• Journal of Radiation Protection and Research
• /
• v.23 no.1
• /
• pp.7-15
• /
• 1998

In order to evaluate the effectiveness of some decontamination agents against skin contamination of $^{60}Co$ and $^{137}Cs$, the experiments were carried out in this study. In the experiments, pig skin was used instead of human skin , $^{60}CoC1_2$ and $^{137}CsCl$ were used the liquid sources of skin contamination. To examine the effectiveness of decontamination agents, skin decontamination was tried using soup, EDTA, KAERICON which was developed for decontamination of radionulides on the surface of building structure, and new decontamination agents such as IOCON, TRICON, and CHARCON, which were developed in this study. The absorption of radionuclides through the skin was evaluated by the gamma-tay detection on the surface of sample skin after radionuclides were penetrated into the skin during 16 hour soiling time. The results of this absorption experiment indicated that 11.5% and 3.2% of initial amounts of $^{137}Cs$ and $^{60}Co$, respectively, were panerated into the skin. In the experiment to remove the residual radioactivity fixed on the skin, KAERICON showed the decontamination rates up to 52.1%(decontamination factor of 2.1) and IOCON showed the equivalent decontamination rate (decontamination factor 1.9) for $^{137}Cs$. However, IOCON and CHARCON showed the poor decontamination rates of less than 20%(decontamination factor of 1.2) for $^{60}Co$, and KAERICON showed the poor decontamination rate (decontamination factor 1.1) for $^{60}Co$. For TRICON, the decontamination factors were 1.6 to 1.8 for $^{137}Cs$, and 1.0 to 1.2 for $^{60}Co$, respectively.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.11 no.2
• /
• pp.101-108
• /
• 2008

This study attempted to develop the technology by gaseous ozone for decontaminating building affected by a model of biological weapon agent(Bacillus subtilis spores) instead of Bacillus anthracis spore. The use of ozone is attractive method from a practical point of view of decontamination procedure since it has strong oxidation power but no residue after application. We examined the disinfection efficiency of gaseous ozone to Bacillus subtilis spores which suspension was sprayed on different material surfaces and dried. Three different types of gaseous ozone was applied : dry ozone, dry ozone with humidified air, and water bubbled wet ozone. Dry ozone(1500ppm) failed to achieve any significant inactivation for 2hrs. However, six log reduction of B. subtilis spore was achieved within 30min by 1500ppm of water bubbled wet ozone. This result shows the noticeable inactivation efficiency by gaseous ozone compared with previous studies. Good performance by wet ozone was also found for military material surface.(i.e. : gas mask hood, protective garments, army peinted metal surface).

• Journal of The Korean Society of Clinical Toxicology
• /
• v.16 no.1
• /
• pp.15-24
• /
• 2018

Purpose: This study was conducted to analyze the factors associated with intoxicated patient's disposition in the pediatric emergency department. Methods: We retrospectively evaluated pediatric intoxicated patients visiting the pediatric emergency department of a hospital between January 1, 2011 and December 31, 2013. Specifically, we analyzed the association between hospitalization recommended rate and the following variables: patient age group, symptoms, intentional poisoning, decontamination and toxic level of substance. Results: We collected data from 345 patients. A high incidence was noted in the 1-4 years of age group and 10-15 years of age group. Unintentional poisoning occurred in 306 patients (88.7%). A total of 115 patients (33.3%) had symptoms when visiting. Forty three patients (12.5%) ingested cleaning substances, which was the most common agent. Potentially-toxic level was the most common level of the substance. The hospitalization recommended rate associated with visits in 2011 was 2.5 times greater than in 2012 and 2013, decontamination was 2.0 times greater than no decontamination, and poisoning with potentially-toxic substances was 2.6 times greater than poisoning with other toxic substances. Additionally, the hospitalization recommended rate associated with symptomatic patients was 2.4 times greater than that of asymptomatic patients and intentional poisoning was 2.4 times greater than unintentional poisoning. Conclusion: Patients with decontamination, ingestion of potentially-toxic substances, symptoms and intentional poisoning had increased hospitalization rates. In addition, the hospitalization rate for patients who visited in 2011 was greater than that of patients who visited in 2012 or 2013.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.7 no.4
• /
• pp.295-301
• /
• 2019

Currently, the most commonly used decontamination agent in the country is calcium chloride, and the use of decontamination agents nationwide is on the rise due to climate change in the country. The deicing agent, aimed at deicing snow, is sprayed and the chloride is frozen and thawed by the dissolved surface water, causing various damages such as deterioration to the concrete. Therefore, in this study, the reactive urethane polymer was manufactured to coat concrete surface protection material, which is a method that prevents moisture from externally penetrating by applying to concrete surfaces, and the mixing agent was selected through the size control of molecules and surface modification, and the properties of penetrant stiffening agents and the application method of concrete was evaluated.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.8 no.2
• /
• pp.91-97
• /
• 2010

As nuclear power plants are getting older, interests on a decontaminating process are increasingly attracting more attention. Chemical decontamination is crucial to lower the production of radioactive waste and radiation dose rate. Prior to this, oxidizers and detergents for target material should be chosen so as to decontaminate major systems and components of a nuclear power plant chemically. In order to decontaminate it properly, it is crucial to have information about the chemical composition and crystalline structure of CRUD, analyzing its samples from the target or the decontamination system with components. However, there is no program which enables the extraction of samples directly from the object or the decontamination system with components carrying genuine radioactivity. Therefore, it is limited to samples from corrosion products carrying partial radioactivity as a resource. The composition of CRUD varies considerably depending on refueling cycle because it is closely related to the constituent of basic material. After settling a target, it is crucial to analyze and obtain analytical information about CRUD as a decontamination target. In this paper, various technologies for manufacturing simulated CRUD are introduced as alternatives to unattained samples. A metal oxide or metal hydroxide was used to synthesize simulated cruds having chemical compositions and crystalline stricture similar to the actual one by 12 different methods. CRUD 4(metal oxides in the autoclave vessel) and CRUD 10(metal oxides in a crucible after hydrazing pretreatment)were chosen as the best method for Type 1 and Type 2.respectively. As these CRUD can be synthesized easily without using any specialized equipment or reagents in a short time and in large quantities, they are expected to stimulate the development of decontaminating agents and processes.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.12 no.3
• /
• pp.199-209
• /
• 2014

Crevice corrosion tests were conducted to examine the corrosion properties of HYBRID (HYdrazine Base Reductive metal Ion Decontamination) which was developed to decontaminate the PWR primary coolant system. To compare the corrosion properties of HYBRID with commonly existing decontamination agents, oxalic acid (OA) and citric oxalic acid (CITROX) were also examined. Type 304 Stainless Steel (304 SS) and Alloy 600 which are major components of the primary coolant system in Pressurized Water Reactor (PWR) were evaluated. Crevice corrosion tests were conducted under very aggressive conditions to confirm quickly the corrosion properties of primary coolant system structure components which have high corrosion resistance. Pitting and IGA were occurred in crevice surface under OA and CITROX conditions. But localized corrosion was not observed under HYBRID condition. Very low corrosion rate of less than $1.3{\times}10^{-3}{\mu}m/h$ was observed under HYBRID condition for both materials. On the other hand, under OA condition, Alloy 600 indicated comparatively uniform corrosion rate of $4.0{\times}10^{-2}{\mu}m/h$ but 304 SS indicated rapid accelerated corrosion in lower case than pH 2.0. In case of HYBRID condition, general corrosion and crevice corrosion were scarcely occurred. Therefore, material integrity of HYBRID in decontamination of primary coolant system in pressurized water reactor (PWR) reactor was conformed.

• Nuclear Engineering and Technology
• /
• v.53 no.8
• /
• pp.2761-2766
• /
• 2021

A method for preparing "reagent" for radioactive methyliodide vapors production using an isotopic exchange reaction has been developed. Based on the obtained data of the isotopic exchange efficiency and hydraulic resistance, white fused alumina (700-840 ㎛) was selected as the carrying agent material for "reagent" production. The radioiodine isotopic exchange dependences on such parameters as temperature, gas flow velocity, and the methyliodide concentration in it were determined. Optimal conditions have been selected to achieve 85% of the isotopic exchange rate in 1 h of the experiment. The obtained data allowed to develop an approach to the test of iodine filters for nuclear power plants and to determine their efficiency.

• Textile Coloration and Finishing
• /
• v.32 no.2
• /
• pp.96-102
• /
• 2020

Recently, it was reported that chitosan or APTMS(3-aminopropyltrimethoxysila ne) treatment to cotton using the simple pad-dry-cure method has potential to prepare textile materials for military chemical warfare protective clothing. However, it is not confirmed which method is more efficient. Therefore, this study aims to quantitatively compare detoxification properties of chitosan treated cotton fabric with those of APTMS treated cotton fabric. Detoxification properties were evaluated using the well-known organic phosphorous nerve agent stimulant, diisopropylfluorophosphate(DF P). With the same amount of chitosan and APTMS on the surface of the cotton fabrics, APTMS treated cotton fabric exhibited 10% higher detoxification properties than chitosan treated cotton fabric based on the rate of DFP hydrolysis and half-live of DFP calculated from the DFP decontamination ratios of the treated cotton fabrics through time. Therefore, APTMS treatment can be more efficient method to prepare the textile materials for military protective clothing than chitosan treatment.

• Journal of Soil and Groundwater Environment
• /
• v.26 no.1
• /
• pp.54-64
• /
• 2021

The chemical warfare agents (CWAs) have been developed for offensive or defensive purposes and used as chemical weapons in war and terrorism. The CWAs are exposed to the natural environment, transported through the water system and then eventually contaminate soil and groundwater. Therefore, effective decontamination technology to remediate CWAs are needed. The CWAs are extremely dangerous and prodution is strictly prohibited, therefore, it is difficult to use CWAs even in experimental purpose. In this study, 2,4-dichlorophenoxyacetic acid (2,4-D) was chosen as a model representative CWA because it is a simulant of anti-plant CWAs and one of the major component of agent orange. The optimum degradation conditions such as oxidant:activator ratio were determined. The effects of hydroxylamine and chelating agents such as citric acid (CA), oxalic acid (OA), malic acid (MA), and EDTA addition to increase Fe2+ activation were also investigated. Scavenger experiments using tert-butyl alcohol (TBA) and ethanol confirmed that although both sulfate (SO4•-) and hydroxyl radical (•OH) existed in Fe2+-persulfate system, sulfate radical was the predominant radical. To promote the Fe2+ activator effect, the effect of hydroxylamine as a reducing agent was investigated. In chelating agents assisted Fe2+-persulfate oxidation, the addition of 2 mM of CA and MA enhanced 2,4-D degradation. In contrast, EDTA and OA inhibited the 2,4-D removal due to steric hindrance effect.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.33 no.3
• /
• pp.500-504
• /
• 2004

This study was designed to investigate the possible utilization of Zanthoxylum schinifolium as a source of decontamination agents. The antimicrobial effect of Zanthoxylum schinifolium extract was investigated against Vibrio parahaemolyticus which is food-born disease organism. Ethanol extract of Zanthoxylum schinifolium was compared with water extract of Zanthoxylum schinifolium to test antimicrobial activities against Vibrio parahaemolyticus by disk method. Ethanol extract was more effective than water ,extract on the antimicrobial activities. It had remarkable antimicrobial activities against Vibrio parahaemolyticus. It was very stable on the wide range of temperature and pH. It turned out by GC-MS that estragole (4-allyl anisole) was a major antimicrobial component of Zanthoxylum schinifolium extract. These results indicated that Zanthoxylum schinifolium extract could protect against bacterial contamination and inhibit a growth of Vibrio parahaemolyticus.