• Title/Summary/Keyword: $NO_x$Concentration

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색소 과다 침착만으로 조기 발견한 소아 부신백질이영양증 1례

  • Park, Seon-Hyeong;Hong, Yong-Hui
    • Journal of The Korean Society of Inherited Metabolic disease
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    • v.14 no.2
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    • pp.195-199
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    • 2014
  • The X-linked adrenoleukodystrophy (X-ALD) is a peroxisomal disease by defects of ABCD1 gene on chromosome Xq28 leading to accumulation of saturated very long chain fatty acids (VLCFA), progressive demyelination and adrenal insufficiency. A 4-year-old boy was visited hospital with the chief compliant of hyperpigmentation beginning at 2-years old. Serum adrenocorticotropic hormone (ACTH) and cortisol concentration were compatible with adrenal insufficiency. The elevated plasmatic concentration of VLCFA and genotype analysis with sequencing of ABCD1 gene established the diagnosis of X-ALD. Brain MRI showed no abnormal high signal intensity on the white matter. Steroid replacement was started with good response. He initiated Lorenzo's oil with restriction of VLCFA by reducing the intake of fatty foods. The author highlight the importance of suspecting of X-ALD in the etiology of primary adrenal insufficiency as the first sign of the disease.

Plasmid DNA damage by neutron and ${\gamma}-$ radiation (중성자 및 ${\gamma}-ray$ 조사에 따른 plasmid DNA 의 손상 관찰)

  • Cheon, Gi-Jeong;Kim, Myeong-Seop;Seo, Won-Suk
    • Proceedings of the Korean Nuclear Society Conference
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    • 2004.10a
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    • pp.1212-1213
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    • 2004
  • The plasmid was used pBR 322 and ${\varphi}X174$ RF DNA. In neutron experiment, damage of pBR 322 and ${\varphi}X174$ RF DNA were observed according to increasing concentration of BSH and neutron dose. Damage of plasmid DNA appeared obvious by increasing of BSH and neutron irradiation. In ${\gamma}-$ radiation experiment, it was carried out like above neutron experiment but damages of two plasmid appeared no differences from the control unlike neutron result.

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A Quantitative Analysis of the Effect of Ocean Emissions on the Simulated Ozone Concentration in South Korea (국내 오존 모의 농도에 대한 해양 배출량의 영향 정량 분석)

  • Park, Jaehyeong;Jeon, Wonbae;Mun, Jeonghyeok;Kim, Dongjin
    • Journal of Environmental Science International
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    • v.30 no.5
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    • pp.413-424
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    • 2021
  • In this study, we quantitatively analyze the effect of ocean emission sources on the simulated O3 concentrations in South Korea using the community multi-scale air quality (CMAQ) model. To analyze changes in O3 concentrations by ocean emissions, two different CMAQ simulations considering ocean emissions (OE case) and without considering ocean emissions (NE case) were conducted during the Korea-United States air quality (KORUS-AQ) campaign period (May-June 2016). The changes in the simulated O3 concentrations due to the effect of ocean emissions (OE case-NE case) appeared mostly in the ocean areas (+1.201 ppbv). The effect of ocean emissions was positive during the daytime (+1.813 ppbv), but negative during the nighttime (-0.612 ppbv). Analysis using the integrated process rate (IPR) confirmed that the increase or decrease in O3 concentration by ocean emissions was mainly due to chemical processes. Further analysis using the integrated reaction rate (IRR) showed that the daytime increase in O3 concentration was mainly attributable to the increased O3 production via O + O2 + M → O3 + M reaction as photolysis of NO2 increased due to the added ocean emissions. The nighttime decrease in O3 concentration was mainly due to the increased O3 titration by NO (NO + O3 → O2 + NO2) due to the increased NO emission. These results indicate that the changes in the concentration O3 in the sea area by the effect of ocean emissions are mainly due to increased NOx emissions. However, there could be a number of uncertainties in ocean emissions data used in this study, thus continuous comparative research using the most updated data will need to be carried out in the future.

Computational Fluid Dynamics(CFD) Simulation and in situ Experimental Validation for the Urea-Based Selective Non-Catalytic Reduction(SNCR) Process in a Municipal Incinerator (생활폐기물 소각장 2차 연소로에서 요소용액을 이용한 선택적무촉매환원 공정에 대한 전산유체역학 모사 및 현장 검증)

  • Kang, Tae-Ho;Nguyen, Thanh D.B.;Lim, Young-Il;Kim, Seong-Joon;Eom, Won-Hyeon;Yoo, Kyung-Seun
    • Korean Chemical Engineering Research
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    • v.47 no.5
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    • pp.630-638
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    • 2009
  • A computational fluid dynamics(CFD) model is developed and validated with on-site experiments for a urea-based SNCR(selective non-catalytic reduction) process to reduce the nitrogen oxides($NO_x$) in a municipal incinerator. The three-dimensional turbulent reacting flow CFD model having a seven global reaction mechanism under the condition of low CO concentration and 12% excess air and droplet evaporation is used for fluid dynamics simulation of the SNCR process installed in the incinerator. In this SNCR process, urea solution and atomizing air were injected into the secondary combustor, using one front nozzle and two side nozzles. The exit temperature($980^{\circ}C$) of simulation has the same value as in situ experiment one. The $NO_x$ reduction efficiencies of 57% and 59% are obtained from the experiment and CFD simulation, respectively at NSR=1.8(normalized stoichiometric ratio) for the equal flow rate ratio from the three nozzles. It is observed in the CFD simulations with varying the flowrate ratio of the three nozzles that the injection of a two times larger front nozzle flowrate than the side nozzle flowrate produces 8% higher $NO_x$ reduction efficiency than the injection of the equal ratio flowrate in each nozzle.

Effects of Joaguihwan (JGH, 左歸丸) Extract on Changes of Anti-oxidation, Anti-inflammatory in RAW 264.7 Cells and on Factors Related with Bone Metabolism in Skull Fractured Rat (좌귀환(左歸丸)이 산화적 손상, 염증 및 골절유합 관련 인자에 미치는 영향)

  • Li, Yu Chen;Oh, Min-seok
    • Journal of Korean Medicine Rehabilitation
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    • v.26 no.3
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    • pp.31-49
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    • 2016
  • Objectives The study was designed to evaluate the healing effects of Joaguihwan (JGH) extract on Anti-oxidation, Anti-inflammatory in RAW 264.7 Cells and factors related with bone metabolism in skull fractured Rat. Methods The fracture healing effect of JGH was measured by scavenging activities of1,1-diphenyl-2-picryl-hydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and nitric oxide (NO) in RAW 264.7 cells. The inhibitory effect against the production of inflammatory mediators including interleukin-$1{\beta}$ (IL-$1{\beta}$), interleukin-6 (IL-6), tumor necosis factors-${\alpha}$ (TNF-${\alpha}$) expression was inhibited in RAW 264.7 cells was experimented using JGH. The effects of JGH on healing fractured rats was measured by osteocalcin, calcitonin, CTXII, TGF-${\beta}$, BMP-2, Insulin, ALP in the serum. and was checked every 3 weeks from 0 week to 6week using x-ray. Results 1. DPPH free radica and ABTS scavenging activity of JGH were increased according to concentration of JGH in RAW 264.7 Cells. 2. In the experiment, NO, IL-$1{\beta}$, IL-6, TNF-${\alpha}$ all showed decrease, in general. Especially NO and IL-$1{\beta}$ showed significantly decrease at a concentration of 10, 100 (${\mu}g/ml$). 3. In the production of osteocalcin in the serum, JGH 200, 400 mg/kg experimental group showed significant increased effect at 2 weeks. 4. In the production of calcitonin in the serum. JGH 200 mg/kg experimental group showed significant increased effect at 4, 6 weeks. JGH 400 mg/kg experimental group showed significant increased effect at 2, 4, 6 weeks. 5. In the production of CTX, TGF-${\beta}$, BMP-2 in the serum, experimental group showed increased effect. but no significant effect. 6. In the production of insulin in the serum. JGH 200, 400 mg/kg experimental group showed significant decrease effect at 2, 4, 6 weeks. 7. In the production of ALP in the serum. JGH 200 mg/kg experimental group showed significant increased effect at 2, 4, 6 weeks. JGH 400 mg/kg experimental group showed significant increased effect at 4, 6 weeks. 8. In the change of X-ray, the experimental group showed better healing effects on skull fractured rats than control group. Conclusions From above results, JGH showed healing effect on Anti-oxidation, Anti-inflammatory in RAW 264.7 Cells, factors related with bone metabolism in the serum of skull fractured rat and x-ray, which is expected to be applied in clinics.

Selective antibacterial activity of quercetin against Xanthomonas campestris (Quercetin의 식물병원성 세균인 Xanthomonas campestris에 대한 선택적 살균활성)

  • Kim, Jeong Yoon;Kim, Ju Yeon;Seo, Sung-Jun;Seo, Min-Kyung;Kim, Jin-Seong;Kang, Sang-Woo;Oh, Kyeong-Yeol;Kim, Jin-Hyo
    • Journal of Applied Biological Chemistry
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    • v.65 no.2
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    • pp.101-105
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    • 2022
  • Quercetin is a major flavonoid in onion and known to antimicrobial activity against several pathogenic bacteria. However, the antibacterial activity of quercetin had not been evaluated against plant pathogenic Xanthomonas campestris and Erwinia carotovora. In here, quercetin and the solvent extracts of onion were investigated their antibacterial activity. Quercetin showed a selective inhibitory activity against X. campestris, and the minimal inhibition concentration (MIC) and minimal bactericidal concentration of quercetin were 15.6 and 20.0 ㎍ mL-1 respectively. Otherwise, it showed no inhibitory activity against E. carotovora, and no the additive and the synergistic effects with streptomycin on X. campestris. And the EtOAc extract from the peel of onion that contained quercetin showed 2-fold lower MIC (500 ㎍ mL-1) than the EtOH extract, thus EtOAc was suggested as the extraction solvent for quercetin from onion peel.

A Study on Numerical Simulation of Gaseous Flow in SCR Catalytic Filter of Diesel Exhaust Gas Aftertreatment Device

  • Bae, Myung-Whan;Syaiful, Syaiful;Mochimaru, Yoshihiro
    • Journal of Advanced Marine Engineering and Technology
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    • v.34 no.3
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    • pp.360-368
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    • 2010
  • A SCR catalytic filter system is used for reducing $NO_x$ and soot emissions simultaneously from diesel combustors. The amount of ammonia (as a reducing agent) must be controlled with the amount of $NO_x$ to obtain an optimal $NO_x$ conversion. Hence, gas mixing between ammonia and exhaust gases is vital to ensure that the SCR catalyst is optimally used. If ammonia mass distribution is not uniform, slip potential will occur in rich concentration areas. At lean areas, on the other hand, the catalyst is not fully active. The better mixing is indicated by the higher uniformity of ammonia mass distribution which is necessary to be considered in SCR catalytic filter system. The ammonia mass distributions are depended on the flow field of fluids. In this study, the velocity field of gaseous flow is investigated to characterize the transport of ammonia in SCR catalytic filter system. The influence of different injection placements on the ammonia mass distribution is also discussed. The results show that the ammonia mass distribution is more uniform for the injector directed radially perpendicular to the main flow of inlet at the gravitational direction than that at the side wall for both laminar (Re = 640) and turbulent flows (Re = 4255). It is also found that the mixing index decreases as increasing the heating temperature in the case of ammonia injected at the side wall.

Quantitative Assessment on Contributions of Foreign NOx and VOC Emission to Ozone Concentrations over Gwangyang Bay with CMAQ-HDDM Simulations (CMAQ-HDDM을 이용한 광양만 오존 농도의 국외 기여도 분석)

  • Bae, Changhan;Kim, Byeong-Uk;Kim, Hyun Cheol;Kim, Soontae
    • Journal of Korean Society for Atmospheric Environment
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    • v.34 no.5
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    • pp.708-726
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    • 2018
  • In this study, we examined the contribution of nitrogen oxides and volatile organic compounds emitted from China and Japan to ozone concentrations over Gwangyang-bay, South Korea. We used a chemical transport model, Community Multi-scale Air Quality model, and its instrumented sensitivity tool, High-order Decoupled Direct Method. Intercontinental Chemical Transport Experiment-Phase B 2006 for East Asia and Clean Air Policy Support System 2007 emissions inventories for South Korea were used for the ozone simulation. During the study period, May 2007, the modeled maximum daily 8-hr average ozone concentration among seven air quality monitors in Gwangyang-bay was 68.8 ppb. The contribution of $NO_x$ emissions from China was 19.5 ppb (28%). The highest modeled ozone concentrations and Chinese contributions appeared when air parcels were originated from Shanghai area. The observed 8-hr average ozone concentrations in Gwangyang Bay exceeded the national ambient air quality standard (60 ppb) 203 times by daytime and 56 times by nighttime during the period. It was noticed that many exeedances happened when contribution of Chinese emissions to ozone concentrations over the area increased. Sensitivity analysis shows that a reduction in Chinese $NO_x$ and VOC emissions by 15% could lessen the total exceedance hours by 24%. This result indicates that high ozone concentrations over Gwangyang-bay are strongly enhanced by Chinese emissions.

A Study on the Thermal and Pollution Performances of the Heating Boilers with NG-H2 Mixture Ratio (난방용 보일러에서 NG-H2 혼소율에 따른 열 및 공해 성능의 검토)

  • SEO, JUNSUN;KIM, YOUNG-JIC;PARK, JUNKYU;LEE, CHANG-EON
    • Transactions of the Korean hydrogen and new energy society
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    • v.32 no.6
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    • pp.573-584
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    • 2021
  • Hydrogen is evaluated as one of the new energy sources that can overcome the limitations and pollution problems of conventional fossil fuels. Although hydrogen is CO2-free, attention is required in NOx emission and flame stability in order to use hydrogen in existing gas fuel system. However, use of electric grids is an unrealistic strategy for decarbonization for residential and commercial heating. Instead, use of H2 that utilizes city gas grid is suggested as a reasonable alternative in terms of compatibility with existing systems, economic feasibility, and accessibility. In this study, the thermal efficiency and NOx performance of the boiler according to the H2 mixture ratio and vapor humidified ratio are reviewed for a humidified NG-H2 boiler that vapor humidity to combustion air. Mixed fuel with H2 (20%) is almost similar to NG in terms of efficiency, flame temperature, and pollution performance. Thus, it is expected to be directly compatible with the existing NG system. If the exhaust temperature of the H2 boiler is lowered to around 60℃ at a humidified ratio of 15-20%, the NOx emission concentration can be suppressed to about 5-10 ppm. The level of efficiency reaches 87% of the rated load efficiency, which is equivalent to the highest grade achievable.

Production of D-sorbitol and L-sorbose from Jerusalem artichoke by Zymomonas mobilis and Gluconobacter sMboxpydans (Zymomonas mobilis와 Gluconobacter suboxydans를 이용한 돼지감자로부터 D-sorbitol 및 L-sorbose 생성에 관한 연구)

  • 전억한;김원극
    • KSBB Journal
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    • v.8 no.1
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    • pp.10-16
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    • 1993
  • The use of Jerusalem artichoke containing $\beta$-1, 2-fructose oligomer for the production of D-sorbitol and L-sorbose has been studied. The employment of inulinase(0.398%, v/v) for the hydrolysis of 40% (v/w) Jerusalem artichoke juice resulted in 36.7g/1 of glucose and 85.3g/1 of fructose at $50^{\circ}C$. These sugars were utilized as substrates for D-sorbitol and L-sorbose production. Coimmobilization of inulinase and permeabilized cells of Zymomonas mobilis in the mixture of chitin (5%, w/e) and x-carrageenan(4%, w/v) resulted in the production of 30.2g/1 of D-sorbitol by using inulin as a substrate. The process of L-sorbose production from D-sorbitol by Gluconobacter suboxydans was optimized with respect to the substrate concentration, level of dissolved oxygen and glucosic and concentration. Gluconlc acid produced by Zymomonas mobilis from glucose was found to inhibit Gluconobacter suboxtans in conversion of D-sorbitol to L-sorbose. In view of removing such inhibitory effect by gluconic acid, mutants were selected by the NTG (N-methyl-N'-N'-nitro-N-nitrosoguanidlne) treated method. Mutants selected by NTG mutagenesis showed no inhibitory effects of gluconic acrid against L-sorbone production when its concentration increased up to 100g/1. A mutant produced 40.1g/l of L-sorbose in the medium containing 100g/l D-sorbitol and 100g/l-gluconic acid. This result is consider able when compared with L-sorbose concentration (21.7g/1) obtained from the fermentation with wild type strain of Gluconobacter suboxnians.

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