• 자원환경지질
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• 제26권1호
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• pp.41-54
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• 1993

경상분지 남동부에 위치한 울산광산은 석회암을 교대한 전형적인 calcareous skarn강상으로 Fe W광화작용 이외에도 Cu, Pb, Zn, As, Bi, Ni, Co, Cr, Ag, Sn, In, Te, Sb 등이 수반되는 다금속광화작용의 특성을 보여주고 있다. 본 광상은 직립에 가까운 파이프상 광체로 산출되며, 자철석과 함께 북측의 혼펠스와의 경계부근에 회중석이 부분적으로 광염되어 있다. 본 광상의 스카른대는 석회암 및 혼펠스를 교대한 괴상 스카른과 양자를 각기 절단하는 맥상스카른으로 구분된다. 괴상스카른은 석회암 기원의 스카른이 주체를 이루며, 이러한 스카른대는 규회석 스카른, 석류석 스카른, 단사휘석-석류석 스카른, 단사휘석 스카른으로 분류되며, 부분적으로 스카른대 주변부를 따라 거정질 방해석대가 존재하고 있다. 스카른 진화과정은 초기스카른 및 후기스카른의 두 시기로 분류되며, 초기스카른은 prograde한 스카른 생성시기로 초기에는 규회석, Mg-rich 단사휘석, Al-rich garnet가 주로 정출되며 광석광물은 거의 불모한 시기이나, 초기스카른의 말기로 진행됨에 따라 자철석과 회중석이 정출된다. 그리고, 후기스카른의 전반기까지는 Fe-rich 단사휘석, Fe-rich garnet와 함께 자철석 회중석이 연속적으로 정출되었으나, 후기스카른의 중기부터는 Ni, Co, As, Cu, Zn, Fe, Bi 등의 황화광물이 정출되는 다금속광화 작용의 특정을 보인다. 또한, 최후기 열수작용시기에는 섬아연석과 방연석 등의 Base-metal 황화광물이 주로 정출되는 연 아연 광화작용의 양상을 나타낸다. 이러한 각 광화시기별 스카른 광물과 광석광물의 변화양상은 고온의 열수용액이 천부로 유출되는 과정에서 광화용액의 온도가 급격히 떨어진 결과 (telescope)에 기인된 것으로 사료된다.

• 한국식품영양학회지
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• 제21권2호
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• pp.256-262
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• 2008

This study was carried out to compare the hair mineral status of obese, over-weighted and non-obese individuals, to gather basic data for customizing menu development and to create an education manual for the obese persons. Food preferences or various disease states could be suggested by different mineral patterns in TMA(tissue mineral analysis). The results indicated that Zn status was considerably lower in the obese individuals than in the non-obese(p<0.001) whereas hair Na(p<0.0001), K(p<0.01) and Fe(p<0.05) were at significantly higher levels in the obese individuals. The ratio of Ca/K(p<0.001) was significantly lower in the obese than in the non-obese. But the levels of hair toxic minerals such as Sb, As, Hb, Al et al. were not differ according to BMI groups. The obtained data demonstrate the changes of hair mineral content in both overweight and obese individuals thus suggesting metabolic mineral disturbance in those groups.

• Transactions on Electrical and Electronic Materials
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• 제10권5호
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• pp.152-155
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• 2009

The microstructure and the electrical properties of a ZnO varistor, which was composed of a ZnO-$Bi_2O_3$-$Sb_2O_3$-CoO- $MnO_2$ -NiO-$Nd_2O_3$ system, were investigated at various $Y_2O_3$ addition concentrations. $Y_2O_3$ played a role in the inhibition of the grain growth. As the $Y_2O_3$ content increased, the average grain size decreased from $6.8{\mu}m$ to $4{\mu}m$, and the varistor voltage($V_{1mA}$) greatly increased from 275 to 400 V/mm. The nonlinearity coefficient ($\alpha$) decreased from 72 to 65 with increasing $Y_2O_3$ amount. On the other hand, the leakage current ($I_L$) increased from 0.2 to 0.9 ${\mu}A$. These results confirmed that doping the varistors with $Y_2O_3$ is a promising production route for production of a higher fine-grained varistor voltage ($V_{1mA}$) which can dramatically reduce the size of the varistors.

• 한국환경과학회지
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• 제27권7호
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• pp.543-554
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• 2018

From November 2013 to December 2016, ambient fine particulate matter ($PM_{2.5}$) was sampled in the downtown area of Jeju City, South Korea, which has seen rapid urbanization. The atmospheric concentrations of elements were measured in the $PM_{2.5}$ samples. This study focused on Cd, Cr, Cu, Mn, Ni, Pb, As, Sb, Sn, V, and Zn. The concentrations of Al, Na, K, Fe, Ca, Mg, Sr, and La were also obtained for reference. The objectives of this study were to examine the contributions of these elements to $PM_{2.5}$ concentrations in downtown Jeju City, and to investigate the inter-element relationships and the elemental sources by using enrichment factors and principal components analysis (PCA). A composition analysis showed that the 19 elements constituted 6.65 % of the $PM_{2.5}$ mass, and Na, K, Al, Fe, Ca, Mg, and Zn constituted 98 % of the total ion mass. Seasonal trend analysis for the sampling period indicated that the concentrations of the elements increased from November to April. However, no substantial seasonal variations were found in the concentrations of the elements. The composition ratios of some elements (Cu/Zn, Cu/Cd, Cu/Pb, V/Ni, and V/La) were found to be out of range when compared to the literature from other urban areas. The ratios between the elements and the PCA results showed that local contaminant sources in Jeju City rarely influence the composition of $PM_{2.5}$. This suggests that the major sources of $PM_{2.5}$ in Jeju City may include long-range transport of fine particulate matter produced in other areas.

• Environmental Engineering Research
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• 제24권2호
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• pp.331-338
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• 2019

Particulate matter (PM) was collected using micro-orifice uniform deposit impactors from a residential (RES) site and an industrial (IND) site in Ulsan, South Korea, in September-October 2014. The PM samples were measured based on their size distributions (11 stages), ranging from $0.06{\mu}m$ to over $18.0{\mu}m$. Nine trace metals (As, Se, Cr, V, Cd, Pb, Ba, Sb, and Zn) associated with PM were analyzed. The PM samples exhibited weak bimodal distributions irrespective of sampling sites and events, and the mean concentrations of total PM (TPM) measured at the IND site ($56.7{\mu}g/m^3$) was higher than that measured at the RES site ($38.2{\mu}g/m^3$). The IND site also showed higher levels of nine trace metals, reflecting the influence of industrial activities and traffic emissions. At both sites, four trace metals (Ba, Zn, V, and Cr) contributed to over 80% of the total concentrations in TPM. The modality of individual trace metals was not strong except for Zn; however, the nine trace metals in $PM_{2.5}$ and $PM_{10}$ accounted for approximately 50% and 90% of the total concentrations in TPM, respectively. This result indicates that the size distributions of PM and trace metals are important to understand how respirable PM affects public health.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.178-178
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• 2010

칼코게나이드계 재료를 사용한 비냉각 적외선 센서의 윈도우를 제작하여 그 특성을 조사하였다. 조성을 EDS로 분석한 결과 Ge-Se-Sb로 구성되어 있음을 확인하였다. 두께 2mm인 윈도우 모재를 양면 경연마한 후 코팅 설계치로 8-12um 영역에서 평균 투과도가 95.6%로 나타났다. 이온빔보조증착장치를 이용하여 Ge, ZnS, $YF_3$ 소스로 코팅한 결과 투과도는 동일파장영역에서 약 94%로 나타났다. 칼코게나이드 원재료의 투과도는 약 69%로써 12um 영역 부근에서 강한흡수를 보였다. 코팅면의 거칠기 값(Ra)은 약 1.5 nm로써 매우 매끄러운 면을 얻었으며, 단면 SEM 측정 결과 설계치와 유사한 박막 두께를 얻었다.

• 한국자원식물학회지
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• 제3권2호
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• pp.107-114
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• 1990

In view of the results to have measured metallic elements which is included in 45 sorts of herb medicines and surveyed their distribution, 8 kinds ofmetals including Co, Ge, Ga, TL, Cd, As, 8i, Pb, are never or little includedin almost herb medicines . Other twenty-five sorts of elements (Mo, Sc, Be, V,Ni, Sn, Se, Ba, Cr, Sb, Si, Ti, B, Li, Mg, Ca, Cr, Mn, Fe, Cu, Zn, p, Al, Na,K) are more or Less included in all herb Bedicines ana Na, Ca, p and K aremetals that are included in Large quentities in comrarison with others . Patri-uiae Radix Contains 7 kinds of metal lic elements more than other herb medicinesdoes .

• 한국자원식물학회지
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• 제4권2호
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• pp.39-45
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• 1991

Proximate compositions of the roots of cultured and wild Codonopsis lanceolata were examined as tile basic reasearch for the study of their source of processed foods.No significant difference in the contents was found between the wild root and thecultivated at 3$0^{\circ}C$ in biotronroom. In view of the results to have measured mineralswhich is included in 14 sorts of Codonopsis lanceolata and surveyed their distribution.12 kinds of minerals including T1, Co, Ge, Sm, Mo, Sc, Be, Cd, As, Ga, Bi, ph are ne-vel or little included in almost source. Other twenty-one sorts of minerals (Ni, Se,Ba, Sb, Si, Ti, B, Li, Ifs, Ca, Sr, Mn, Fe, Cu, Zn, p, Al, Na, V, Cr, K) are more or less in-cluded in all source and Ca, Mg, p, K, and Fe are metals that are included in large qu-entities in comparison with others. No minerals difference in the contents was foundbetween the cultivated temperature. The content of elements of inorganic metal differsaccording to the part of C. lanceolata.

• 한국세라믹학회지
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• 제12권1호
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• pp.5-11
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• 1975

Thick film resistor paste was made utilizing oxide materials such as SnO, SnO＋Sb2O3, and SnO＋Zn. The oxide materials were mixed respectively with Q-12 glass powder and finally suspended in ethyl cellulose dissolved in ethyl cellosolve. Thick film resistor was made by screen printing the paste on the alumina substrate and firing it at a suitable temperature. Among thick films made from the resistor paste, the thick film containing 85% SnO and fired at $600^{\circ}C$ demonstrated the finest electrical properties showing 10 K ohm in sheet resistance, 110 ppm/$^{\circ}C$ in TCR. In general, TCR of the thick films made from the oxide-mixture paste is good in linearity, therefore it is suggested the oxide-mixture paste is utilized as the negative thermistor.

• 자원환경지질
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• 제40권6호
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• pp.713-726
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• 2007

대봉광상은 선캠브리아기 경기육괴의 호상편마암 또는 화강편마암내에 발달된 단층($N10{\sim}20^{\circ}W,\;40{\sim}60^{\circ}SW$)을 따라 충진한 중열수 함금-은 괴상 석영맥광상이다. 이 광상의 광화작용은 여러번의 단열작용에 의해 형성된 괴상 백색 석영맥(광화I시기)과 투명 석영맥(광화II시기)으로 구성된다. 광화I시기의 열수작용에 의한 변질작용은 견운모화, 녹니석화, 탄산염화, 황철석화, 규화 및 점토화작용 등이 관찰되며, 견운모대는 석영맥과 접촉한 부분에서, 녹니석대는 석영맥으로부터 멀어짐에 따라 관찰된다. 견운모대의 모암변질광물은 대부분이 견운모 및 석영이며, 일부 일라이트, 탄산염광물, 녹염석으로 구성된다. 녹니석대의 모암변질광물은 주로 녹니석, 석영과 소량 견운모, 탄산염광물 및 녹염석으로 구성된다. 견운모의 Fe/(Fe+Mg) 값은 $0.36{\sim}0.59(0.51{\pm}0.10)$이며, 백운모-페차이트족에 해당되고 녹니석의 Fe/(Fe+Mg) 값은 $0.66{\sim}0.73(0.70{\pm}0.02)$이고 대부분 브룬스비자이트에 해당된다. 견운모와 녹니석에 대한 $Al_{IV}-Fe/(Fe+Mg)$의 다이어그램은 변질 시 같은 광종의 견운모와 녹니석의 형성온도를 나타내는 지시자로서 유용하다. 이것은 계산된 녹니석 단종의 활동도가 $a3(Fe_5Al_2Si_3O_{10}(OH){_6}:0.00964{\sim}0.0291,\;a2(Mg_5Al_2Si_3O_{10}(OH){_6}:9.99E-07{\sim}1.87E-05,\;a1(Mg_6Si_4O_{10}(OH){_6}:5.61E-07{\sim}1.79E-05$로서 대봉광상의 녹니석은 철이 풍부한 녹니석으로 비교적 고온($T>450^{\circ}C$)에서 모암과 평형상태에서 온도가 감소함에 따라 형성되었음을 알 수 있다. 모암변질시 $log\;{\alpha}K^+/{\alpha}H^+,\;log\;{\alpha}Na^+/{\alpha}H^+,\;log\;{\alpha}Ca^{2+}/{\alpha}^2H^+$ 값은 각각 $4.6(400^{\circ}C),\;4.1(350^{\circ}C),\;4.0(400^{\circ}C),\;4.2(350^{\circ}C),\;1.8(400^{\circ}C),\;4.5(350^{\circ}C)$이고 pH는 각각 $5.4{\sim}6.5(400^{\circ}C),\;5.1{\sim}5.5(350^{\circ}C)$로서 모암변질시 열수용액은 약산성이었음을 알 수 있다. 모암변질시 이득원소(부화원소)는 $K_2O,\;P_2O_5,\;Na2O$, Ba, Sr Cr, Sc, V, Pb, Zn, Be, Ag, As, Ta, Sb이며 특히 Sr, V, Pb, Zn, As, Sb등의 원소는 현저하게 증가하므로 중열수 및 천열수 금-은광상의 탐사에 지시원소로서 활용될 수 있을 것이다.