• Journal of Korean Society for Atmospheric Environment
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• v.5 no.1
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• pp.22-32
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• 1989

In order to assess the level of atmospheric pollution and to contribute the health improve ment of residents in Pusan, the authors measured the $CO, SO_2, NO_2, TSP, Noise, Pb, Cd, Cr and V$ level at 3 place by time from Jan. 1988 to Feb. 1988. THe places were Kukje, Daehyeon, Pujeon underground commercial floor. The results were as follows; 1. The range of concentration of air pollutants (1) CO : 0.5 - 3.0 ppm (2) $SO_2$ : 0.012 - 0.360 ppm (3) $NO_2$ : 0.018 - 0.089 ppm (4) TSP : 30 - 330 $\mug/m^3$ (5) Pb : 0.219 - 3.116 $\mug/m^3$ (6) Cd : 0.000 - 0.070 $\mug/m^3$ (7) Cr : 0.378 - 4.098 $\mug/m^3$ (8) V : 0.000 - 1.010 $\mug/m^3$ (9) Noise : 47 - 77 dB(A) 2. The level of all air pollutants were higher in the afternoon or night than in the morning. 3. The mean concentration of $SO_2$ in all places exceede the ambient air quality standard of $SO_2$,.

• Environmental Engineering Research
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• v.24 no.3
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• pp.389-396
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• 2019

The electrical energy consumption (EEC) in removal of NO by a $UV/H_2O_2$ oxidation process was introduced and related to removal efficiency of this gas. The absorption-reaction of NO was conducted in a bubble column reactor in the presence of $SO_2$. The variation in NO removal efficiency was investigated for various process parameters including NO and $SO_2$ inlet concentrations, initial concentration of $H_2O_2$ solution and gas flow rate. EEC values were obtained in these different conditions. The removal efficiency was increased from about 22% to 54.7% when $H_2O_2$ concentration increased from 0.1 to 1.5 M, while EEC decreased by about 70%. However, further increase in $H_2O_2$ concentration, from 1.5 to 2, had no significant effect on NO absorption and EEC. An increase in NO inlet concentration, from 200 to 500 ppm, decreased its removal efficiency by about 10%. However, EEC increased from $2.9{\times}10^{-2}$ to $3.9{\times}10^{-2}kWh/m^3$. Results also revealed that the presence of $SO_2$ had negative effect on NO removal percentage and EEC values. Some experiments were conducted to investigate the effect of $H_2O_2$ solution pH. The changing of pH of oxidation-absorption medium in the ranges between 3 to 10, had positive and negative effects on removal efficiency depending on pH value.

• Journal of Integrative Natural Science
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• v.11 no.1
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• pp.30-38
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• 2018

CALPUFF is one of the recommended air pollution models by EPA with AERMOD. It has been used to simulate the ambient concentration of critical air pollutants as well as non-critical pollutants such as persistent organic matters and the organic materials causing odor. In this model, the air pollutants go through dispersion, transportation, chemical reaction, and deposition process. These mechanisms are significantly influenced by meteorological condition. This study produces the meteorological field in three different methods for the simulation of $SO_2$ using CALPUFF: 1) CALMET model by using both ground-level and aerological observation, 2) CALMET model by using MM5 results with NCEP/NCAR reanalyzed data, 3) CALMET model by using MM5 results in which FDDA is applied with NCEP/NCAR reanalyzed data as well as the meteorological data of Korea Meteorological Administration. As a result of CALPUFF model, the resolved concentration of $SO_2$ showed different behaviors in three cases. For the first case, the fluctuation of SO2 concentration was frequently observed while the fluctuation is reduced in the second and third cases. In addition, the maximum concentration of $SO_2$ in the first case was about 2~3 times higher than the second case, and about 4~6 times higher than the third case. These results can be caused by the accuracy of the resolved meteorological field. It is inferred that the meteorological field of the first case could be less accurate than other two cases. These results show that the use of correct meteorological data can improve the result of dispersion model. Moreover, the contribution of various sources such as point, line, and area sources on the ambient concentration of air pollutant can be roughly estimated from the sensitivity analysis.

• Journal of Environmental Science International
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• v.7 no.4
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• pp.505-510
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• 1998

This study has been carried out to investigate Electrostatic Precipitator's(ESP) performance enhancement and removal efficiency of fine particle according to (NH4)2SO4injection rate. The following conclusions are derived from the these test results : 1) For plant condition cases, according to the variation of concentration agent [(NH4)2SO4]-10ppm, when inlet dust loading was 2g/m2. And when Inlet dust loading was 3g/m", that was increased to 98 19% 99.16% 99.23%, 99.58%, 2) It Is seen from thins experiments that the increasing 30ppm concentration of (NH4)2SO4 increase the collection efficiency and fine particle omission control.

• Korean Chemical Engineering Research
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• v.47 no.4
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• pp.512-517
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• 2009

$SO_2$ concentrations in oxy-fuel combustion flue gases increases about three times as high as that of conventional air combustion system owing to the flue gas recirculation for the control of combustion temperature. So the desulfurization reaction is different from that of the conventional air combustion system due to exceptionally high $CO_2$ and $SO_2$ concentration. In this study, drop tube furnace(DTF) system was used to investigate the desulfurization characteristics of limestone in oxy-fuel combustion furnace. The experiments were performed under $O_2/CO_2$ atmosphere to examine the effect of operating variables such as reaction temperatures, Ca/S ratios and inlet $SO_2$ concentrations on the $SO_2$ removal efficiencies. $SO_2$ removal efficiency increased with reaction temperature, Ca/S ratio and inlet $SO_2$ concentration. And the addition of water vapor resulted in about 4~6% of increase in $SO_2$ removal efficiency.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.6
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• pp.420-425
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• 2011

In general, the decomposition of $CaSO_4$ formed by sulfation reaction in the in-furnace desulfurization process using limestone has strong effect on the desulfurization reaction under the oxy-fuel combustion condition. In this study, the conversion rates were measured and reaction rates were calculated in order to investigate the effects of the experimental variables such as temperature and the concentrations of $CO_2$, $O_2$, $SO_2$, on the $CaSO_4$ decomposition reaction using DTF (Drop Tube Furnace) in the desulfurization reaction. The conversion rate and the reaction rate of $CaSO_4$ decomposition reaction were increased with reaction temperature. $CO_2$ concentration has little effect on $CaSO_4$ decomposition reaction in the presence of $O_2$. Under the same experimental conditions, the decomposition rate of $CaSO_4$ was enhanced with the decreasing the $O_2$ concentration, but vice versa with the increasing of $SO_2$ concentration.

• Journal of Electrochemical Science and Technology
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• v.13 no.2
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• pp.292-307
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• 2022

The study presents kinetics of degradation and mineralization of an anti-epileptic drug Lamotrigine (LAM) in the aqueous matrix by electrochemical advanced oxidation process (EAOP) on Ti/DSA (Ta₂O₅-Ir₂O₅) and Stainless Steel (SS) anodes using sodium sulphate as supporting electrolyte. On both the anodes, kinetic behaviour was pseudo-first-order for degradation as well as mineralization of LAM. On Ti/DSA anode, maximum LAM degradation of 75.42% was observed at an associated specific charge of 3.1 (Ah/litre) at a current density of 1.38 mA/cm² and 100 ppm Na₂SO₄ concentration. Maximum mineralization attained was 44.83% at an associated specific charge of 3.1 (Ah/litre) at a current density of 1.38 mA/cm² and 50 ppm concentration of Na₂SO₄ with energy consumption of 2942.71 kWh/kgTOC. Under identical conditions on SS anode, a maximum of 98.92% LAM degradation was marked after a specific charge (Q) of 3.1 (Ah/litre) at a current density of 1.38 mA/cm² and 100 ppm concentration of Na₂SO₄. Maximum LAM mineralization on SS anode was 98.53%, marked at a specific charge of 3.1 (Ah/litre) at a current density of 1.38 mA/cm² and 75 ppm concentration of Na₂SO₄, with energy consumption of 1312.17 kWh/kgTOC. Higher Mineralization Current Efficiency (MCE) values were attained for EAOP on SS anode for both degradation and mineralization due to occurrence of combined electro-oxidation and electro-coagulation process in comparison to EAOP on Ti/DSA anode due to occurrence of lone electro-oxidation process.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.2
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• pp.225-233
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• 2008

Accoring to the worldwide interest to control CO$_2$ which contributes to global warming 50%, new techniques to reduce CO$_2$ are under development. Therefore, this study investigated that CO$_2$ absorption/regeneration of Sodium-based dry sorbent and the effect of SO$_2$ concentration in the fixed bed reactor. The dry sorbents were prepared in the condition of different PVA contents and calcination temperatures. As the results of this study, BET surface area showed 832.79 m$^2$/g and SEM result showed possibility as dry sorbent due to having of much micropore distribution. Also, the fixed bed reactor showed decreased CO$_2$ absorption capacity with SO$_2$ injection, because of the generation of $Na_2SO_3$ and $Na_2SO_4$.

• Applied Biological Chemistry
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• v.24 no.2
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• pp.105-111
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• 1981

Growth responses of Brevibadterium ammoniagenes BA 17-2, which had been obtained by the treatment of several mutagens in our previous report, were investigated to select the preliminary optimal concentrations of phosphate, $Mg^{++}$, $Mn^{++}$ and thiamine for the production of 5'-XMP aminase. In this experiment it was shown that the concentration of phosphate in the medium has an important effect on the growth of microorganism. Using the medium containing 0.2% of $MgSO_4{\cdot}7H_2O$, 3mg/l of $MnSO_4{\cdot}H_2O$and $1\;mg/l$ of thiamine-HCl, the maximum cell mass was obtained at the concentration of 0.4% of $KH_2PO_4$ and $K_2HPO_4$, respectively. Above the concentration of these phosphates, cell growth was inhibited as the phosphate concentration increased to 1%, but the inhibition was overcome by the addition of 1% of $MgSO_4{\cdot}7H_2O$ and 3mg/l of thiamine-HCl. The 5'-XMP aminase activity was also influenced by the concentration of phosphate, $Mg^{++}$, $Mn^{++}$, and thiamine. In addition, the optimal culture pH and temperature for the enzyme activity were found to be 6.8 and $32^{\circ}C$, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.8
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• pp.1179-1189
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• 2006

This experiment was designed to examine the effects of supplemental vitamin D on laying performance, metabolic profile and egg quality of hens fed diets containing different fat sources and levels. Lohman strains (n = 480) were assigned to one of 10 diets: basal diet (BD), BD plus 2.5 and 5.0% sunflower oil (SO) or tallow (T) at vitamin D provided $1{\times}$ and $3{\times}$ of the current recommendation. The experiment lasted from week 30 to 44 of age. Each diet was tested in 12 replicate cages of 4 hens. Production, metabolism, and egg quality data were subjected to three-way ANOVA. Both fats decreased feed intake (FI) as compared to BD. Increasing SO and T levels linearly decreased and quadratically increased FI, respectively. The dietary factors did not affect egg production (EP) and egg weight. Vitamin D supplementation increased and decreased EP when diets contained SO and T, respectively. Feed conversion efficiency (FCE) for hens fed SO was lower than for hens fed T. However, increasing T level improved FCE, whereas increasing SO level worsened FCR. Vitamin D supplementation increased serum vitamin D and glucose concentrations. Vitamin D supplementation also caused a decrease and an increase in serum vitamin D concentration when diets contained SO and T, respectively. Serum glucose concentration for hens fed SO was lower than hens fed T. Increasing fat level linearly increased serum triglyceride and VLDL concentrations, regardless of the fat type. Increasing SO level linearly decreased serum cholesterol concentration. Vitamin D supplementation did not alter lipid metabolites. The dietary factors did not affect serum total protein, Ca, and P concentrations. As compared with BD, feeding SO decreased dry tibia and ash weights more than feeding T. Vitamin D supplementation tended to increase dry tibia weight and decrease tibia ash weight. Eggshell strength and thickness, yolk and albumen indexes, and Haugh unit were not responsive to the dietary factors. Eggshell strength quadratically increased with increasing T level. Yolk color for hens fed SO was lower than for hens fed T. The dietary factors did not affect most of yolk fatty acids. Increasing SO level quadratically decreased yolk $C_{18:2}$ concentration. Vitamin D supplementation increased and decreased yolk $C_{18:2}$ concentration when diets contained SO and T, respectively. In conclusion, increasing fat level improved laying performance without altering metabolic profile and egg quality. Vitamin D supplementation had minor alteration effects on laying performance, metabolic profile, and egg quality in response to fat feeding.