• Korean journal of applied entomology
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• v.36 no.3
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• pp.264-269
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• 1997

Four strains of Bacillus thuringiensis were isolated froin the dead larvae of mulberry longicorn beetle (Apriong germari) and dung beetle (Aphodius apicalis). One nf four B. thuringiensis isolates turned out to be subspecies darinstadiensis but the remains were not identified using 33 B. thuringiensts flgellar ( H ) antibodies. Furthermore. bioassays of spore-parasporal inclusion protein mixture conducted against third instar larvae of A. gerrntrri or A. apicalis, second instar larvae of Bombyx mori, and third instar larvae of Cu1ex pipiens pullens showed that the isolates were non-toxic. To further confirm, four isolates were characterized and analysed by SDS-PAGE and agarose gel electrophoresis. The results revealed that parasporal protein and plasmid DNA patterns of four isolates are different from those of darmstadiensis and 20 known non-toxic B. thuringiensis strains, suggesting that the four isolates are novel non-toxic B. thuringiensis.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.987-995
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• 2013

The purpose of this study is to examine the hydraulic stability of non-toxic revetment technique for eco-friendly design of the domestic river restoration. Recently, instead of the flood control function-oriented river management policy for the engineering efficiency, the improvement of the environmental performance for the ecological river restoration project is implemented. However, the inappropriate hydraulic design criteria of the new revetment technique happen to the economic losses at flood season frequently. The hydraulic stability of the riprap and the block include the banks of rivers, riverbed protection, scour protection and so on. In this study, the high speed experimental channel was developed, which has the maximum velocity of 3.5 m/s, to perform the hydraulic experiments of the block method with non-toxic glue with various conditions to find the critical velocity of the revetment block for the hydraulic stability.

• Journal of Environmental Policy
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• v.3 no.2
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• pp.113-137
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• 2004

The objective of this study is to introduce the definitions and classification methods of wastes in international agreements and legislations, examine the concept of wastes and their classification systems in Korea, and finally analyze and compare the concept of wastes in different countries for finding better solutions and suggestions. The study summarizes the concept of wastes as introduced in the Basel Convention, OECD, EU, US, and UK. First, each of the member countries adapt to the same concepts of wastes as defined in their international agreements; second, the intention of the wastes holder and the conditions of the wastes are considered at the same time when defining the concepts. Upon close examination of the classification of wastes systems as introduced in the Basel Convention, OECD, EU, US, and UK, the wastes are classified into toxic and non-toxic wastes according to the existence of poisonous substances. Therefore, it is classified as a toxic waste when any toxic substance on its list is included in the waste, while others are considered as a non-toxic waste if they don't contain poisonous substances. Secondly, in the UK, the matter of toxic or non-toxic wastes are classified, not according to the existence of the poisonous substances, but based on the generation of sources. In Korea, the concepts of wastes are divided into the two categories - a concept as defined in actual legislations and a concept in its translation. The Korean classification of the wastes include Wastes Management Act, amended in 1995, which stipulates that toxic substances should be managed in a special way as the designated wastes. It appears that the Act utilizes the classification method that classifies the wastes according to the existence of poisonous substance. Korea's concepts of wastes should be changed after recognition of the concepts in international agreement (Basel Convention, EU) and other foreign laws(US, UK) that consider subjective and objective standards at the same time when they define the concepts. Also, the development of technology in recycling and reuse of the wastes can remove the current absolute notion of the wastes so that it also should not be passed over. Also, because a classification structure of wastes has a close relationship with a disposal structure, its classification system should be fixed gradually to come up with the development of wastes disposal technology and its policy.

• Journal of Korea Soil Environment Society
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• v.2 no.1
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• pp.3-12
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• 1997

Phytoremediation, using plants to remediate toxic organic and inorganic pollutants in contaminated soils, is an emerging technology for environmental cleanup. Three strategies of this technology are applicable to the remediation of toxic heavy metals, radionuclides, and toxic organic pollutants: They are (1) phytoextraction, in which plants anumulate the contaminants and are harvested for the downstream processing; (2) phytodegradation, in which plant-released enzymes or plant-associated microorganisms convert toxic pollutants into non-toxic materials; and (3) phytostabilization, in which toxic pollutants are precipitated from solution or absorbed in either the plant tissue or the soil matrix. Phytoremediation is more effective and less expensive than other current treatment technologies.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.102-106
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• 2003

The uptake of $^{14}C$-2, 4, 6-trinitrotoluene (TNT) in hydroponics was studied using onion plants. Of the total TNT mass (5 $\mu\textrm{M}$ concentration), 75% was in the roots, 4.4% in the leaves, and 21% in the external solution at 2 days, The percent distribution in roots was lower with higher concentration in the external solution, but in leaves it was comparable at all concentrations (5-500 $\mu\textrm{M}$). Root concentration factor (RCF) in hydroponics was more than 85 in constant hydroponic experiment (CHE) at 5 $\mu\textrm{M}$ and 150 in non-constant hydroponic experiment (NHE) at 5 $\mu\textrm{M}$. The maximum RCF values in the hydroponic system were greater with lower solution concentration. Transpiration stream concentration factor (TSCF) values in the present study (NHE only: 0.31-0.56) were relatively similar to the values with predicted values (0.43-0.78), increasing with higher external TNT concentration. For phytotoxicity tested in hydroponics and wet paper method, 500 $\mu\textrm{M}$ was toxic to onion plant, 50 $\mu\textrm{M}$ was non-toxic for plant growth but limited the transpiration rate, and 5 $\mu\textrm{M}$ was non-toxic as control.

• Molecular & Cellular Toxicology
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• v.1 no.4
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• pp.268-274
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• 2005

Bromobenzene (BB) is well known hepatotoxicant. Also, BB is an industrial solvent that arouses toxicity predominantly in the liver where it causes centrilobular necrosis. BB is subjected to Cytochrome P450 mediated epoxidation followed by either conjugation with glutathione, enzymatic hydrolysis or further oxidation. In this study, we focused on BB-induced gene expression at non-hepatotoxic dose. Mice were exposed to two levels of BB, sampled at 24 h, and hepatic gene expression levels were determined to evaluate dose dependent changes. When examining the toxic dose of BB treated group in other previous studies, genes related to heat shock protein, oxidative stress, and drug metabolism are expressed. Compared to these results, our study, in which non-toxic dose of BB was administrated, showed similar patterns as the toxic conditions above. The purpose of the study was to select genes that showed changes in relation to the differing dose through confirmation of the difference within transcriptomic boundaries, but those that are not detected by the existing classic toxicology tools in non-hepatotoxic dose.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.65-65
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• 2012

Copper zinc tin sulfide ($Cu_2ZnSnS_4$, CZTS) is a very promising material as a low cost absorber alternative to other chalcopyrite-type semiconductors based on Ga or In because of the abundant and economical elements. In addition, CZTS has a band-gap energy of 1.4~1.5eV and large absorption coefficient over ${\sim}10^4cm^{-1}$, which is similar to those of $Cu(In,Ga)Se_2$(CIGS) regarded as one of the most successful absorber materials for high efficient solar cell. Most previous works on the fabrication of CZTS thin films were based on the vacuum deposition such as thermal evaporation and RF magnetron sputtering. Although the vacuum deposition has been widely adopted, it is quite expensive and complicated. In this regard, the solution processes such as sol-gel method, nanocrystal dispersion and hybrid slurry method have been developed for easy and cost-effective fabrication of CZTS film. Among these methods, the hybrid slurry method is favorable to make high crystalline and dense absorber layer. However, this method has the demerit using the toxic and explosive hydrazine solvent, which has severe limitation for common use. With these considerations, it is highly desirable to develop a robust, easily scalable and relatively safe solution-based process for the fabrication of a high quality CZTS absorber layer. Here, we demonstrate the fabrication of a high quality CZTS absorber layer with a thickness of 1.5~2.0 ${\mu}m$ and micrometer-scaled grains using two different non-vacuum approaches. The first solution-processing approach includes air-stable non-toxic solvent-based inks in which the commercially available precursor nanoparticles are dispersed in ethanol. Our readily achievable air-stable precursor ink, without the involvement of complex particle synthesis, high toxic solvents, or organic additives, facilitates a convenient method to fabricate a high quality CZTS absorber layer with uniform surface composition and across the film depth when annealed at $530^{\circ}C$. The conversion efficiency and fill factor for the non-toxic ink based solar cells are 5.14% and 52.8%, respectively. The other method is based on the nanocrystal dispersions that are a key ingredient in the deposition of thermally annealed absorber layers. We report a facile synthetic method to produce phase-pure CZTS nanocrystals capped with less toxic and more easily removable ligands. The resulting CZTS nanoparticle dispersion enables us to fabricate uniform, crack-free absorber layer onto Mo-coated soda-lime glass at $500^{\circ}C$, which exhibits a robust and reproducible photovoltaic response. Our simple and less-toxic approach for the fabrication of CZTS layer, reported here, will be the first step in realizing the low-cost solution-processed CZTS solar cell with high efficiency.

• Journal of Food Hygiene and Safety
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• v.32 no.3
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• pp.217-221
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• 2017

The ptaquiloside is a carcinogenic compound from bracken fern (Pteridium aquilinum L). This study was to evaluate the content of ptaquiloside in bracken fern by various processing methods. The processing methods were heated and immersed time, water exchange number, and so on. Akali hydrolysis and solvent fractionation of ptaquiloside in bracken fern leads to the non-toxic and chemically stable pterosin B. The contents of pterosin B was analyzed by UPLC-MS/MS on mobile phase 3 mM ammonium acetate and methanol. The contents of total pterosin B in non-processing bracken fern in water extraction was 81.0 mg/kg and toxic ptaquiloside of them was 46.4 mg/kg. The heating time of 5 minutes removed 60% about the contents of pterosin B in the bracken fern, and two-thirds of them were already non-toxic pterosin B, namely were not transfered from ptaquiloside. Additional immersed time (12h), the pterosin B in bracken fern was 10 mg/kg, it was removed 87.6% and once every hour, water exchange times were removed 99.5% in comparison with them of untreated bracken fern and two-thirds of them were non-toxic pterosin B. To remove of ptaquiloside in bracken fern, heat, immersion, and water exchange times shall be carried out simultaneously.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.3
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• pp.467-480
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• 1999

Many antinutritional and toxic factors abound in tropical seeds, which are also generally rich in nutrients and therefore more prone to attack from herbivores. Antinutritional and toxic factors are considered to defend seeds against environmental vagaries and thus help to protect them. These factors though good for the plant, cause deleterious effects or are even toxic to animals and man. The conventional seeds cultivated for oil or non-oil purposes, and general aspects of antinutritional factors are not presented here as these have already been discussed widely by many workers. Deficits in conventional protein and energy sources in the tropics have stimulated a quest for alternative feeds both for animals and humans. This article attempts to highlight two new oilseed crops, Jatropha curcas and Moringa oleifera, and in addition deals with some under-utilized seeds with potential as animal feed. Most of these seed plants are adapted to various marginal growing conditions in the tropics and can help to mitigate the prevailing deficit in protein and energy sources. Antinutritional and toxic factors in seed or seed meal, various approaches to detoxify seed meal, and future research and development priorities for their exploitation as animal feeds are presented.

• The Korean Journal of Emergency Medical Services
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• v.24 no.3
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• pp.117-128
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• 2020

Purpose: This study analyzed the information and accessibility of toxic substances provided to Internet websites. Methods: From August 1, 2020, to August 31, 2020, we analyzed eight internet websites regarding toxic pharmaceuticals, pesticides, and chemicals. The website-evaluation criteria were divided into five categories for information and five categories for website convenience. Results: All eight websites about toxic substances were hosted by reliable institutions or organizations and provided accurate information in terms of informational relevance. The website run by the Safety and Health Corporation scored the highest with 100points. Analysis of the websites' accessibility to non-members' revealed that six (75.0%) were accessible, but two (12.5%) provided only limited information. Access to information through mobile apps was only available in three of the eight cases (37.5%). Conclusion: This study can be used as a reference for Internet websites about toxic substances. Toxicological information that can be viewed only with membership and manager approval requires membership in advance of viewing. In addition, emergency medical personnel working at a site or hospital should be familiar with the characteristics of toxicity information retrieval.