• 한국작물학회:학술대회논문집
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• 한국작물학회 1993년도 추계 학술대회지
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• pp.38-39
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• 1993

• 한국작물학회:학술대회논문집
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• 한국작물학회 1996년도 춘계 학술대회지
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• pp.94-95
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• 1996

• 한국작물학회:학술대회논문집
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• 한국작물학회 1994년도 춘계 학술대회지
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• pp.98-99
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• 1994

• Corrosion Science and Technology
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• 제3권6호
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• pp.251-256
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• 2004

Exposure of zinc samples in simulated acid rain solution (SARS) was investigated under a periodic wet-dry conditions using an AC impedance technique. The periodic wet and dry exposure consisted of the immersion of zinc samples in SARS for one hour followed by exposure to 7 hours drying at 60% RH. Phases of the corrosion products were indentified by X-ray diffraction (XRD). The influence of relative humdiity (RH), temperature, and surface inclination on the atmospheric corrosion of zinc is described. The reciprocal of polarization resistance (1/Rp) decreases rapidly during the initial stages then slowly and eventually attains a steady state as exposure time progresses. The average of reciprocal of polarization resistance per cycle, (ARPR) was calculated and found to decrease as number of exposure cycle increases. An increase of temperature enhances the corrsion rate of zinc. The values of ARPR, of a sample inclined at 30 o are lower than those for a sample oriented horizontally. The experiment result shows a pronounced dependence of reciprocal of polarization resistance on RH. Exposure in the presence of carbonate anions gives rise to more protective corrosion products than in nitrate anion solution. The corrosion mechanism during the initial stages of atmospheric zinc corrosion under wet-dry cyclic conditions is suggested.

• 한국산림과학회지
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• 제76권2호
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• pp.99-108
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• 1987

인공산성우(人工酸性雨)가 은행(銀杏)나무의 종자발아율(種子發芽率)과 유묘(幼苗)의 생장(生長)에 미치는 영향(影響)을 구명(究明)하기 위하여, 천연강우(天然降雨)를 차단(遮斷)하고 묘포토양(苗圃土壤), 혼합토양(混合土壤) 및 사질토양(砂質土壤)에 각각 분식(盆植)된 은행(銀杏)나무 종자(種字)와 유묘(幼苗)(1-0, half-sib)에 인공산성우(人工酸性雨)(황산(黃酸)과 질산(窒酸)을 3:1, v/v로 혼합(混合)하여 수돗물로 희석한 pH 2.0, 3.0, 4.0 및 5.0)와 수돗물(pH 6.4)을 생육기간중(生育期間中)(1985년(年) 4월(月) 28일(日)~10월(月) 19일(日) 및 1986년(年) 4월(月) 12일(日)~8월(月) 19일(日))에 주(週) 3회(回), 매회(每回) 5mm씩 처리(處理)하여 얻어진 결과(結果)는 다음과 같다. 1. 은행(銀杏)나무 종자(種字)의 발아(發芽)는 야외실험(野外實驗)에서는 pH 2.0 처리구(處理區)에서 발아율(發芽率)이 감소(減少)했으며, 실내실험(室內實驗)에서는 pH 2.0 및 3.0 처리구(處理區)에서의 발아율(發芽率)이 대조구(對照區)에 비하여 현저히 낮아졌다. 2. 2년생(年生)(1-1) 묘목(苗木)의 경우, 개체당(個體當) 건중량(乾重量), 지상부(地上部) 및 지하부(地下部) 건중량(乾重量)은 토양간(土壤間)에 그리고 pH 간(間)에 유의차(有意差)가 있었으며, 신초생장(新梢生長)은 pH 간(間)에만 유의차(有意差)가 인정(認定)되었다. 3. 1년생(年生)(1-0) 묘목(苗木)의 경우, 묘고(苗高), 개체당(個體當) 총건중량(總乾重量), 수간일지조(樹幹一枝條) 건중량(乾重量)이 pH 간(間)에 각각 유의성(有意性)이 인정(認定)되었다.

• 한국환경농학회지
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• 제27권3호
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• pp.279-284
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• 2008

We investigated whether carboxylate exudation of Brassica pekinensis Rupr. was affected by nitrate deposition from simulated acid rain. A gas chromatographic (GC) analysis was employed for the determination of low molecular weight organic acids (LOA) in rhizosphere soils, bulk soil, roots and leaves of Brassica pekinensis Rupr.. Rhizosphere soils were collected after 8 weeks of plant growth by first removing the bulk soil from the root system and then by mechanical move off the rhizosphere soil that adhered to the root surface with soft brush. Soil and plant materials were simultaneously extracted with the mixture of methanol and sulfuric acid (100:7, v/v). Seven organic acids, oxalic, malonic, fumaric, succinic, maleic, L-malic and citric acid were identified and quantified by GC equipped with FID. Oxalic, L-malic, and citric acids were found in both the bulk and rhizosphere soils, while most LOAs were not detected in the control treatment. On the contrary, except maleic acid, all other organic acids were detected in the leaves and roots of cabbages treated with nitrate deposition.

• Applied Science and Convergence Technology
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• 제26권6호
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• pp.218-222
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• 2017

This study was conducted to remove $NO_x$, which is the main cause of fine dust and air pollution as well as acid rain. $NO_x$ was tested using 3% NO (diluted in He) as a simulated gas. Experiments were sequentially carried out by oxidizing NO to $NO_2$ and absorbing $NO_2$. Especially, we focused on the changes of NO oxidation according to both oxidant ($NaClO_2$) concentration change (1~10 M) and oxidant pH change (pH = 1~5) by adding HCl. In addition, we tried to suggest a method to improve $NO_2$ absorption by conducting $NO_2$ reduction reaction with reducing agent (NaOH) concentration (40~60%). It was found that NO removal efficiency increased as both concentration of oxidant and flow rate of NO gas increased, and NO decreased more effectively as the pH of hydrochloric acid added to the oxidant was lower. The $NO_2$ adsorption was also better with increasing NaOH concentration, but the NO removal efficiency was ~20% lower than that of the selective NO reduction. Indeed, this experimental method is expected to be a new method that can be applied to the capture and removal of fine dust caused by air pollution because it is a method that can easily remove NO gas by a simple device without expensive giant equipment.

• 한국토양비료학회지
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• 제26권4호
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• pp.308-313
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• 1993

산성(酸性)비에 의한 작물(作物)의 조직변화(組織變化)를 알아보기 위해 인공산성(人工酸性)비(pH 6.0, 5.0, 4.0, 3.0 및 2.0)를 처리(處理)한 참깨 잎의 조직(組織)을 전자현미경(電子顯微鏡)(SEM, TEM)을 이용(利用)하여 조사(調査)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 인공산성(人工酸性)비에 의한 참깨 잎의 가시적(可視的) 피해증상(被害症狀)은 pH 2.0의 경우(境遇)에는 1회(回) 처리후(處理後), pH 3.0의 경우(境遇)는 7회(回) 처리후(處理後) 나타났으나 pH 4.0 이상(以上)의 처리(處理)에서는 10회(回) 처리후(處理後)까지 나타나지 않았다. 2. Non-glandular trichome는 pH 3.0 이상(以上)에서는 피해(被害)가 없었으나 pH 2.0 처리구(處理區)에서는 피해(被害)가 발견(發見)되었다. 3. 엽맥(葉脈)을 따라 존재(存在)하는 glandular trichome는 무처리구(無處理區)와 대조구(對照區)(pH 6.0)에서는 피해(被害)가 없었으나 pH 5.0 이하(以下)의 보든 처리(處理)에서 피해(被害)가 발견(發見)되었다. 4. 엽록체붕괴(葉綠體崩壞)는 pH 2.0의 인공산성(人工酸性)비가 처리(處理)된 참깨 잎에서만 일어났다.

• 한국작물학회지
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• 제39권6호
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• pp.556-563
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• 1994

작물의 영양생장기에 처리된 산성비에 대한 내성과 피해양상을 알기 위하여 벼, 옥수수, 콩, 팥, 고추, 토마토, 참깨, 밀, 보리, 배추, 무, 상추, 시금치 등 13개 작물을 파종 후 20일에 인공산성비 (pH 3.0, 4.5, 6.0)를 10mm씩 2일 간격으로 15회 처리한 후 작물의 형태적 및 생리적 변화를 조사분석한 결과를 요약하면 다음과 같다. 1. pH가 3.0이상일 때 인공산성비 처리에 의한 가시적 피해는 없었다. 2. 전자현미경상 조직의 피해는 없었으나 참깨, 콩, 팥의 엽록체내에 염색정도가 옅은 지질과립이 나타났다. 3. 엽신의 엽록소 함량은 팥에서는 증가하였으나, 벼, 토마토, 시금치에서는 감소되었고, 다른 작물은 인공산성비 처리간에 차이가 없었다. 4. 광합성은 팥에서 증가되었고, 배추와 보리에서는 감소하였으나 다른 작물은 인공산성비의 영향이 없었다. 5. pH 2.0의 인공산성비를 처리하였을 때 가시적 피해가 적은 작물은 벼, 옥수수, 참깨, 토마토, 밀, 보리 등이었으며, 피해가 큰 작물은 팥, 고추, 콩, 배추, 상추, 무, 시금치 등이었다.

• Journal of Plant Biology
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• 제37권3호
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• pp.309-316
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• 1994

To make regional comparisons of water status of pitch pine, the temporal changes of water status in pitch pine were investigated at different areas; urban Seoul (heavily polluted area), surburb of Seoul (lightly polluted area), and rural area (control). The effects of air pollutants, acid rain and chemical properties of soil on water deficit in pitch pine were also investiaged. Water content of needles growing at polluted areas were usually lower than that at unpolluted area. Water saturation deficit of needles growing at polluted areas were usually higher than that at unpolluted area especially in dry season. These results indicated that water in needles growing at polluted areas were usually more deficient than that at unpolluted area, and were more deficient in April than other months. At polluted areas, the older the needles were, the more quickly transpirated the water in the needle was. At unpolluted areas, however, water in old needles was not so quickly transpirated as those at polluted areas. Water potential of needles of pitch pine seedlings treated with simulated acid rain (SAR) of pH 3.5 decreased more quickly than that of needles treated with SAR of pH 5.6. Loss of water through epicuticular layer was greater in the following order: magnesium deficiency＋100 $\mu$M aluminium>100$\mu$M aluminium>magnesium deficiency>control. In addition to Mg deficiency and Al toxicity, growth decline of pitch pine widely occurring in polluated Seoul could to a large extent be due to cuticle degredation and abnormal vertical distribution of fine roots, which lead to water stress, particularly in dry seasons.