• Journal of the Korean Geotechnical Society
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• v.32 no.5
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• pp.49-55
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• 2016

This study aims to present the practical Nitrogen monoxide (NO) removal capacity of cement mortar with Titanium dioxide ($TiO_2$) which is one of the paving materials by considering the environment of pavement in urban areas. NO removal capacity test under designated conditions of humidity of inflow gas and the test with variation of the degree of saturation of specimen were conducted. In the test for humidity, dry specimen is subject to the test and NO removal ratio was observed. Humidity-NO removal ratio curve is a log normal distribution in shape, and the maximum NO removal ratio appears at specific humidity. NO removal capacity test relying on the degree of saturation was carried out with wet specimen to reflect the unsaturated pavement by rainfall and domestic sewage. Wet specimen presents less NO removal capacity than dry specimen and the recovering evolution of NO removal capacity follows evaporation. Moreover, $TiO_2$ under the specific depth of specimen hardly contributes to NO removal capacity.

• Clean Technology
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• v.17 no.2
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• pp.142-149
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• 2011

The adsorption and desorption behaviors of NO and $N_2O$ over two mixed oxide catalysts, AlCoPd (1/1/0.05) and AlCoFe (1/1/2), have been investigated for the lean $NO_x$ trap applications. The catalysts showed good adsorption capabilities for NO and $N_2O$ without needing oxidation step. The adsorption decreased a lot when they are co-adsorbed with oxygen. While NO kept high adsorbability and selectivity with respect to oxygen, those of $N_2O$ decreased sharply. From the TPD results, NO and $N_2O$ are considered to decompose into nitrogen and oxygen in the higher temperature range and the oxygen seems to be strongly attached to the catalysts even at high temperature.

• Journal of the Korean Society of Safety
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• v.15 no.2
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• pp.92-96
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• 2000

In this experiment, we studied about concentration characteristics of $NO_x$ and generation of ozone in the reactor of corona discharge type by using mixed gas of $NO/N_2$ and $N_2/O_2$. In the case of the initial NO concentration increased, decrease rate of NO concentration was weakened and discharge input power of minimum NO concentration became high. When NO concentration was high, NO decomposition limit was appeared. And NO reduction rate was decreased, when initial NO concentration and discharge input power increased. When discharge input power was 5W, we could know the most proper energy value for treatment of NO. When the concentration of initial NO increased, generation of ozone decreased and in the case of same concentration of NO, according to discharge input power increase, generation of ozone increased.

• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.4
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• pp.266-272
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• 2018

In this study, we created grassland establishment(paddock No.39), grassland improvement(Paddock No.44), and tall fescue seeding(paddock No.64), and the rate botanical composition, DM yield, nutritive value were examined through 2016 to 2017. The rate of botanical composition was 81% in 2016, 75% in 2017, up to 21% higher than No.39 67%, 60%, No.44 58% and 54%. The annual average DM yield was the highest at 13,234kg/ha in the district, followed by No.39, No.44, followed by 10,636kg/ha and 10,235kg/ha, respectively. The crude protein content was the highest at No.39 12.16%, with No.44 and No.64 showing 10.7%, respectively. NDF content (average for two years) was 55.90% in No.44 and No.39, slightly lower than 58.42% and 57.00%, respectively. The two-year ADF average content was 31.07% for the same trend as the NDF capacity in the No.44, below 31.71% and 32.65%, respectively. To sum up the results, Although there was a high level of incentive sowing plot(No.39) in nutritive value, considering the botanical composition and productivity of the pasture, it is also deemed desirable to have a tall fescue plot(No.64).

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.1
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• pp.20-27
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• 2012

The $NH_3$-SCR characteristics of $NO_X$ over a V-based catalyst are experimentally examined over a wide range of operating conditions, i.e., $170-590^{\circ}C$ and $30,000-50,000h^{-1}$, with a simulated diesel exhaust containing $NH_3$, NO, $NO_2$, $O_2$, $H_2O$, and $N_2$. The influences of the space velocity and oxygen concentration on the standard-SCR reaction are analyzed, and it is shown that the low space velocity and high oxygen concentration promote the SCR activity by ammonia. The best $deNO_X$ efficiency is obtained with a $NO_2/NO_X$ ratio of 0.5 because of an enhanced chemical activity induced by the fast-SCR reaction, while at the $NO_2/NO_X$ ratios above 0.5 the $deNO_x$ activity decreases due to the slow-SCR reaction. The oxidation of ammonia begins to take place at about $300^{\circ}C$ and the reaction products, such as $N_2$, NO, $NO_2$, $N_2O$, and $H_2O$, are produced by the undesirable oxidation reactions of ammonia, particularly at high temperatures above $450^{\circ}C$. Also, $NO_2$ decomposes to NO and $O_2$ at temperatures above $240^{\circ}C$. Therefore, $NO_2$ decomposition and ammonia oxidation reactions deteriorate significantly the SCR catalytic activity at high temperatures.

• Journal of the Korean Society of Safety
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• v.10 no.2
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• pp.105-112
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• 1995

The concentrations of $NO_2$ were measured to estimate a new developed long term exposure $NO_2$ sampler at Pusan City considering the meteorological factors from May to July, in 1994. The monthly mean concentration of $NO_2$ was 15.9 PPb and 36.2 ${\mu}\ell$/day $NO_2$ and their high values were shown in the downtown of Pusan City which show potential pollution due to the increase of traffic activities and micrometeorological factors In and around the City. As a result of statistical correlation between $NO_2$ concentration by new sampling method and $NO_2$ concentration by the handy air sampler and chemiluminescent nitrogen oxides analyzer, 1994, correlation coefficients were high(r=0.93) and showed more than 0.88 value in the high concentration data set, which was arbitrarily divided into 30${\mu}\ell$ $NO_2$ concentration in an attempt to further investigate these relationships. Therefore, use of new developed long term exposure $NO_2$ sampler is good for $NO_2$ measurement and valuable for estimation of air quality in the urban and Industrial area.

• Journal of Environmental Health Sciences
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• v.21 no.1
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• pp.39-46
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• 1995

This study was carried out to investigate antibacterial activities of the green tea extract according to storage temperature as death velocity constant. The survey data were collected from seven green teas (2 Korean, 2 Japanese, 2 Chinease and 1 Vietnamese) and experimental strains were used E. coli No. 11234, Ent. aerogenes No. 11783, Ps. fiu. orescens No. 11210, S. marscens No. 11808, St. mutans No. 11823 and V. parahaernolyticus No. 11965. The experimental results obtained were as follows: 1. Antibacterial activities of the green tea extracts according to the strains were strikingly difference. That is, those of the samples appeared to be conspicuous on [St. mutans No. 11823 (Range of death velocity constant a day after, at 20$\circ$C 4.85~5.22) and V. parahaemolyticus No. 11965 (4.70~6.00) while E. coli No. 11234 (0.59~-0.30) and Ent. aerogenes No. 11783 (0.24~-0.11)] were not so. 2. To storage temperature at 5$\circ$C than that at 20$\circ$C, antibacterial activities of the green tea extract on Ps. fluorescens No. 11210, S. marscens No. 11808, E. coli No. 11234, and Ent. aerogenes No. 11783 were sensitived but St. mutans No. 11823 and V. parahaemolyticus No. 11965 were not related to those. 3. Antibacterial activities to the strains were increased within two days.

• Journal of Environmental Health Sciences
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• v.26 no.4
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• pp.58-64
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• 2000

Indoor air quality tends to be the dominant contributor to personal exposure, because most people spend over 80% of their time indoors. In this study, indoor and outdoor NO$_2$ concentrations were measured and compared with simultaneously personal exposures of 21 university students in weekday and weekend. House characteristics and activity pattern were used to determine the impacts of these factors on personal exposure. Since university students spent most of their times in indoor, their NO$_2$ exposure was associated with indoor NO$_2$ level rather than outdoor NO$_2$ level both weekday and weekend in spite of different time activity. Using time-weighted average model, NO$_2$ exposures of university students were estimated by NO$_2$ measurements in indoor home, indoor school, and outdoor home levels. Estimated NO$_2$ personal exposures were significantly correlated with measured NO$_2$ personal exposures($r^2$=0.87). However, estimated personal NO$_2$ exposures by time-weighted average model were underestimated, comparing with the measured personal NO$_2$ exposure. Using multiple regression analysis, effect of personal NO$_2$ exposure for transportation was confirmed.

• Journal of the Korean Chemical Society
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• v.39 no.3
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• pp.191-197
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• 1995

The reactions of [${Mo(NO)_2Cl_2}_n$] with unidentate ligands in $CH_2Cl_2$ solvent afforded monomeric complexes [$Mo(NO)_2L_2Cl_2$]. $[Mo(NO)_2L_4](ClO_4)_2$ was obtained by reaction of unidentate with $[Mo(NO)_2L_2Cl_2]$ in aceton solvent. 4-Dimethylaminopyridine(dmap), pyridine(py), and isoquinoline(isoq) were used as coordinating ligands. These dinitrosylmolybdenum complexes are prepared and characterized by elemental analysis, $^1H$ NMR, infrared, and UV-Visible spectroscopy. The infrared spectra indicate that the NO groups occupy cis-positions of the octahedral.

• Journal of the Korean Institute of Gas
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• v.4 no.2 s.10
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• pp.1-6
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• 2000

In this experiment, we made the plasma reactor which adhere needle electrode in order to treat safely an NOx which was included in the gas. Also we experimently investigated characteristics of equipment and inspected efficiency. As a reaction gas, by using mixture gas of $NO/N_2$ and $N_2/O_2$, we setted up initial NO concentration and gas flow rate was set at 2 ${\iota}$/min. As a reaction characteristics of NOx, when discharge input power was high, NO concentration decreased and when the oxygen concentration increased, the NO decomposition was easy and decomposition energy efficiency was high. Also in case that NO concentration increased, NO decomposition energy efficiency was high but decomposition rate was low. The characteristics of ozone, when discharge input power was high, ozone increased and when $NO/N_2$ concentration increased, the ozone decreased.