• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.3
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• pp.201-205
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• 2010

Most of iodine was captured by the block when NaI solution flowed through a bentonite block sorbed silver to retard the migration of iodine released from high-level radioactive wastes. In order to understand in detail the mechanism for the retardation of the iodine by the silver ion, X-ray Absorption Near Edge Structure (XANES) and Extended X-ray Absorption Fine Structure (EXAFS) spectra of the silver sorbed bentonite before and after the contact with iodide were compared with those of AgO, $Ag_2O$ and AgI as references. This examination suggests that the silver ion sorbed on the bentonite is desorbed, and then it retards the migration of iodine by forming the cluster of AgI precipitate.

• Journal of Convergence for Information Technology
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• v.10 no.10
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• pp.80-87
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• 2020

The purpose of this study was to compare in antiseptic effect between povidone-iodine and chlorhexidine-ethanol for laparoscopic cholecystectomy on the port site. A total of 46 patients admitted to surgery at one university hospital in Seoul were included in the study. A study group was randomly assigned using a random number table. The antiseptic effect was evaluated and compared to povidone-iodine and chlorhexidine-ethanol by using a culture and identification of bacteria, measurement of the number of bacteria (CFU/ml) and incidence of surgical site infection. Our results show that povidone-iodine and chlorhexidine-ethanol have no statistically significant difference in the incidence rate of bacteria after 3 minutes of disinfection and before removal of the trocar and in the number of bacteria and the incidence of surgical site infection. Thus, in order to select an efficient and appropriate skin antiseptics, we suggest that it is necessary to consider not only the disinfectant effect but also cost and convenience. In this research, our results about effect and usage of skin antiseptics can be used as basic data and educational resource, and this is expected to improve comprehension of skin antiseptics.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2012.05a
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• pp.245-246
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• 2012

• Transactions of the Korean hydrogen and new energy society
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• v.24 no.1
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• pp.61-69
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• 2013

Polymer exchange membrane (PEM) fuel cells have multifunctional properties, and bipolar plates are one of the key components in these fuel cells. Generally, a bipolar plate has a gas flow path for hydrogen and oxygen liberated at the anode and cathode, respectively. In this study, the influence of iodine applied to a bipolar plate was investigated. Accordingly, we compared bipolar plates with and without iodine coating, and the performances of these plates were evaluated under operating conditions of $75^{\circ}C$ and 100% relative humidity. The membrane and platinum-carbon layer were affected by the iodine-coated bipolar plate. Bipolar plates coated with iodine and a membrane-electrode assembly (MEA) were investigated by electron probe microanalyzer (EPMA) and energy-dispersive x-ray spectroscopy (EDS) analysis. Polarization curves showed that the performance of a coated bipolar plate is approximately 19% higher than that of a plate without coating. Moreover, electrochemical impedance spectroscopy (EIS) analysis revealed that charge transfer resistance and membrane resistance decreased with the influence of the iodine charge transfer complex for fuel cells on the performance.

• Korean Chemical Engineering Research
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• v.58 no.4
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• pp.635-641
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• 2020

In this study, phase equilibria and formation behaviors of methane hydrate containing mono-ethylene glycol (MEG) and salts (sodium chloride, NaCl; sodium bromide, NaBr; sodium iodide, NaI) are investigated. Equilibrium conditions of methane hydrate containing MEG and salts are measured in a temperature range 272~283 K and a pressure range 3.5~11 MPa. Hydrate inhibition performance in the presence of additives can be summarized as follows: methane hydrate containing (5 wt% NaCl + 10 wt% MEG) > (5 wt% NaBr + 10 wt% MEG) > (5 wt% NaI + 10 wt% MEG). Formation behaviors of methane hydrate with MEG and salts are investigated for analyzing the induction time, gas consumption amount and growth rate of methane hydrates. There are no significant changes in the induction time during methane hydrate formation, but the addition of MEG and salts solution during hydrate formation can affect the gas consumption amount and growth rate.

• Journal of Food Hygiene and Safety
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• v.29 no.3
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• pp.165-169
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• 2014

Salmonella spp. and Brucella spp. are associated with considerable diseases of both humans and animals. In addition, these microorganisms cause the economic loss in animal farming and food industry. In this study, the disinfection efficacy of a commercial disinfectant, composed to povidone-iodine was evaluated against S. typhimurium and B. ovis. A bactericidal efficacy test by broth dilution method was used to determine the lowest effective dilution of the disinfectant following exposure to test bacteria for 30 min at $4^{\circ}C$. The disinfectant and test bacteria were diluted with hard water (HW) or organic matter suspension (OM) according to treatment condition. On HW condition, the bactericidal activity of the disinfectant against S. typhimurium and B. ovis was 400 and 150 fold dilutions, respectively. On OM condition, the bactericidal activity of the disinfectant was 5 and 20 fold dilutions against S. typhimurium and B. ovis, respectively. As the disinfectant composed to povidine-iodine possesses bactericidal efficacy against animal pathogenic bacteria such as S. typhimurium and B. ovis, the disinfectant solution can be used to control the spread of bacterial diseases.

• Analytical Science and Technology
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• v.26 no.4
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• pp.235-244
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• 2013

Detection of halogens using laser-induced breakdown spectroscopy (LIBS) in open air is very difficult since their strong atomic emission lines are located in VUV region. In NIR region, there are other emission lines of halogens through electronic transitions between excited states. However, these lines undergo Stark broadening severely. We report the observation of the emission lines of halogens in laser-induced plasma (LIP) spectra in NIR region using a helium gas flow. Particularly, the emission lines of iodine at 804.374 and 905.833 nm from LIPs have been observed for the first time. In the helium ambient gas, Stark broadening of the emission lines and background continuum emission could be suppressed significantly. Variations of the line intensity, plasma temperature, and electron density with the helium flow rate was investigated. Detection of chlorine and bromine in flame retardant of rubbers was demonstrated using this method. Finally, we suggest a pulsed helium gas jet as a practical and ecomonical helium gas source for the LIBS analysis of halogens in open air.

• Analytical Science and Technology
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• v.28 no.1
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• pp.40-46
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• 2015

Hydrochar has been generated from food waste via hydrothermal carbonization (HTC) reaction. As a solid product of HTC reaction, hydrochar has a great potential as an adsorbent of pollutants from the various media. The surface area and pore volumes are very important parameters to be served as an adsorbent. It requires an expensive equipment and consumes time to measure those parameter. Therefore, titration methods including iodine and methylene blue adsorption were evaluated to be correlated with that of BET analysis. Even though the absolute values of the computed surface area and pore volumes were not able to be matched directly, the patterns of change were successfully correlated. Among the reaction conditions, the reaction time and temperature at $230^{\circ}C$ for 4 h was determined as an optimization condition, which confirmed by titration method and BET analysis. Titration method for surface area and pore volumes computed by combination of iodine and methylene blue adsorbing values would be a simple and fast way of determining the optimization condition for hydrochar as an adsorbent produced by HTC reaction.

• The Journal of the Acoustical Society of Korea
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• v.36 no.3
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• pp.172-178
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• 2017

Ultrasound has been widely used for biological and medical applications including induction of cell death, but a precise mechanism of induced cell death by ultrasound is controversial. In this study, an irradiation system with 40 kHz ultrasound was developed for a suitable cell death test of a representative unicellular organism, yeast, and used to study the biological effect of ultrasound on inducing cell death. Potassium Iodide (KI) dosimetry was used to devise an optimal system that successfully delivers 40 kHz ultrasound and produces reactive oxygen species in a 1.5 ml Eppendorf tube. Cell death was observed in an ultrasound transmission time-dependent fashion in this system. Thermal effect during irradiation was not observable in ultrasound induced cell death. Co-treatment of 40 kHz ultrasound and hydrogen peroxide showed a synergistic effect in inducing cell death. This finding suggests that 40 kHz ultrasound is related to reactive oxygen species formation. However, NAC (N-acetyl-L-cysteine) oxygen scavenger slightly inhibited the cell death by 40 kHz ultrasound. It was also found that 40 kHz ultrasound induced cell death was slightly inhibited by inhibitors of necrosis or apoptosis (glycyrrhizin or zVAD-fmk). This study suggests that cell death induced by 40 kHz ultrasound may not be exclusively related to reactive oxygen species formation and thermal effects in irradiated yeast cells.

• Pediatric Infection and Vaccine
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• v.25 no.1
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• pp.17-25
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• 2018

Purpose: Blood culture is an essential diagnostic tool and requires clear indications, proper techniques, and quality control. We aimed to investigate whether blood cultures in children are appropriate for indications, are performed correctly, and receive proper quality control. Methods: We conducted an online survey targeting pediatric infectious diseases (ID) specialists working in general hospitals and neonatologists (Neo) working at hospitals operating a neonatal intensive care unit in Korea. Results: Approximately 81.1% (30/37) of pediatric ID specialists and 72.2% (52/72) of Neo responded to the survey. Some of the respondents (33.3% of ID and 59.6% of Neo) performed blood culture as a regular test irrespective of the indication. Approximately 40% of ID and 65.4% of Neo ordered only one set of blood culture in patients suspected with bacteremia. The most commonly used disinfectant for skin preparation was povidone-iodine, while the skin preparation method varied by institution. Approximately two-thirds of the institutions were monitoring the blood culture contamination rate, whereas relatively few provided staff with feedback on that rate. In addition, less than half of the institutions were providing regular staff training on blood culture (40% of ID and 28.8% of Neo). Conclusions: The indication and methods of blood culture for children varied according to institution, and few hospitals exert effort in improving the quality of blood culture. Institutions have to strive constantly toward improvement of blood culture quality and evidence-based recommendations for pediatric blood cultures should be standardized.