• Title/Summary/Keyword: Nox4

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Antioxidative Effects of Lycium chinense Miller on Cisplatin-induced Nephrotoxicity in Rats (Cisplatin으로 유도된 급성신부전증에 대한 지골피(地骨皮)의 항산화효과)

  • Jung, Yu-Sun;Park, Chan-Hum;Shin, Hyeon-Cheol
    • The Journal of Internal Korean Medicine
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    • v.35 no.1
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    • pp.92-105
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    • 2014
  • Objectives : Cisplatin is a widely used cancer therapy drug. However, nephrotoxicity resulting in increased oxidative stress is a major side effect of cisplatin chemotherapy, thereby limiting its chemotherapeutic use. Lycium chinense Miller (LCM) has been used as a traditional herbal medicine in various febrile and inflammatory diseases such as night sweat, cough, nosebleed, bronchitis, pulmonary tuberculosis, etc. In this study we investigated the protective and antioxidative potential of LCM against cisplatin-induced nephrotoxicity in rats. Methods : Twenty-four 8-week-old male Wistar rats were divided into four groups: normal untreated; cisplatin treatment only; LCM 10 mg/kg plus cisplatin treatment; and LCM 30 mg/kg plus cisplatin treatment. Twenty-four hours after the last cisplatin injection, all the rats were sacrificed, and serological changes were evaluated. The levels of NF-${\kappa}B$ activity and NOX-4, $p47^{phox}$, $p22^{phox}$, COX-2, iNOS, SOD, catalase expressions were analyzed in Western blot analysis. Results : Cisplatin injection caused an increase in the BUN level, which is a reliable indicator of renal toxicity. The levels of BUN, renal ROS, and renal TBARS were significantly reduced in the LCM groups compared with the cisplatin-only groups. The levels of $p47^{phox}$ and $p22^{phox}$, which are NADPH oxidase subunits, were increased in the cisplatin-only groups, whereas they were decreased in the LCM groups. The levels of renal NF-${\kappa}B$ activity and COX-2, iNOS expressions were increased significantly in the cisplatin-only groups compared with the normal groups, whereas they were decreased in the LCM groups. Compared with the cisplatin-only groups, renal GSH and GSH/GSSG increased in the LCM groups. Also, the administration of LCM increased levels of SOD and catalase as compared with the cisplatin-only groups. Conclusions : These results suggest that LCM protects cisplatin-induced nephrotoxicity via a mechanism that may involves the inhibition of oxidative stress by the activation of antioxidants.

A Experimental Study on Nitrous Oxide Formation in Direct Injection Diesel Engine (직접분사식 디젤엔진에서 아산화질소의 생성에 관한 실험적 연구)

  • Yoo, Dong-Hoon
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.21 no.2
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    • pp.188-193
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    • 2015
  • It has been generally recognized that $N_2O$(Nitrous Oxide) emission from marine diesel engines has a close correlation with $SO_2$(Sulfur Dioxide) emission, and diversity of fuel elements using ships affects characteristics of the $N_2O$ emission. According to recent reports, in case of existence of an enough large NO(Nitric Oxide) generated as fuel combustion, effect of the $SO_2$ emission in exhaust gas on the $N_2O$ formation is more vast than effect of the NO. Therefore, $N_2O$ formation due to the $SO_2$ element operates on a important factor in EGR(Exhaust Gas Recirculation) systems for NOx reduction. An aim of this experimental study is to investigate that intake gas of the diesel engine with increasing of $SO_2$ flow rate affects $N_2O$ emission in exhaust gas. A test engine using this experiment was a 4-stroke direct injection diesel engine with maximum output of 12 kW at 2600rpm, and operating condition was set up at a 75% load. A standard $SO_2$ gas with 0.499%($m^3/m^3$) was used for changing of $SO_2$ concentration in intake gas. In conclusion, the diesel fuel included out sulfur elements did mot emit the $SO_2$ emission, and the $SO_2$ emission in exhaust gas according as increment of the $SO_2$ standard gas had almost the same ratio compared with $SO_2$ rate in mixture inlet gas. Furthermore, the $N_2O$ element in exhaust gas was formed as $SO_2$ mixture in intake gas because increment of $SO_2$ flow rate in intake gas increased $N_2O$ emission. Hence, diesel fuels included sulfur compounds were combined into $SO_2$ in combustion, and $N_2O$ in exhaust gas should be generated to react with NO and $SO_2$ which exist in a combustion chamber.

A Study on the Characteristics Measurement of Main Engine Exhaust Emission in Training Ship HANBADA (실습선 한바다호 주기관 배기가스 배출물질 특성 고찰에 관한 연구)

  • Choi, Jung-Sik;Lee, Sang-Deuk;Kim, Seong-Yun;Lee, Kyoung-Woo;Chun, Kang-Woo;Nam, Youn-Woo;Jung, Kyun-Sik;Park, Sang-Kyun;Choi, Jae-Hyuk
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.19 no.6
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    • pp.658-665
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    • 2013
  • In this study, we measured particulate matter(PM) which emerged as the hot issue from the International Maritime Organization(IMO) and the exhaust emission using HANBADA, the training ship of Korea Maritime University. In particular, the PM was obtained with TEM grid. PM structure was observed by electron microscopy. And exhaust gases such as NOx, $CO_2$, and CO were measured using the combustion gas analyzer(PG-250A, HORIBA). The results of this study are as follows. 1) When the ship departed from the port, the maximum difference in PM emissions were up to 30 % due to the Bunker Change. 2) Under the steady navigation, emission of PM was $1.34mg/m^3$ when Bunker-A is changing L.R.F.O(3 %). And, at the fixed L.R.F.O (3 %), emission of PM was $1.19mg/m^3$. When the main engine RPM increased up to 20 % with fixed L.R.F.O(3 %), emission of PM was $1.40mg/m^3$. When we changed to low quality oil(L.R.F.O(3 %)), CO concentration from main engine increased about 16 %. On the other hand, when the main engine RPM is rising up to 20 %, CO concentration is increased more than 152 percent. These results imply that the changes of RPM is a dominant factor in exhaust emission although fuel oil type is an important factor. 3) The diameter of PM obtained with TEM grid is about $4{\sim}10{\mu}m$ and its structure shows porous aggregate.

National Management Measures for Reducing Air Pollutant Emissions from Vessels Focusing on KCG Services (선박 대기오염물질 배출 현황 및 저감을 위한 국가 관리 대책 연구: 해양경찰 업무를 중심으로)

  • Lee, Seung-Hwan;Kang, Byoung-Yong;Jeong, Bong-Hun;Gu, Ja-Yeong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.26 no.2
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    • pp.163-174
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    • 2020
  • Particulate matter levels are rapidly increasing daily, and this can affect human health. Therefore, air pollutant emissions from sea vessels require management. This study evaluates the status of air pollutants, focusing on air pollutant emissions from the vessels of the Korea Coast Guard (KCG), and proposes national management measures to reduce emissions. According to a report recently released (2018) by the National Institute of Environmental Research (NIER), emissions from vessels constituted 6.4 % of the total domestic emissions, including 13.1 % NOx, 10.9 % SOx, and 9.6 % particulate matter (PM10/PM2.5). Among the rates of pollutant emission from vessels, the emission rates of domestic and overseas cargo vessels were the highest (50.6 %); the ratio of fishing boats was 42.6 %. With respect to jurisdictional sea area, 44.1 % of the emissions are from the south sea, including the Busan and Ulsan ports, and 24.8 % of the emissions are from the west sea, including the Gwangyang and Yeosu ports. The KCG inspects boarding lines to manage emission conditions and regulate air pollutant emissions, but it takes time and effort to operate various discharge devices and measure fuel oil standards. In addition, owing to busy ship schedules, inspection documents are limited in terms of management. Therefore, to reduce the air pollutant emissions of such vessels, regulations will be strengthened to check for air pollutants, and a monitoring system based on actual field data using KCG patrol ships will be established, for each sea area, to manage the emissions of such vessels. Furthermore, there is a need for technological development and institutional support for the introduction of environmentally friendly vessels.

BVOCs Estimates Using MEGAN in South Korea: A Case Study of June in 2012 (MEGAN을 이용한 국내 BVOCs 배출량 산정: 2012년 6월 사례 연구)

  • Kim, Kyeongsu;Lee, Seung-Jae
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.24 no.1
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    • pp.48-61
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    • 2022
  • South Korea is quite vegetation rich country which has 63% forests and 16% cropland area. Massive NOx emissions from megacities, therefore, are easily combined with BVOCs emitted from the forest and cropland area, then produce high ozone concentration. BVOCs emissions have been estimated using well-known emission models, such as BEIS (Biogenic Emission Inventory System) or MEGAN (Model of Emission of Gases and Aerosol from Nature) which were developed using non-Korean emission factors. In this study, we ran MEGAN v2.1 model to estimate BVO Cs emissions in Korea. The MO DIS Land Cover and LAI (Leaf Area Index) products over Korea were used to run the MEGAN model for June 2012. Isoprene and Monoterpenes emissions from the model were inter-compared against the enclosure chamber measurements from Taehwa research forest in Korea, during June 11 and 12, 2012. For estimating emission from the enclosed chamber measurement data. The initial results show that isoprene emissions from the MEGAN model were up to 6.4 times higher than those from the enclosure chamber measurement. Monoterpenes from enclosure chamber measurement were up to 5.6 times higher than MEGAN emission. The differences between two datasets, however, were much smaller during the time of high emissions. More inter-comparison results and the possibilities of improving the MEGAN modeling performance using local measurement data over Korea will be presented and discussed.

A Study on the Recirculation Flow Characteristics with the Change of Shape in a Flue Gas Recirculation Device using Coanda Nozzle (코안다 노즐을 이용한 배기가스 재순환 장치의 형상에 따른 재순환 유동 특성에 관한 연구)

  • Ha, Ji Soo;Shim, Sung Hun;Kim, Dae Yeon
    • Journal of the Korean Institute of Gas
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    • v.23 no.3
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    • pp.1-6
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    • 2019
  • The purpose of the present study is to elucidate flue gas recirculation device for reduction of nitrogen oxides using coanda nozzle without adopting additional power driving fan in a waste incinerator. The characteristics of the exhaust gas recirculation flow rate and the average temperature change at the outlet of the mixed gas were investigated according to the change of air supply nozzle gap and the position of air supply nozzle. When the gap of the air supply nozzle was changed to 3.22, 4.03, and 4.84 mm, the largest recirculation flow ratio, which is the ratio of exhaust gas recirculation flow rate and air supply flow rate, was 2.227 for the case with 3.22 mm and its mean temperature at outlet was $594.8^{\circ}C$. When the position of the air supply nozzle changes to the front position, neck position, and expansion position of the coanda nozzle neck, the recirculation flow ratios at the forward position and the neck position were nearly almost the same value, 1.843, and 1.696 at the expansion position, their mean temperatures were $559.8^{\circ}C$ and $544.3^{\circ}C$, respectively.

A Study on the Cold Startability and Emission Characteristics of LPG Vehicle According to Test Temperature (시험온도에 따른 LPG 차량의 저온 시동성 및 배출가스 배출특성 연구)

  • Lee, Min-Ho;Kim, Sung-Woo;Kim, Ki-Ho;Ha, Jong-Han
    • Journal of the Korean Institute of Gas
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    • v.18 no.6
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    • pp.7-13
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    • 2014
  • As the interest on the air pollution is gradually rising up at home and abroad, automotive and fuel researchers have been working on the exhaust emission reduction from vehicles through a lot of approaches, which consist of new engine design, innovative after-treatment systems, using clean (eco-friendly alternative) fuels and fuel quality improvement. This research has brought forward various main issues : whether PM emissions should be regulated for diesel and gasoline vehicles and whether gasoline and LPG powered vehicles can be further neglected from PM emission inventories. Finally, the greenhouse gas ($CO_2$, $CH_4$, $N_2O$) regulation has been discussed including automotive emission regulation. The greenhouse gas and emissions (PM) particle of automotive had many problem that cause of ambient pollution, health effects. This paper discussed the influence of LPG fuel on automotive cold startability and exhaust emissions gas. Also, this paper assessed emission characteristics due to the test temperature. These test temperature were performed by dividing the temperature of the test mode and the lowest local temperature in winter. Through this study, the correlation of cold startability, exhaust emission and greenhouse gas emission was analyzed.

The formation of N-Nitrosamine in Commercial Cured Products 2. The effect of cooking methods on N-Nitrosamine formation in commercial Ham and Sausages (시판 식육제품 중 N-Nitrosamine의 생성 제2보. 조리방법이 햄 및 소시지의 N-Nitrosamine 생성에 미치는 영향)

  • 박계란;이수정;신정혜;성낙주;임상선
    • Journal of Food Hygiene and Safety
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    • v.13 no.4
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    • pp.406-411
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    • 1998
  • Representive cured products such as ham and sausage produced in Korea were purchased at retail and cooked using heating tools such as a gas range (GR), an electric range (ER) and electric range after boiled (BE). Changes of N-nitrosamine (NA), nitrate and nitrite in the cured meats containing< $2.0\;\mu\textrm{g}/kg$ of N-nitrosodimethylamine (NDMA) were checked and analyzed during their cooking process. Contents of nitrate and nitrite in ham products prior to cooking were 2.0 and 1.8 mg/kg, respectively; their contents in regular hams were slightly increased, but those of nitrate in press hams were decreased while those of nitrite were increased during its cooking process. Their contents in sausage products were 1.8 and 0.9 mg/kg; those of nitrate were decreased, while nitrite were slightly increased during its cooking process. NDMA detected only NA in all the collected cured products. Changes of NDMA, regardless of cooking methods, tend to drastically increase in all samples after their cooking; Its contents were increased by average 6.0~70.7 times in the GR samples, by average 2.4~39.2 times in the ER samples and by average 7.0~56.3 times in the BE samples. Virtually, the fact that all of this nitrosamine appeared to arise by the action of precursor such as NOx was produced during the cooking of cured products.

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A Study on the Emissions Characteristics of a LPG Vehicle According to Various Test Modes and Ambient Conditions (다양한 시험모드와 환경조건에 따른 LPG 차량의 배출특성 연구)

  • Lee, Min-Ho;Ha, Jong-Han
    • Journal of the Korean Institute of Gas
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    • v.19 no.4
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    • pp.1-7
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    • 2015
  • As the interest on the air pollution is gradually rising up at home and abroad, automotive and fuel researchers have been working on the exhaust emission reduction from vehicles through a lot of approaches, which consist of new engine design, innovative after-treatment systems, using clean (eco-friendly alternative) fuels and fuel quality improvement. This research has brought forward various main issues : whether PM emissions should be regulated for diesel and gasoline vehicles and whether gasoline and LPG powered vehicles can be further neglected from PM emission inventories. Finally, the greenhouse gas regulation has been discussed including automotive emission regulation. The greenhouse gas and emissions of automotive had many problem that cause of ambient pollution, health effects. Based on various test modes and ambient conditions, this paper discusses the characteristics of LPG on exhaust emissions and greenhouse gases. Also, this paper assessed emission characteristics due to the test temperature. These test temperature were performed by dividing the temperature of the test mode and the lowest local temperature in winter. Through this study, the correlation of vehicle test mode and ambient condition, exhaust emission, greenhouse gas emission was analyzed.

The Effect of HCl Gas on Selective Catalytic Reduction of Nitrogen Oxide (질소산화물의 선택적 환원 제거시 염화수소기체가 촉매에 미치는 영향)

  • Choung, Jin-Woo;Choi, Kwang-Ho;Seong, Hee-Je;Chai, Ho-Jung;Nam, In-Sik
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.4
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    • pp.609-617
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    • 2000
  • This study is aimed at investigating an effect of HCl gas on selective reduction of NOx over a CuHM and $V_2O_5-WO_3/TiO_2$ catalyst. SCR process is the most effective method to remove NOx, but catalyst can be deactivated by the acidic gas such as HCl gas which is also included in flue gas from the incinerator. In dry condition of flue gas, the CuHM catalyst treated by HCl gas has shown higher NO removal activity than the fresh catalyst. The activity of the catalyst can be restored by treating at $500^{\circ}C$. On the contrary. $V_2O_5-WO_3/TiO_2$ catalyst is obviously deactivated by HCl and the deactivation increases in proportion to the concentration of HCl gas. The deactivated catalyst is not restored to it's original activity by heat treatment for regeneration. In wet flue gas stream, the CuHM catalyst has shown lower activity than fresh catalyst and $V_2O_5-WO_3/TiO_2$ catalyst was severely deactivated by HCl treatment. The activity loss of catalysts are mainly due to the decrease of Br$\ddot{o}$nsted acid site on the catalyst surface by $NH_3$ TPD. The change of BET surface area of CuHM catalyst after the reaction isn't observed but $V_2O_5-WO_3/TiO_2$ catalyst is observed. The amount of $Cu^{{+}{+}}$ and $V_2O_5$ is decreased after the reaction. From these results, it is expected that CuHM catalyst should be better than $V_2O_5-WO_3/TiO_2$ catalyst for its application to the incineration of flue gas.

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