• Korean Chemical Engineering Research
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• v.57 no.4
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• pp.475-483
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• 2019

Special chemical warfare agents are lethal gases that attack the human respiratory system. One of such gases are blood agents that react with the irons present in the electron transfer system of the human body. This reaction stops internal respiration and eventually causes death. The molecular sizes of these agents are smaller than the pores of an activated carbon, making chemical adsorption the only alternative method for removing them. In this study, we carried out a Computational Fluid Dynamics simulation by passing a blood agent: cyanogen chloride gas through an SG-1 gas mask canister developed by SG Safety Corporation. The adsorption bed consisted of a Silver-Zinc-Molybdenum-Triethylenediamine activated carbon impregnated with copper, silver, zinc and molybdenum ions. The kinetic analysis of the chemical adsorption was performed in accordance with the test procedure for the gas mask canister and was validated by the kinetic data obtained from experimental results. We predicted the dynamic behaviors of the main variables such as the pressure drop inside the canister and the amount of gas adsorbed by chemisorption. By using a granular packed bed instead of the Ergun equation that is used to model porous materials in Computational Fluid Dynamics, applicable results of the activated carbon were obtained. Dynamic simulations and flow analyses of the chemical adsorption with varying gas flow rates were also executed.

• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.444-450
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• 2022

The effect of coated polyester (PET) textiles with metal oxide, chitosan, and copper ion on the antibacterial and antiviral activities was evaluated to investigate the applicability of multi-coated PET textiles as antiviral materials. Compared to coated PETs with a single agent, multi-coated PETs reduced the loading amount of coating materials as well as the contact time with bacteria for a bacterial cell number of < 10 CFU/mL, which was not detectable with the naked eyes. Metal oxides generate reactive oxygen species (ROS) such as free radicals by a catalytic reaction, and copper ions can promote contact killing by the generation of ROS. Chitosan not only enhanced antibacterial activities due to amine groups, but enabled it to be a template to load copper ions. We observed that multi-coated PET textiles have both antibacterial activities for E. coli and S. aureus and antiviral efficiency of more than 99.9% for influenza A (H1N1) and SARS-CoV-2. The multi-coated PET textiles could also be prepared via a roll-to-roll coating process, which showed high antiviral efficacy, demonstrating its potential use in air filtration and antiviral products such as masks and personal protective equipment.

• Tuberculosis and Respiratory Diseases
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• v.46 no.1
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• pp.44-52
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• 1999

Background : Airway infiltration by inflammatory cells, particularly of eosinophils, is one of the characteristic features of asthma. Several mechanisms for the recruitment of eosinophil is focused on the CD4+ T lymphocyte for the preferential production of Th2-c1erived cytokines. Interleukin-10(IL-10) is identified cytokine with potent antiinflammatory activity. This molecule has been shown to inhibit the release of cytokine from inflammatory cells including Th2 cell, and also to inhibit eosinophil survival. We therefore attempted to determine whether decreased synthesis of IL-10 in the lung of bronchial asthma may contribute to inflammation that is characteristics of this dease. Method: Subjects were patients with bronchial asthma(n=23) and normal controls(n=11). IL-10 produced from peripheral mononuclear cell(PBMC) and in bronchoalveolar lavage(BAL) fluid was measured by ELISA method. Degree of bronchial inflammation was assessed by total cell counts and eosinophil percents in BAL fluid, eosinophil infiltration on bronchial biopsy tissue and $PC_{20}$ for methacholine. Results: The IL-10 level produced by PBMC and in BAL fluid from patient with bronchial asthma were not different with normal controls(respectively, $901.6\pm220.4$ pg/ml, $810.9\pm290.8$ pg/ml for PBMC, $24.5\pm9.5$ pg/mL $30.5\pm13.5$ pg/ml for BAL fluid p>0.05). There were significant negative correlation between IL-10 in BAL fluid and eosinophil percents in BAL fluid or degree of eosinophil infiltration in bronchial biopsy (respectively r=-0.522, r=-0.4486 p<0.05). However there was no difference of IL-10 level according to $PC_{20}$ for methacholine. There were no correlation between IL-10 production by PBMC and peripheral blood eosinophil counts or serum eosinophilic cationic protein levels(respectively r=0.1146, r=0.0769 p>0.05). Conclusion: These observation suggest that IL-10 may participate but not acts the crucial role in regulation of the airway inflammation in bronchial asthma.