• Tuberculosis and Respiratory Diseases
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• v.51 no.5
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• pp.426-436
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• 2001

Objective : This study was performed to determine the smoking status and its associated factors in military life among young Korean men to provide data for smoking prevention in military areas as a part of the health promotion program for soldiers. Methods : 1,033 infantrymen serving in 17 military units, which are located in suburbs of K city, were enrolled in this study. A questionnaire on the soldiers smoking status and other various characteristics was obtained from October 2nd to 12th, 2000. Logistic regression analysis was performed on the various variables in order to determine the factors related to smoking. Results : 1) 830(80.3%) out of 1033 subjects had smoked cigarettes and 759 persons(73.4%) were regular smokers. 2) Among the 734 soldiers who started smoking before their military service, 714 soldiers(97.2%) continued to smoke after, while 45 soldiers(15.0%) among the 299 non-smokers started smoking after joining the army. 3) Through the logistic regression analysis. the education level. specialty in the army. smoking amongst the friends they met before military service, smoking amongst soldiers in the army. dating girl friends, drinking, satisfaction with their army lives and the presence of convenient smoking places at the barracks were significant factors related to the prevalence of smoking in soldiers. Conclusion : The factors related with incidence of smoking in the army are the complicated interactions among the individuals personal background, general characteristics of the soldier and the special environment in the barracks. Therefore, to improve national soldiers' health, an active non-smoking campaign and education should be pushed to discourage smoking in the barracks.

• Economic and Environmental Geology
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• v.54 no.6
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• pp.709-716
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• 2021

In this study, an adsorbent prepared by natural drying of iron hydroxide-based sludge collected from settling basin at a mine drainage treatment facility located in Gangneung, Gangwon-do was used to remove fluoride in an artificial fluoride solution and mine drainage, and the adsorption characteristics of the adsorbent were investigated. As a result of analyzing the chemical composition, mineralogical properties, and specific surface area of the adsorbent used in the experiment, iron oxide (Fe₂O₃) occupies 79.2 wt.% as the main constituent, and a peak related to calcite (CaCO₃) in the crystal structure analysis was analyzed. It was also identified that an irregular surface and a specific surface area of 216.78 m²·g^-1. In the indoor batch-type experiment, the effect of changes in reaction time, pH, initial fluoride concentration and temperature on the change in adsorption amount was analyzed. The adsorption of fluoride showed an adsorption amount of 3.85 mg·g^-1 16 hours after the start of the reaction, and the increase rate of the adsorption amount gradually decreased. Also, as the pH increased, the amount of fluoride adsorption decreased, and in particular, the amount of fluoride adsorption decreased rapidly around pH 5.5, the point of zero charge at which the surface charge of the adsorbent changes. Meanwhile, the results of the isotherm adsorption experiment were applied to the Langmuir and Freundlich isotherm adsorption models to infer the fluoride adsorption mechanism of the used adsorbent. To understand the thermodynamic properties of the adsorbent using the Van't Hoff equation, thermodynamic constants 𝚫H° and 𝚫G° were calculated using the adsorption amount information obtained by increasing the temperature from 25℃ to 65℃ to determine the adsorption characteristics of the adsorbent. Finally, the adsorbent was applied to the mine drainage having a fluoride concentration of about 12.8 mg·L^-1, and the fluoride removal rate was about 50%.