• 한국산학기술학회논문지
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• 제4권3호
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• pp.307-311
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• 2003

탈염기 혼합 이온교환 수지탑에서 양 ㆍ 음이온의 최적혼합비율을 결정하기 위해 실험을 수행하였다. 2, 3, 4, 5 성분 양ㆍ음이온 흡착은 많은 양이온 그리고 음이온의 선택도를 얻기 위하여 small-volume batch test로부터 실험 데이터를 얻기 위해 수행되었다. Quantitative run time은 반-실험적 질량 작용과 표면 착화 모델을 이용한 이온 교환 모델에 의해서 추정될 수 있었다. 탈염기 수지층의 음이온 교환수지에 대한 양이온 교환수지의 비율을 증가시킴으로써 더 길게 사용될 수 있다.

• 한국환경과학회지
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• 제15권11호
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• pp.1027-1034
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• 2006

Antimicrobial powder was made by exchanging silver ion on calcined oyster shell. On the purpose of application to water clarifier, bail-type media mixed with antimicrobial powder and $0{\sim}30%$ white kaoline were made. The sterilization effect, pore size distribution and zeta potential was tested to indicate the condition for the media of water clarifier. From these tests, it was confirmed that this media have an excellent sterilization power on $G^-\;and\;G^+$ germs. As the concentration of the exchanged silver ion increased, the surface charge density of the anions on the surface of the media also increased. The surface pore size decreased with the concentration of silver ion and 20% more white kaoline ratio. Consequently, mixing ratio of white kaoline would appear to indicate the optimun condition as media have sterilization power.

• 방사성폐기물학회지
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• 제4권4호
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• pp.373-384
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• 2006

중수로 원전내 여러 계통으로 부터 발생된 폐수지내에는 $^{14}C$ 핵종이 다량 함유되어 있으며, Class A 및 C 폐기물로 분류되는 폐수지의 적정 처리 기술 개발을 위한 기초연구를 수행하였다. IRN-150 혼상 이온교환수지를 이용하여 비방사성 $HCO_3$ 이온과 양이온의 흡착 특성 및 탈차용액을 이용한 $HCO_3$ 이온의 제거 특성을 고찰하였다. IRN-150 수지의 $HCO_3$ 이온의 흡착능은 이론값에 근접한 11 mg-C/g-IRN-150을 나타내었고, $CS^+,\;CO_2^+,\;Na^+,\;NH_4^+$ 양이온의 흡착 친화도를 단일성분 및 복합성분 시스템을 이용하여 분석하였다. 여러 가지 탈착용액을 이용한 폐수지로부터 $HCO_3$ 이온의 제거 특성을 평가한 결과, $^{14}C$ 핵종을 전량 효과적으로 제거하기 위해서는 $NaNO_3,\;Na_3PO_3$ 보다도 $NH_4H_2PO_4$ 용액이 유리한 것으로 나타났다.

• Nuclear Engineering and Technology
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• 제46권6호
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• pp.847-856
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• 2014

Spent resin waste containing a high concentration of $^{14}C$ radionuclide cannot be disposed of directly. A fundamental study on selective $^{14}C$ stripping, especially from the IRN-150 mixed bed resin, was carried out. In single ion-exchange equilibrium isotherm experiments, the ion adsorption capacity of the fresh resin for non-radioactive $HCO_3{^-}$ ion, as the chemical form of $^{14}C$, was evaluated as 11mg-C/g-resin. Adsorption affinity of anions to the resin was derived in order of $NO_3{^-}$ > $HCO_3{^-}{\geq}H_2PO_4{^-}$. Thus the competitive adsorption affinity of $NO_3{^-}$ ion in binary systems appeared far higher than that of $HCO_3{^-}$ or $H_2PO_4{^-}$, and the selective desorption of $HCO_3{^-}$ from the resin was very effective. On one hand, the affinity of $Co^{2+}$ and $Cs^+$ for the resin remained relatively higher than that of other cations in the same stripping solution. Desorption of $Cs^+$ was minimized when the summation of the metal ions in the spent resin and the other cations in solution was near saturation and the pH value was maintained above 4.5. Among the various solutions tested, from the view-point of the simple second waste process, $NH_4H_2PO_4$ solution was preferable for the stripping of $^{14}C$ from the spent resin.

• 대한화학회지
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• 제38권1호
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• pp.13-20
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• 1994

Anthraquinone 치환체인 1,4-DHAQ, 1,5-DHAQ, 1,8-DHAQ 및 1,8-DCAQ등을 2-propanol(PrOH)과 triethylamine(TEA)의 혼합용매에 녹여 레이저 광환원 반응에 의하여 생성되는 세미퀴논의 음이온 라디칼을 ESR분광기로 측정하였다. 또한 이들 치환체 라디칼의 초미세 구조선으로보터 초미세 분리상수를 얻어, 그 값을 이용한 컴퓨터 모의실험에 의하여 초미세분리상수(hfsc)를 결정하였다. 뿐만 아니라 측정된 ESR스펙트럼의 초미세 분리상수를 지정하기 위하여 EHMO법으로 $\pi$스핀밀도를 계산하였다.

• 대한한의학방제학회지
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• 제22권2호
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• pp.87-103
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• 2014

Objectives : Herbal formulas are complicated to analyze and difficult to compose because of its mixed, complex features. So we discussed about how to compose herbal formulas effective and efficient by analyzing various effectiveness of each herbal extracts. Methods : To evaluate the effectiveness of herbal formula, anti-oxidative and anti-inflammatory effectiveness were mathematically analyzed. DPPH, superoxide anions, Nitric Oxide scavenging activity was measured to evaluate the effectiveness of 7 herbal extracts. And next, cytotoxic activity of extracts on RAW 264.7 cells were measured using MTS assay. To asses anti-inflammatory effect, nitric oxide and $PGE_2$ production were measured. Based on these anti-oxidative and anti-inflammatory experiment result, mathematical analyzation were carried out with constOptm function, and determined efficacy-maximizing ratio. Results : This mathematical analysis based formula showed significantly outstanding effectiveness than other formulae. And estimated tendency of anti-inflammatory effectiveness was matched with real effectiveness. Conclusions : So, mathematical analysis can be available to evaluate and estimate the effectiveness of herbal formulae.

• The Korean Journal of Ceramics
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• 제5권2호
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• pp.142-147
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• 1999

The interaction between commercial $Si_3N_4$ powder and two types of additives (nitrate and oxide additives) during the sintering of $Si_3N_4$ was investigated. The nitrates solution or oxide particles were added as a sintering additives. The surface of mixed powder was observed with FT-IR, TG, and HREM. DTA was used to characterize the reactivity of the powders. The formation of crystalline phases and phase transformation were analyzed by XRD. The adsorption of the additives on the surface of silicon nitride was confirmed in the nitrate salts. It was shown that the adsorption occurred by interaction between the amorphous $SiO_2$ layer on the $Si_3N_4$ surface and metal cations $(Al^{3++\; and \;Y^{3+})$ and anions $(NO_3\;^-\; or\; OH^-)$, resulting in a higher degree of homogeneous distribution of additives.

• 한국재료학회지
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• 제22권12호
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• pp.643-649
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• 2012

Coatings composited with alumina and Perfluoro alkoxyalkane (PFA) resin were deposited on stainless steel plate (SUS304) to further improve corrosion resistance. Plate (ca. $10{\mu}m$) and/or nanosize (27~43 nm) alumina used as inorganic additives were mixed in PFA resin to make alumina-fluoro composite coatings. These coatings were deposited on SUS304 plate with wet spray coating and then the film was cured thermally. According to the amount and ratio of the two kinds of alumina having plate morphology and nano size, corrosion resistance of the film was evaluated under strong acids (HF, HCl) and a strong base (NaOH). The film prepared with the addition of 5~10 wt% alumina powders in PFA resin showed corrosion resistance superior to that of pure PFA resin film. However, for the film prepared with alumina content above 10 wt%, the corrosion resistance did not improve with the physical properties, such as surface hardness and adhesion. The film prepared with plate/nanosize (weight ratio = 1/2) alumina especially enhanced the surface hardness and corrosion resistance. This can be explained as showing that the plate and the nanosize alumina dispersed in PFA resin effectively suppressed the penetration of cations and anions due to the long penetration length and fewer defects that accompany the improved surface hardness under a serious environment of 10% HF solution for over 120 hrs.

• 한국대기환경학회지
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• 제27권5호
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• pp.523-533
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• 2011

This study had the aim of characteristics of $PM_{10}$ in subway cabins. $PM_{10}$ was measured by times of day (rush and non rush hours) and seasons with real time $PM_{10}$ sampler on the subway cabins of line 7. Filter samples were collected for evaluation of their elemental composition as well as identification of major sources of $PM_{10}$ using a receptor model, PMF. $PM_{10}$ concentration were the highest in the winter season both in the rush and non rush hours at 152.8 ${\mu}g/m^3$, 90.2 ${\mu}g/m^3$ respectively. The $PM_{10}$ concentrations in rush hour were 30% higher compared to non rush hours. Based on the chemical information, the composition rare of inorganic elements was 52.5%, anions were 10.2% and others were 37.3%. Fe was the most abundant element and significantly correlated (p.0.01) with Mn (r=0.97), Ti (r=0.91), Cr (r=0.88), Ni (r=0.89) and Cu (r=0.88). Characterized $PM_{10}$ sources by PMF in the cabin were soil and road dust related sources (27.2%), railroad related sources (47.5%), secondary nitrate sources (16.2%) and a Cl-factor mixed with a secondary sulfate source (9.1%).

• 한국토양비료학회지
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• 제15권3호
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• pp.178-187
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• 1982

초지개발이 유망시되는 전국각지의 미개간(未開墾) 산지토양(山地土壤)의 표토(表土)를 채취(採取)하여 다량(多量) 요소(要素)의 음(陰)이온총량(総量) : 양(陽)이온총량(総量)(${\Sigma}$ Anion: ${\Sigma}$ Cation) 적정시비비율(適正施肥比率)과 적정총시비량(適正総施肥量)(${\Sigma}$ion)결정(決定)을 위한 Pot시험(試驗)을 수원(水原)에서 수행(遂行)한 결과(結果)는, 1. 제주등 5개지역(個地域)의 토양(土壤)에 대한 혼파목초재배시(混播牧草栽培市) 각토양(各土壤) 및 초종별(草種別) 다수획(多收獲)을 얻기 위한 당량비기준의 음(陰)과 양(陽)이온 총량간(総量間)의 적정(適正) 시비비율(施肥比率)과 적정총시비량(適正総施肥量)이 계산(計算)되었다(표(表)6,7) 2. 혼파재배(混播栽培)에서 화본과목초(禾本科牧草)는 음(陰)이온총량(総量), 두과목초(荳科牧草)는 양(陽)이온총량(総量) 비율(比率)이 높을수록 이들의 수량(收量)과 식생구성비율(植生構成比率)이 증가(增加)하였다. 적정(適正) 음(陰)과 양(陽)이온총량(総量) 비율(比率)은 화본과목초(禾本科牧草)에서는 음(陰)이온총량(総量)이 두과목초(荳科牧草)에서는 양(陽)이온총량비율(総量比率)이 각각(各各) 타(他)이온총량비율(総量比率)보다 훨씬 높을 때였다. 3. 두과목초(荳科牧草)의 수량제고(收量提高)를 위(爲)한 적정총시비량(適正総施肥量)은 음(陰)과 양(陽)이온총량비율(総量比率)에 따라 달렀다. 양(陽)이온총량비율(総量比率)이 높아질수록 적정총(適正総)이온농도(濃度)(총시비량(総施肥量))는 증가(增加)하였고 이의 역(逆)도 성립(成立)하였다. 4. 화본과목초(禾本科牧草) 및 총수량(総收量)(화본과(禾本科)+두과(荳科))에 미치는 음(陰)과 양(陽)이온총량(総量)의 각(各) 효율(效率)은 이들의 비율(比率)이 낮을때 그리고 총(総)이온농도(濃度)가 낮을때 제일(第一) 높았다. 5. 두과목초수량(荳科牧草收量)에 미치는 음(陰)이온총량효율은 대구토양(大邱土壤)을 제외(除外)하고는 화본과목초(禾本科牧草)와 같은 경향(傾向)이였고, 양(陽)이온총량효율은 총(総)이온농도(濃度)와 토양종류(土壤種類)에 따라 달랐으나 보편적(普遍的)으로 양(陽)이온총량비율(総量比率)이 높아질수록 본효율도 높아졌다. 6. 각(各) 구성초종(構成草種)의 수량(收量), 식생비율(植生比率)은 음(陰)과 양(陽)이온총량비율(総量比率), 총(総)이온농도(濃度)와 이들의 상호작용(相互作用)에 크게 영향(影響)을 받았고, 화본과(禾本科)와 두과목초(荳科牧草)는 서로 상반적영향(相反的影響)을 받았다.