• 한국환경보건학회지
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• 제21권3호
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• pp.107-114
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• 1995

To assess the contribution of automobile exhaust to indoor and outdoor levels of $NO_2$ around a major trunk road in Tokyo, $NO_2$ levels of 200 homes were measured at living rooms, kitchens and outdoor at each season, from the summer of 1990 to the spring of 1991, $NO_2$ level was measured for four days using diffusion $NO_2$ dosimeter. Outdoor $NO_2$ levels at each season and indoor $NO_2$ levels at seasons when heaters were not used decreased according to the distance from the roadside. The differences between $NO_2$ levels at zone I(within 20m from the roadside) and zone III(beyond 50m) was about 3 ppb. Automobile exhaust seemed to contribute to this difference. At seasons when heaters were used, indoor $NO_2$ levels of the homes equipped with vented heater, decreased according to the distance from the roadside. However, there was no correlation between indoor levels and the distance from the roadside at homes equipped with unvented heater.

• 환경위생공학
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• 제11권3호
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• pp.47-52
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• 1996

Personal exposure levels of $NO_{2}$ for office workers and housewives Living in A-San and neighboring prefectures were measured in two seasons with $NO_{2}$ filter badge. $NO_{2}$ concentrations in indoor and outdoor air in their offices and houses were also measured in the same periods. Personal exposure levels in winter ranged from 13 to 132 ppb and its distribution pattern was remarkably different from the other seasons (15.2-17.9 ppb). This fact suggests that use of heating apparatus affects largely $NO_{2}$ indoor air pollution in winter seasons. Actually, $NO_{2}$ exposure levels of subjects used Kerosene heater (43.6ppb) and gas heater (33.4ppb) were higher than those of subjects unused heating apparatus (18.0ppb). Personal exposure levels of $NO_{2}$ for man and woman Living in the same houses were correlated well each other. The time spent indoors for office workers and housewives were both longer than 22 hour a day. Home staying time was about 60% of total indoor staying time for office workers and 90% or more for housewives. Personal exposure levels were significantly related to indoor exposure levels at home all seasons. Furthermore, personal exposure levels could be estimated from $NO_{2}$ concentrations and staying times in various Living environment.

• Journal of Preventive Medicine and Public Health
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• 제30권3호
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• pp.609-622
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• 1997

부산지역의 한 아파트 단지내 489세대를 대상으로 아파트 실내외의 $NO_2$ 농도를 측정하고 동시에 $NO_2$ 농도의 관련 변수들을 조사하여 양자간의 관련성을 파악하고자 본 연구를 실시하였다. 아파트 실내외의 $NO_2$, 농도는 개인용 $NO_2$, 포집관 (Palmes tube)을 사용하여 1995년 8월 16일 - 8월 25일 (하계)과 1996년 1월 15일 - 1월 29일 (동계)간에, 그리고 가스렌지 근처, 주방, 거실 및 아파트 옥외에서 측정하였다. 본 연구의 결과를 요약하면 다음과 같다. 1) 각 세대의 가스렌지 근처와 주방, 거실 및 실외의 평균 $NO_2$, 농도는 하계는 각각 $25.9{\pm}10.0ppb,\;23.3{\pm}8.0ppb,\;19.9{\pm}6.1ppb$ 및 $19.0{\pm}6.0ppb$이며, 동계는 $34.5{\pm}16.8ppb\;28.2{\pm}13.4ppb,\;25.3{\pm}12.5ppb$ 및 $21.8{\pm}9.8ppb$로서 동하계 공히 부엌의 가스렌지 근처의 $NO_2$, 농도가 최고이었고 하계에 비하여 동계의 실내외 $NO_2$ 농도가 유의하게 높았다. 리 아파트 층수별 $NO_2$ 농도는 하계에는 층수에 따른 $NO_2$, 농도의 유의한 변화가 없었으나, 동계는 16층 이상을 제외하면 층수가 높아짐에 따라 $NO_2$ 농도가 감소하였다. 기 아파트 실내 $NO_2$ 농도의 관련변수는 하계의 경우 층수, 가족수, 1회 식사시 평균 가족수, 취사시 가스렌지 1일 평균 사용횟수, 자연 환기이었고, 동계에는 층수, 가족수, 1회 식사시 평균 가족수, 총 식사 인원수, 식사 횟수, 가족의 총 연령, 취사시 가스렌지 1일 평균 사용 횟수, 조리시 가스렌지 1일 평균 사용 횟수, 호흡기 질환자 유무 등이었다. 4) 아파트 실내 $NO_2$ 농도의 감소 방안으로는 취사 혹은 조리시 환기를 철저히 하고, 완전연소, 연소의 횟수와 시간 단축 및 연료의 대체가 필요하다고 생각한다.

• Journal of Nutrition and Health
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• 제24권2호
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• pp.87-96
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• 1991

This study was undertaken to investigate the effect of the levels of dietary Zn and alcohol consumption on lipid metabolism in Sprague-Dawley male rats weighing 80 to 90g for eight weeks. Ninety rats were divided into nine groups according to Zn levels and alcohol consumption such as no alcohol group[low Zn diet group(<1ppm. LZ) control Zn diet group(30ppm. CZ) high Zn diet group(60ppm, HZ)] 10% alcohol consumption group[the same Zn levels as no alcohol group LZLA, CZLA, HZLA] 20% alcohol consumption group[the same Zn levels as no alcohol group, LZHA, CZHA, HZHA] The results obtained were summarized as following : 1) In the serum total cholesterol increased with increasing dietary Zn levels but decreased with alcohol consumption. HDL-cholesterol decreased with alcohol consumption. Triglyce-ride in alcohol group was higher than no alcohol group. In alcohol group triglyceride increased with decreasing dietary Zn levels. 2) In the liver total lipid in alcohol group was higher than no alcohol group HA group showed a significant increase. Triglyceride increased with alcohol consumption. 3) In the serum and liver Zn content increased with increasing dietary Zn levels but decreased with alcohol consumption.

• 한국대기환경학회지
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• 제3권2호
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• pp.27-32
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• 1987

大氣汚染의 疫學的 硏究의 일부로서 미국내 휴스턴시의 家庭을 對象으로 5가지 主要硏究物質($SO_2$, $NO_2$, CO, $O_3$)에 대한 室內外 濃度를 調査하였다. 室內濃度는 침실, 부엌, 거실에서 調査하였고 室外濃度와 比較하였다. 그 結果 오존을 除外한 각 汚染物質에서 부엌과 거실의 濃度는 室外濃度 보다 높았다. 또한 $NO_2$와 $O_3$를 除外한 각 汚染物質의 室內外 濃度比는 1.8 ~ 2.7을 나타냈다. 특히 家庭 內에서 汚染物質의 室內濃度는 家庭의 住宅構造, 居住者의 吸煙狀況 등에 影響을 받는 것으로 시사되었다.

• 한국대기환경학회지
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• 제24권2호
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• pp.176-188
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• 2008

Anthropogenic emissions of nitrogen oxides and sulfur dioxide in Northeast Asia are of great concern because of their impact on air quality and atmospheric chemistry on regional and intercontinental scales. Satellite remote sensing based on DOAS (Differential Optical Absorption Spectroscopy) technique has been preferred to measure atmospheric trace species and to investigate their emission characteristics on regional and global scales. Absorption spectra obtained by the satellite-born instrument, SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Chartography) have been utilized to retrieve the information of $SO_2$ and $NO_2$ over Northeast Asia. $SO_2$ levels over Northeast Asia were in order of East China, Yellow Sea, South Sea and Korean Peninsula with mean vertical columns of $1.78({\pm}1.0){\times}10^{16}$, $1.11({\pm}0.67){\times}10^{16}$, $0.60({\pm}0.63){\times}10^{16}$, $0.71({\pm}0.65){\times}10^{16}\;molecules/cm^2$, respectively. $NO_2$ levels were in order of East China, Yellow Sea, Korean Peninsula, and South Sea with mean vertical columns of $1.2({\pm}0.56){\times}10^{16}$, $0.38({\pm}0.19){\times}10^{16}$, $0.48({\pm}0.28){\times}10^{16}$, $0.26({\pm}0.16){\times}10^{16}\;molecules/cm^2$, respectively. High levels of $SO_2$ and $NO_2$ were observed over East China, in particular in winter by the contribution of heating fuel combustion exhausts. The $SO_2$ and $NO_2$ levels over East China were the highest in January with 34% and 42% higher over the annual means. Low levels of $SO_2$ ranged over Korean peninsula, while $NO_2$ levels were relatively high, in particular in winter. The $SO_2$ and $NO_2$ levels over Yellow Sea were relatively higher compared to those over Korean peninsula and South Sea, which could be mainly attributed to their transport from East China.

• Geosystem Engineering
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• 제21권5호
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• pp.243-250
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• 2018

This study investigated nitrite ($NO_2{^-}$) accumulation due to FA (Free Ammonia: $NH_3$) inhibition in an anaerobic-aerobic-anoxic (AOA) process reactor to mainly treat wastewater containing 302-610 mg/L of $NH_3/NH_4{^+}-N$. Based on an experimental operation focusing on the nitrification, it was observed that $NO_2{^-}$ was accumulated in the aerobic nitrification zone as pH increased, due to inhibition of $NO_2{^-}$ conversion to $NO_3{^-}$ by FA. This result implied FA inhibition to NOB ($NO_2{^-}$-Oxidizing Bacteria) for converting $NO_2{^-}$ to $NO_3{^-}$. The objective of this study is to develop a feasible monitoring procedure for early detection of the FA inhibition toward $NO_2{^-}$ accumulation and poor nitrification. Thus, in order to rapidly assess FA concentrations, an $NH_3$ probe was utilized to measure $NH_3$ concentrations together with applying a simple model prediction using the measured $NH_4{^+}$ concentrations, the Henry's law constant of $NH_3$ and measured pH. The predictive model $NH_3$ levels were verified by a good correlation (89%) with the corresponding measured data, but the model prediction underestimated FA concentrations at less than 7.4 and a little overestimated at pH above 7.5. Interestingly, accumulated $NO_2{^-}$ levels were roughly correlated with FA levels that were observed at delayed time points. This reflects the detected FA levels can be good indicators of $NO_2{^-}$ levels with some delayed time. $NO_2{^-}$ accumulation started at measured FA concentrations of higher than approximately 3 mg/L and ceased below that FA level.

• 환경위생공학
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• 제14권2호
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• pp.68-74
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• 1999

The atmospheric concentrations of Nitrogen Dioxide ($NO_2$) and Total Suspended Particulates (TSP) at the traffic road side were measured n Asan area, Choongchumg-namdo during May 1998 and January, 1999.The results of the study are as follows;1. The aversge value of airbone $NO_2$ and TSP levels were 28.5ppb and 5.9mg/me in Asan area. 2. The concentration distribution of NO2 and TSP is high for the season of winter. On a daily pattern, somewhat high value is appeared in the afternoon. 3. For the station, terminal, and Shinchang, the average value of $NO_2$ is 33.6ppb, 27.9ppb and 24.1ppb in sequence, and the ones of TSP is 6.3mg/m3, 6.0mg/m3 and 5.3mg/m3 in order.4. The high levels of $NO_2$ and TSP were positively related to traffic volume.

• 한국환경보건학회지
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• 제34권3호
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• pp.183-187
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• 2008

Indoor air quality can be affected by indoor sources, ventilation, decay, and outdoor levels. Various indoor and out-door combustion sources produce nitrogen dioxide ($NO_2$), which is a by-product of high temperature fossil fuel combustion. Especially, the presence of gas ranges and smoking have been identified as major factors contributing to indoor $NO_2$ exposures. In this study, we compared an industrial complex area with a country area by assessing the personal exposure to $NO_2$with measurements of indoor and outdoor $NO_2$ levels in residences and by house characteristics and questionnaire. Personal exposure concentrations were significantly correlated with indoor $NO_2$ concentrations of residences in both the industrial complex area and the country area with correlation coefficients of 0.561 and 0.664, respectively, compared to outdoors. Multiple regression analysis, indicated that indoor $NO_2$ levels in residences were only affected by outdoor levels (p = 0.000) in spite of higher indoor sources such as smoking. Therefore, it is suggested that outdoor air quality as well as indoor air quality should be considered in the reduction of the personal exposure to air pollutants.

• 대한핵의학회지
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• 제6권2호
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• pp.7-20
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• 1972

Experimental radiation nephritis was produced in 15 rabbits by X-irradiation. About $2,000{\gamma}$ (tissue doses) were given to both kidneys of a rabbit in 5 days. Other tissues and organs except both kidneys were protected with 2mm thickened lead plates. 5 weeks after the last irradiation, blood pictures, blood pressures, B.U.N., serum creatinine, Ca, Mg, Fe levels and serum erythropoietin activity of the irradiated rabbits were studied. After finishing above studies, rabbits were sacrificed and both kidneys were removed and examined histopathologically. Same laboratory and pathological studies were performed in 6 control rabbits. In this study, the author obtained following results. 1) Both kidneys of rabbitis with experimental raditation nephritis showed marked histopathological changes, i.e.: renal tubules showed diffuse cloudy swelling, impacted intraluminal hyaline casts and focal precipitations of lime salts on the tubular epithelium. Diffuse interstitial fatty necrosis and various degrees of fibrotic infiltrations on the interstitium were also seen in association with focal lymphocytic infiltrations. Hyaline degenerations were observed on the glomeruli and small vessels. 2) Experimental radiation nephritis rabbits showed marked lowering in R.B.C. counts, decreased hemoglobin levels, low hematocrit values and leucopenia in comparison with those of control rabbits. (P<0.01). (Table 1 & 2). 3) Mild proteinuria were observed in experimental radiation nephritis in rabbits. 4) The levels of B.U.N. and serum creatinine increased in experimental radiation nephritis. (P<0.01). (Table 1,3 & 4) 5) The levels of serum Ca and Mg Showed no statistical difference in comparison with those of control rabbits. (P>0.05) (Table 3 & 4). 6) No statistical correlations were observable between the levels of B.U.N. and Hb. values. (${\gamma}=-0.223$) No close correlations (${\gamma}=-0.328$) were noticed between the levels of B.U.N. and serum iron levels. 7) Erythropoietin activity (R.B.C. $^{59}Fe$ Incorporation) was measured by the modified Fried method. No change in its activity was noticed in radiation nephritis group comparing with that of the control group. (P>0.05). (Table 1,3 & 5). 8) Carotid artery blood pressures showed also no difference. (P>0.05). (Table 1 & 2).