• 한국대기환경학회지
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• 제27권6호
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• pp.723-733
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• 2011

The ionic compositions were analyzed from the TSP samples collected at Gosan site in Jeju Island between 2000 and 2008, in order to examine the characteristics of atmospheric aerosols in accordance with the meteorological conditions. For the Asian Dust influence on the ionic compositions, the concentration ratios of $NH_4{^+}$, nss-${SO_4}^{2-}$, $NO_3{^-}$, and $K^+$ were about 1.2~2.3 during Asian Dust over Non-Asian Dust periods, noticeably that of nss-$Ca^{2+}$ was 6.8. Meanwhile the concentrations of nss-${SO_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$ have increased as 1.8~4.4 times during the haze event periods, and 1.0~1.6 times during the fog and mist events. The ion balance has resulted that the anionic concentrations are relatively lower than the cationic concentrations, and the discrepancy appears more decidedly as a strong Asian Dust effect. The ammonium ion balance has shown that it exists as a mixture of $NH_4HSO_4$ and $(NH_4)_2SO_4$. The concentration ratios of nss-${SO_4}^{2-}/NO_3{^-}$ for Asian Dust, haze, fog-mist, and non-event periods were respectively 1.8, 5.9, 4.6, and 2.9, which were higher values compared to those in urban areas of China as well as other domestic regions. Especially, the high ratios of sulfur oxides could be presumed by the fact that the longrange transport of air pollutants from Asia continent might affect the atmospheric aerosols of Jeju Island.

• 생물환경조절학회지
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• 제14권3호
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• pp.196-202
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• 2005

본 연구는 상토의 보수성 증가를 위하여 혼합되는 acrylamide 계통 고흡수성 수지인 Stocksorb C(STSB)의 수분 흡수 특성, 수분 흡수에 영향을 미치는 각종 무기염의 종류 및 농도, STSB가 침지된 외부용액속의 무기염 농도 변화를 구명하고자 수행하였다. STSB의 수분 흡수량은 증류수에 침지한 경우 약 180 $mL{\cdot}g^{-1}$였다. 1가의 양이온을 포함한 염인 $KH_2PO_4,\;KNO_3$ 또는 $(NH_4)_2SO_4$를 용해시킨 용액의 농도가 높아질수록 흡수량이 저하되었으나 세 종류 양이온의 종류에 따른 차이는 크지 않았다. $Ca(NO_3)_2{\cdot}4H_2O$ 다양한 농도로 용해시킨 용액 속에 STSB를 침지시킨 경우 수분흡수능 저하가 심하여 20 $meq{\cdot}L^{-1}Ca(NO_3)_2{\cdot}4H_2O$ 용액에서 약 25 $mL{\cdot}g^{-1}$ 수분을 흡수하였다. $Mg(NO_3)_2{\cdot}6H_2O$나 $MgSO_4{\cdot}7H_2O$를 용해시킨 용액의 농도가 높아질수록 수분 흡수량이 심하게 저하하였고, 1가의 양이온이 포함된 염을 용해시킨 용액에서보다 그 정도가 심하였다. 그러나 요소의 농도를 증가시킨 용액에서의 수분 흡수량은 저하되지 않았다. 침지전 Hoagland용액의 농도가 높거나, 침지시간이 길어질수록 STSB를 침지시킨 용액에서의 $K^+$및 $NH_4^+-N$의 농도가 점차 높아졌다. Hoagland 용액의 희석배수와 무관하게 침지시간이 길어질수록 외부용액의 $NO_3^--N,\;H_2PO_4^-$ 및 $SO_4^{-2}$ 농도가 약간 상승하였고, 24시간 경과 후 각각 5,300, 250 및 1,500 $mg{\cdot}L^{-1}$ 농도로 분석되었다.

• 분석과학
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• 제17권5호
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• pp.369-374
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• 2004

플라스틱을 황산으로 탄화시키고 질산으로 산화 분해한 후 과잉의 황산과 질산을 증발 건조에 의해 제거한다. 이때 침전된 납화합물 ($PbSO_4$)의 $SO{_4}^{-2}$ 이온을 염산산성에서 HI에 의해 $H_2S$로 환원하여 휘발시킨 다음 납을 용해한후 AAS와 ICP로 측정하였다. PVC-Pb 표준시료 (690~34610mg/kg)를 이용하여 재현성 실험을 하였으며 예상농도에 대비하여 99.9% 이상의 정확성을 보였다. 정밀성은 AAS는 99.8%, ICP는 99.9%로 비슷하였다.

• 한국환경농학회지
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• 제6권2호
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• pp.73-76
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• 1987

들깨 수원(水原) 8호(號)(Perilla frutescens Suwon No. 8)에 $SO_2$를 접촉(接觸)시켰을 때 일어나는 광합성색소(光合成色素)의 변화(變化)에 대(對)한 $SO_2$농도(濃度), 접촉시간(接觸時間), 광,(光) 활성산소(活性酸素)와 무기(無機) $SO_3\;^{-2}$의 영향(影響)을 관찰분석(觀察分析)한 결과(結果)는 다음과 같다. 1. $SO_2$농도(濃度)가 높아지고 접촉시간(接觸時間)이 길어질수록 피해(被害)가 심해저 엽록소(葉綠素)의 파괴(破壞)도 많았다. 2. $SO_2$ gas접촉에 의하여 엽록소(葉綠素)a가 엽록소(葉綠素)b 보다 쉽게 분해(分解)되었으며 또한 carotinoid도 엽록소(葉綠素)b보다 쉽게 분해(分解)되는 것으로 추정된다. 3. 들깨의 $SO_2$에 의한 엽록소파괴(葉綠素破壞)는 $SO_2$에 의한 직접적(直接的)인 영향(影響)으로 파악되었고, 이 때에 광(光)이 필수적(必須的)으로 필요하며, 물이 광분해(光分解)로 생성(生成)되는 $O_2^-$가 $SO_2$와 함께 엽록소분해(葉綠素分解)에 중심적(中心的)인 역할을 하는 물질이었다.

• 분석과학
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• 제11권5호
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• pp.341-346
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• 1998

$Cu^{2+}$을 2-피리딘카르복살데히드(PyTC)와 반응시켜 $[Cu(PyTC)H_2O)]SO_4$를 얻었다. 이화합물은 1:1 전해질이며 물과 극성 유기 용매에 아주 잘 녹았다. 이 착물의 원소분석, 전기전도도 및 분광학적 데이터에서 이화합물의 구조는 사각평면임을 제시하였다. PyTC를 이용한 Cu(II)의 정량 가능성에 대하여 연구하였다. 구리(II)의 PyTC용액은 pH 4에서 $2.9{\times}10^{-4}M$까지 Beer의 법칙에 따랐다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.675-678
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• 2004

[ $CuAlO_2$ ] was used as P-type transparent conducting oxide. $CuAlO_2$ ceramics was obtained from heating a stoichiometric mixture of $Cu_2O$ and $Al_2OH_3$ at $1200^{\circ}C$ for 6h. $CuAlO_2$ ceramics were doped by the rate of 0, 5, 7 and 10% of the $BeSO_4{\cdot}4H_2O$. Sintered ceramics were investigated by X-ray diffraction (XRD) and electrical measurements. The room temperature conductivity of the ceramics, which were doped with $BeSO_4{\cdot}4H_2O$ 5wt% was of the order of $3.19\times10^{-3}S\;cm^{-1}$, and the density was $4.98g/cm^3$. Therefor the conductivity and density in $BeSO+4{\cdot}4H_2O$ 5wt% were better than other cases. Additionally, Seebeck cofficient measurements revealed that these ceramics were p-type semiconductors and the ceramic conductivity increased with the growth temperature.

• 대한방사선기술학회지:방사선기술과학
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• 제20권2호
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• pp.68-72
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• 1997

Small bowel series using methylcellulose are considered a better technique than using other contrast media considering a significant decrease of transit time of $BaSO_4$ and that of the necessary time for the examination. We investigated the mean transit time of $BaSO_4$, maximum luminal diamenter of small bowel, optical density and flocculation frequency after adminstratting 100 ml of 120% $BaSO_4$ to 20 pts), 150 ml of 70% $BaSO_4$ to 20 pts and 200 ml of $BaSO_4$ with 600 ml of mechylcellulose. It was shown that the technique using 150 ml of 70% $BaSO_4$ had the best result. When we apply a adequate amount of density(w/v%), dosage to pts for small bowel series using MC, we can decrease an examination time and have the better image due to double contrast. It is considered that a more study to lower the density of 70% $BaSO_4$ is necessary.

• 대한한방내과학회지
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• 제21권4호
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• pp.591-595
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• 2000

Objective : This experiment was performed in order to study the effects of Scrophulariae Radix on the injured tracheal tissue induced So, in rats. Methods : Healthy adult male rats weighting about 250g were divided into 4 groups - the Normal group, the Control group, the group of Scrophulariae Radix administration for 5 days after $SO_2$, gas exposure(Sample I), and the group of Scrophulariae Radix administration for 10 days before and for 5 days after $SO_2$, gas exposure(Sample II). Results : In the trachea Control group, the lesion of the ciliated epithelium was severe and the mucus secretion of the respiratory tract was increased significantly. In the trachea of Sample I group, the lesion of the ciliated epithelium and the mucus secretion of the respiratory tract were decreased compared with Control group. In the trachea of Sample II group, the lesion of the ciliated epithelium and the mucus secretion of the respiratory tract were decreased compared with Control and Sample I group. conclusions : According to the above results, Scrophulariae Radix has significant effects on the injuried tracheal tissue caused by $SO_2$ in rats.

• 한국세라믹학회지
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• 제22권6호
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• pp.5-8
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• 1985

Graphite has been oxidized to graphite hydrogen sulfate in concentrated $H_2SO_4$. Anodic oxidation and chemical oxidation of graphite in $H_2SO_4$ generally leads to the formation of intercalation compounds of the ionic salt type through incorporation of $H_2SO_4^-$ions and $H_2SO_4$ molecules into the graphite. Several other reactions also accur at various points of the charging cycle. But there is no satisfactory kinetics and mechanism of intercalationin graphite. We have studied them with anodic oxidation and chemical oxidation. We found six distinct phenomena between 2nd stage and 1st stage in chemical oxidation. We examined them in detail by the following in the measurements electrical oxidation. X-ray diffractions UV-Vis spectroscopy density measurements. We could obtained a equation for kinetic according to the reaction rate from this results and mechanism of intercalation between 2nd stage and 1st stage with hydrogen sulfate in graphite. Three thesis were written for the mechanism of intercalation compounds in graphite with hydrogen sulfate ; first thesis is anodic oxidation second thesis is chemical oxidation and definition of transit phase between 2nd etc the third thesis is the kinetic mechanism of intercalation compounds in graphite with Hydrogen sulfate. This thesis is the first paper among three thesis as anodic oxidation.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2003년도 가을 학술논문집
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• pp.696-700
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• 2003

$H_2SO_4$과 Citric acid 은 다른 화학물질보다 토양으로부터 $^{137}Cs$의 추출효율이 높았다. 오래 저장된 방사능오염 토양으로부터 $^{137}Cs$ 제거효율을 높이기 위해 동전기방법에 의한 토양복원 실험 시 $H_2SO_4$과 citric acid를 첨가제로 사용했다. 실험 컬럼으로부터 방출된 방출수의 평균속도는 $2.0{\times}10^{-2}$cm/min이고, 10일 동안 방출된 토양폐액의 부피는 3.6 Pore Volume이다. 10일간 컬럼 내의 $^{137}Cs$의 제거효율이 54%이었다. 한편, 개발된 모델에 의해 계산된 잔류농도 예측 값은 실험으로부터 구한 결과와 거의 일치했다.