• Journal of Radiation Protection and Research
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• v.48 no.1
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• pp.20-27
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• 2023

Background: As the number of nuclear facilities nearing their pre-determined design life increases, demand is increasing for technology and infrastructure related to the decommissioning and decontamination (D&D) process. It is necessary to consider the nature of the dismantling environment constantly changing and the worker doing new tasks. A method was studied that can calculate the effect of learning and the change in work time on the work process, according to the learning-forgetting curve model (LFCM). Materials and Methods: The LFCM was analyzed, and input values and scenarios were analyzed for substitution into the D&D process of a nuclear facility. Results and Discussion: The effectiveness and efficiency of the training were analyzed. It was calculated that skilled workers can receive a 16.9% less collective radiation dose than workers with only basic training. Conclusion: Using these research methods and models, it was possible to calculate the change in the efficiency of workers performing new tasks in the D&D process and the corresponding reduction in the work time and collective dose.

• Membrane Journal
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• v.27 no.1
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• pp.104-107
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• 2017

Among many methods in solving the organic contamination in the reverse osmosis operation, caustic soda (NaOH) wash method is efficient and commercially affordable. In continuation of our many organic pollution removal works, this study focused mainly on caustic soda wash with micro-bubble to removal the organic contamination of the spent membrane from reverse osmosis process. First, the membrane was forced the pollute using known organic pollutants such as Humic acid, Bovine serum albumin, Sodium alginate drug. The organic contamination on the membrane was monitored flux. The decontamination of organic contaminants was derived flux variation at individual caustic soda was injected micro-bubble methods and combined method as well. the found results explain removal of organic contaminants effective only by combined caustic soda wash with micro-bubble methods.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.3
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• pp.291-301
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• 2015

Product regulations specify requirements or constraints for products that manufacturers must comply with across the entire product lifecycle, from design and manufacture, through operation and maintenance, to recycling and disposal. This paper suggests a system framework and its essential components for the verification of a pressure vessel design using the industrial standards of Korea. The authors also present methods to generate design template data from legacy design systems and to construct a regulation knowledge base. The proposed framework is demonstrated through experiments involving pressure vessel design verification using a prototype system.

• Journal of Dairy Science and Biotechnology
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• v.31 no.2
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• pp.179-186
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• 2013

Pseudomonas spp. are Gram-negative psychrophilic bacteria, which can proliferate at refrigeration temperature. The bacteria produce heat-stable enzymes that can degrade fat and protein in foods. Hence, Pseudomonas spp. are related to the spoilage of milk, dairy products, and meat products under cold storage, causing economic loss. In the food industry, various methods have been used to remove bacteria including Pseudomonas spp. in food-related conditions, but they can be resistant to antimicrobials and sanitizers because they form biofilms regulated by quorum sensing (cell density-dependent cell-to-cell signaling). Since Pseudomonas cells in biofilms can cross-contaminate foods resulting in food spoilage and the survival of food-borne pathogens in food-related conditions, efficient decontamination technology and microbiological criteria should be established to reduce the occurrence of food spoilage by Pseudomonas spp.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.650-654
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• 2003

A major problem of nuclear energy is the production of radioactive wastes. Needs for more environmentally favorable method to decontaminate radioactive contaminants make the use of liqui $d^ercritical $CO_2$ as a solvent medium. In removing radioactive metallic contaminants under $CO_2$ solvent, two methods - use of chelating ligands and that of water in $CO_2$ emulsion-are possible. In the chelating ligand method, a combination of ligands that can make synergistic effects seems important. We discuss about the properties of microemulsion formed by F-AOT and that by non-ionic surfactant. By adding acid in water core, decontamination of metallic parts, soils were possible. The rate of metal surface dissolution to the microemulsion solution was measured by QCM. The possibility of recovering the surfactants after use is also mentioned.ed.

• Journal of Food Hygiene and Safety
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• v.5 no.1
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• pp.1-6
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• 1990

Extraction properties were investigated on ginseng leaf tea as functions of the current ethylene oxide fumigation and gamma irradiation at 2.5 to 10 kGy. In the extraction of tea constituents at boiling conditions, water soluble matters were the highest (83% yield for 5 min) in the time dependence, followed by tannin (82%), sugar (73%) and saponin (66%). No significant difference was observed in the extraction yield between the 5 kGy-irradiated and control samples, whereas both EO fumigation and 10 kGy irradiation reduced the extraction time of soluble matter and tannin, leading to the decrease in Hunter L value of tea extracts.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.11
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• pp.745-750
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• 2010

Since the implementation of the LMO Law in Korea, the importance of the design qualification of BSL3 lab. is emphasizing. In this study, multizone simulation for three kind of biohazard scenarios using CONTAM is performed for design qualification of BSL3 lab. Also, in the case of unexpected spread of contaminants such as Influenza A virus(H1N1) in BL3 zone, the design qualification is carried out for diffusion and decontamination of contaminants according to differential pressure of BSL3 anteroom and door area of BSL3 lab. Also, in this study, appropriateness of laboratory room differential pressure and air flow rate to maintain pressure difference between laboratory rooms, and energy consumption due to air change rate variation according to door area in BL3 lab. Simulation results show that these approach methods are used as a tool for the design and verification of BL3 lab.

• Journal of Microbiology and Biotechnology
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• v.18 no.7
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• pp.1207-1215
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• 2008

To investigate the occurrence and species diversity of mycobacteria in waters, surface water samples were collected monthly from the Han River and tap water samples at the terminal sites of the distribution system. Mycobacteria in each water sample were isolated by decontamination using cetylpyridinium chloride (CPC) and cultivation on Middlebrook 7H10 agar, and then identified by polymerase chain reaction-restriction fragment length polymorphism analysis (PRA) and sequencing of the 65-kDa heat-shock protein gene (hsp65 gene). Mycobacteria were detected in 59% of the surface water samples and 26% of the tap water samples. Over half of the 158 isolates could not be identified by hsp65 PRA and gene sequencing, and several identification discrepancies were observed between the two methods. The most frequently isolated species was Mycobacterium gordonae in surface water and M. lentiflavum in tap water. M. avium complex (MAC), the most important pathogen among environmental mycobacteria, was detected in the surface water samples but not found in the tap water samples. The result demonstrated that water is an important environmental source of mycobacteria and the combined application of hsp65 PRA and sequencing was more reliable than hsp65 PRA alone to accurately identify mycobacteria present in water.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.2 no.1
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• pp.43-50
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• 2016

$^{89}Zr$ with the favorable nuclear decay kinetics and chemical properties is an appealing radiometal for its application in immuno-PET using radiolabeled monoclonal antibodies. Rising demand of ultrahigh purity and high-specific activity $^{89}Zr$ has propelled the radiochemist worldwide to develop an overall efficacious method for its promising separation from the target matrix $^{89}Y$. The requirement of elevated radiochemical purity (${\geq}$ 99.99%) has accelerated the efforts since last two decades to achieve higher decontamination and separation factors of carrier free $^{89}Zr$ over $^{89}Y$ using several suitable separation techniques. However, each of the technique has its own pros and cons which prior to its actual medical application needs to be optimized and thoroughly scrutinized to avoid further complications during radiolabelling of the pharmaceuticals. In this short review article we will specifically consider as well focus on the historical development and the recent advances on the radiochemical separation of $^{89}Zr$ from $^{89}Y$ which will be helpful for the separation scientist involved in this area to understand the existing available means and plan the strategy to investigate and develop the novel techniques to overcome the problems involved in the present methods.

• Microbiology and Biotechnology Letters
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• v.51 no.4
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• pp.374-389
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• 2023

Organophosphorus (OP) pesticides, particularly malathion, parathion, diazinon, and chlorpyrifos, are widely used in both agricultural and residential contexts. This refractory quality is shared by certain organ phosphorus insecticides, and it may have unintended consequences for certain non-target soil species. Bioremediation cleans organic and inorganic contaminants using microbes and plants. Organophosphate-hydrolyzing enzymes can transform pesticide residues into non-hazardous byproducts and are increasingly being considered viable solutions to the problem of decontamination. When coupled with system analysis, the multi-omics technique produces important data for functional validation and genetic manipulation, both of which may be used to boost the efficiency of bioremediation systems. RNA-guided nucleases and RNA-guided base editors include zinc-finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and clustered regularly interspaced short palindromic repeats (CRISPR), which are used to alter genes and edit genomes. The review sheds light on key knowledge gaps and suggests approaches to pesticide cleanup using a variety of microbe-assisted methods. Researches, ecologists, and decision-makers can all benefit from having a better understanding of the usefulness and application of systems biology and gene editing in bioremediation evaluations.