Ni etc. This limit has a lot of problems in several factors, that is, not divide hazard and essential elements, not consider high and low toxic effect in each metal, not calculate dose-response relationship and average health behavior in Korean etc. As a that result, It has strong limits and weakness in the basic toxicology and Oriental medicine. To improve and correct these factors, We need to several new approach as like below. It must be radical study following problems in short and middle-long period in the future, toxic metal and essential element must be divide to basic toxicology and also be diverse toxic effect. But mineral drugs that included a amount of severe toxic metals is being used as active prescription drug until now. If toxic, safety and side-effect of metals will be considered, mineral drugs must prohibit instantly or use at least after examined toxic effect. But one of the most important things about herbal drugs contamination, all people and department (government, farmer and trader, oriental medicine doctors and association) will be participate cooperative and collection for preventive or the least contamination in herbal drugs.