• Asian Journal of Atmospheric Environment
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• v.2 no.2
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• pp.102-108
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• 2008

In China, energy and environmental problems are becoming serious owing to rapid economic development. Coal is the most problematic energy source because it causes indoor and outdoor air pollution, acid rain, and global warming. One type of clean coal technology that has been developed is the coal-biomass briquette (or bio-briquette, BB) technique. BBs, which are produced from pulverized coal, biomass (typically, agricultural waste), and a sulfur fixation agent (slaked lime, $Ca(OH)_2$) under high pressure without any binder, have a high sulfur-fixation effect. In addition, BB combustion ash, that is, the waste material, can be used as a neutralization agent for acidic soil because of its high alkalinity, which originates from the added slaked lime. In this study, we evaluated the suitability of alternative biomass sources, namely, aquatic plants, as a BB constituent from the perspective of their use as a source of energy. We selected three types of aquatic plants for use in BB preparation and compared the fuel, handling, and environmental characteristics of the new BBs with those of conventional BBs. Our results showed that air-dried aquatic plants had a higher calorific value, which was in proportion to their carbon content, than agricultural waste biomass; the compressive strength of the new BBs, which depends on the lignin content of the biomass, was high enough to bear long-range intracontinental transport in China; and the new BBs had the same emission control capacity as the conventional BBs.

• Economic and Environmental Geology
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• v.54 no.4
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• pp.409-425
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• 2021

Carbon dioxide has been known to be a typical greenhouse gas causing global warming, and a number of efforts have been proposed to reduce its concentration in the atmosphere. Among them, carbon dioxide capture and storage (CCS) has been taken into great account to accomplish the target reduction of carbon dioxide. In order to commercialize the CCS, its safety should be secured. In particular, if the stored carbon dioxide is leaked in the arable land, serious problems could come up in terms of crop growth. This study was conducted to investigate the effect of carbon dioxide leaked from storage sites on soil fertility. The leakage of carbon dioxide was simulated using the facility of its artificial injection into soils in the laboratory. Several soil chemical properties, such as pH, cation exchange capacity, electrical conductivity, the concentrations of exchangeable cations, nitrogen (N) (total-N, nitrate-N, and ammonia-N), phosphorus (P) (total-P and available-P), sulfur (S) (total-S and available-S), available-boron (B), and the contents of soil organic matter, were monitored as indicators of soil fertility during the period of artificial injection of carbon dioxide. Two kinds of soils, such as non-cultivated and cultivated soils, were compared in the artificial injection tests, and the latter included maize- and soybean-cultivated soils. The non-cultivated soil (NCS) was sandy soil of 42.6% porosity, the maize-cultivated soil (MCS) and soybean-cultivated soil (SCS) were loamy sand having 46.8% and 48.0% of porosities, respectively. The artificial injection facility had six columns: one was for the control without carbon dioxide injection, and the other five columns were used for the injections tests. Total injection periods for NCS and MCS/SCS were 60 and 70 days, respectively, and artificial rainfall events were simulated using one pore volume after the 12-day injection for the NCS and the 14-day injection for the MCS/SCS. After each rainfall event, the soil fertility indicators were measured for soil and leachate solution, and they were compared before and after the injection of carbon dioxide. The results indicate that the residual concentrations of exchangeable cations, total-N, total-P, the content of soil organic matter, and electrical conductivity were not likely to be affected by the injection of carbon dioxide. However, the residual concentrations of nitrate-N, ammonia-N, available-P, available-S, and available-B tended to decrease after the carbon dioxide injection, indicating that soil fertility might be reduced. Meanwhile, soil pH did not seem to be influenced due to the buffering capacity of soils, but it is speculated that a long-term leakage of carbon dioxide might bring about soil acidification.

• Journal of the Korean Chemical Society
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• v.42 no.6
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• pp.646-651
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• 1998

The molecular structure of sulfur compounds and the retention relationship are studied by gas chromatography. Analyzed sulfur compounds are, hydrogen sulfide, sulfur dioxide, carbon disulfide, ethyl mercaptan, dimethyl sulfide, iso-propyl mercaptan, normal propyl mercaptan, ethyl methyl sulfide, tert-butyl mercaptan, tetrahydrothiophene, thiophene, and 2-chlorothiophene. Multiple linear regression explains the retention relationship of molecular descriptors. In GC the temperature program is 30$^{\circ}C$ held for 10.5 min, and then increased to 150$^{\circ}C$ at a rate 15$^{\circ}C$/min. Predicted equation for relative retention time (RRT) using SAS program is as follows; $RRT=0.121bp+14.39dp-8.94dp^2+0.0741sqmw-35.78\; (N=8,\; R^2=0.989, \;Variance=0.175,\;F=66.21)$. RRTs are function of boiling point, the square root of molecular weight, molecular dipole moment, and boiling point effects mostly on RRT. The RRT is maximized at the molecular dipole moment of 0.805D, when using nonpolar columns. The planar and highly symmetric compounds are eluted slowly. The square, of correlation coefficient $(R^2)$ using SAS program, is 0.989, and the variance is 0.175 in training sets. For three sulfur compounds, the variance between observed RRTs and predicted RRTs is 0.432 in testing sets.

• Korean Journal of Environmental Agriculture
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• v.7 no.2
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• pp.130-135
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• 1988

The study was performed to evaluate the usefulness of windbreaks to reduce the effect of sulfur dioxide and hydrogen fluoride on the growth of rice plants. It was observed that various pollution indicators such as the ambient concentrations of sulfur oxide and fluoride, sulfur and fluorine contents found in leaves appear to be significantly reduced within 3 meters behind the break. In that region yield components seemed normal. It is, however, observed that the pollutional indicators appear to increase gradually back to the same level as they were on the upwind side of the break. As for the relationships between pollution indicators and yields and also yield components it was believed that pollutants found in leaves might serve as the most important indicators of pollutional damage to rice plant Cultivation in fields. There was high correlation between ambient concentrations and yield, and also yield components. More significantly, a better correlation seemed to exist between sulfur and fluorine contents observed in leaves and yield ; And between those contents and yield components.

• Fire Science and Engineering
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• v.30 no.2
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• pp.7-18
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• 2016

This study evaluated the toxicity of the burning gas from the synthetic wood products used in housings or warehouses. The combustion products of five materials, viz. impregnated laminated board, MDF, Douglas fir plywood, core plywood, and Lauan retardant, were analyzed using SEM, FTIR and a Cone Calorimeter. For the Lauan retardant, 256,965 ppm of carbon dioxide ($CO_2$) and 1,475 ppm of sulfur dioxide ($SO_2$) were measured, which are 2.5 times and 3.6 times as high as their lethal concentrations of 100,000 ppm and 400 ppm, respectively. For the impregnated laminated board, 1,569 ppm of nitrogen dioxide ($NO_2$) was measured, which is 6 times as high as its lethal concentration of 250 ppm. For MDF, 795 ppm of ammonia ($NH_3$) was measured, which is higher than its lethal concentration of 750 ppm. As a result, most internal-finishes generated toxic combustion products at levels higher than their lethal concentrations, which underlines the importance of the selection and manufacturing of internal-finish materials.

• Korean Chemical Engineering Research
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• v.47 no.4
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• pp.436-440
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• 2009

This study demonstrates the use of a chemical lung containing potassium superoxide to convert carbon dioxide in air to oxygen. In order to reduce its extremely high reactivity, potassium superoxide was first mixed with calcium hydroxide and then combined at various ratios with polysiloxane. Silicone polymer used here served as both a water repellent and the polymer matrix. In general, the amount of carbon dioxide captured as well as that of oxygen produced increased as the proportion of potassium superoxide in the chemical lung increased. FT-IR spectroscopy revealed that the Si-O bond in chemical lung appeared at $1,050cm^{-1}$ and absorbance of chemical lung containing higher amounts of silicone was higher than that of chemical lung containing lower amounts. These results indicate that such a chemical lung may also be a useful sorbent for other acid gases, such as sulfur oxides and nitrogen oxides.

• Journal of Preventive Medicine and Public Health
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• v.48 no.3
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• pp.151-169
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• 2015

Objectives: The deleterious effects of air pollution on various health outcomes have been demonstrated. However, few studies have examined the effects of air pollution on liver enzyme levels. Methods: Blood samples were drawn up to three times between 2008 and 2010 from 545 elderly individuals who regularly visited a community welfare center in Seoul, Korea. Data regarding ambient air pollutants (particulate matter ${\leq}2.5{\mu}m$ [$PM_{2.5}$], nitrogen dioxide [$NO_2$], ozone [$O_3$], carbon monoxide, and sulfur dioxide) from monitoring stations were used to estimate air pollution exposure. The effects of the air pollutants on the concentrations of three liver enzymes (aspartate aminotransferase [AST], alanine aminotransferase [ALT], and ${\gamma}$-glutamyltranspeptidase [${\gamma}$-GTP)]) were evaluated using generalized additive and linear mixed models. Results: Interquartile range increases in the concentrations of the pollutants showed significant associations of $PM_{2.5}$ with AST (3.0% increase, p=0.0052), ALT (3.2% increase, p=0.0313), and ${\gamma}$-GTP (5.0% increase, p=0.0051) levels; $NO_2$ with AST (3.5% increase, p=0.0060) and ALT (3.8% increase, p=0.0179) levels; and $O_3$ with ${\gamma}$-GTP (5.3% increase, p=0.0324) levels. Significant modification of these effects by exercise and alcohol consumption was found (p for interaction <0.05). The effects of air pollutants were greater in non-exercisers and heavy drinkers. Conclusions: Short-term exposure to air pollutants such as $PM_{2.5}$, $NO_2$, and $O_3$ is associated with increased liver enzyme levels in the elderly. These adverse effects can be reduced by exercising regularly and abstinence from alcohol.

• Journal of Environmental Health Sciences
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• v.24 no.2
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• pp.134-144
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• 1998

A comprehensive air quality monitoring was carried out to investigate the criteria concentration of air pollutant in indoor of subway stations of Seoul City. The samples were collected twice per year (the first and the second half of the year) at each sampling point from February to September in 1997. Sampling point of subway stations was ticket office and platform. The measurement of indoor air pollutants such as sulfur dioxide(SO$_2$), nitrogen dioxide(NO$_2$), carbon monoxide(CO), carbon dioxide(CO$_2$), total suspended particulate(TSP) was performed to determine the indoor air quality. Heavy metals(Pb, Cd, Cu, Cr, As, Hg) were also measured together with those air pollutants. The annual average concentration of CO$_2$ and TSP in subway stations were relatively high while those of heavy metals were within 10% of environmental recommended standard concentration in all stations. As results of regression analysis between line and line of air factors, the concentrations of CO, CO$_2$, TSP, Pb, Cd, Cr and Cu were highly correlated, but those of $SO_2, NO_2$ and Hg were not correlated. As results of regression analysis between ticket office and platform, the concentrations of heavy metals such as Cr and Cu were highly correlated. Results of oneway analysis of variance between the first and the second half of the year air factors also indicated that CO, CO$_2$, Cd, Cu, Hg were significant($\alpha$=0.01), respectively. The average contration of total suspended particulate(TSP) in subway line No. 1 was shown high concentration(200 $\mu g/m^3\cdot$ day) level.

• Journal of the Korean Data and Information Science Society
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• v.25 no.6
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• pp.1293-1300
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• 2014

The temperature data influences on various policies of the country. In this article, the autoregressive error (ARE) model has been considered for analyzing the monthly and seasonal temperature data at the northern part of the Chungcheong Namdo, Seosan monitoring site in Korea. In the ARE model, five meteorological variables, four greenhouse gas variables and five pollution variables are used as the explanatory variables for the temperature data set. The five meteorological variables are wind speed, rainfall, radiation, amount of cloud, and relative humidity. The four greenhouse gas variables are carbon dioxide ($CO_2$), methane ($CH_4$), nitrous oxide ($N_2O$), and chlorofluorocarbon ($CFC_{11}$). And the five air pollution explanatory variables are particulate matter ($PM_{10}$), sulfur dioxide ($SO_2$), nitrogen dioxide ($NO_2$), ozone ($O_3$), and carbon monoxide (CO). The result showed that the monthly ARE model explained about 39-63% for describing the temperature. However, the ARE model will be expected better when we add the more explanatory variables in the model.

• Journal of Preventive Medicine and Public Health
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• v.51 no.6
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• pp.265-274
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• 2018

Objectives: A positive association between air pollution and both the incidence and prevalence of diabetes mellitus (DM) has been reported in some epidemiologic and animal studies, but little research has evaluated the relationship between air pollution and diabetic coma. Diabetic coma is an acute complication of DM caused by diabetic ketoacidosis or hyperosmolar hyperglycemic state, which is characterized by extreme hyperglycemia accompanied by coma. We conducted a time-series study with a generalized additive model using a distributed-lag non-linear model to assess the association between ambient air pollution (particulate matter less than $10{\mu}m$ in aerodynamic diameter, nitrogen dioxide [$NO_2$], sulfur dioxide, carbon monoxide, and ozone) and emergency department (ED) visits for DM with coma in Seoul, Korea from 2005 to 2009. Methods: The ED data and medical records from the 3 years previous to each diabetic coma event were obtained from the Health Insurance Review and Assessment Service to examine the relationship with air pollutants. Results: Overall, the adjusted relative risks (RRs) for an interquartile range (IQR) increment of $NO_2$ was statistically significant at lag 1 (RR, 1.125; 95% confidence interval [CI], 1.039 to 1.219) in a single-lag model and both lag 0-1 (RR, 1.120; 95% CI, 1.028 to 1.219) and lag 0-3 (RR, 1.092; 95% CI, 1.005 to 1.186) in a cumulative-lag model. In a subgroup analysis, significant positive RRs were found for females for per-IQR increments of $NO_2$ at cumulative lag 0-3 (RR, 1.149; 95% CI, 1.022 to 1.291). Conclusions: The results of our study suggest that ambient air pollution, specifically $NO_2$, is associated with ED visits for diabetic coma.