• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.58-61
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• 2002

An alternative to pump and treat groundwater remediation is the use of reactive barriers. Zero valent iron (ZVI) is particularly useful as a reductant of chlorinated hydrocarbons because of its low cost and lack of toxicity ZVI can drive the dechlorination of chlorinated organic compounds and the reduction of chromium from the Cr(Ⅵ) to the Cr(III) state. The contaminants in subsurface environment usually exist as the mixed compounds. Therefore, the objective of this research is to study the effect of the other compounds on TCE removal by ZVI. The removal mechanism of TCE by ZVI is separated the dechlorination and sorption. TCE removal by ZVI slightly increased in presence of naphthalene as the non-reduced compound. TCE removal by ZVI remarkable decreased in presence of carbon tetrachloride, nitrate, and chromate as the reduced compounds. This research suggests that the effect of the coexisted compounds on the removal chlorinated compounds by reactive barrier technology should be considered for practical application.

• 한국환경과학회지
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• 제4권3호
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• pp.259-267
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• 1995

This study was conducted to evaluate the effects of pressure and dissolved oxygen concentration on the activated slut비e and to determine the optimum depth of deep shaft process. Some results from this study were summarized as follows. 1. It is considered that low sludge product in the activated sludge system maintaining high dissolved oxygen concentration is attributed to the increase of endogeneous respiration rate caused by the increase of aerobic zone in the sludge floe. 2. The increase of dissolved oxygen concentration does not affect to the increase of organic removal efficiency greatly and therefore the limiting factor is the substrate transfer into the inner part of floe. 3. The yield coefficient, Y is decreased in proportion to the increase of oxygen concentration. In this study, Y values arre ranged from 0.70 to 0.41 according to the variation of dissolved oxygen concentration from 18.0mg/$\ell$ to 258 mg/$\ell$. 4. The optimum depth of deep shaft process should be determined within the limits of non-toxicity to the microorganism and it is about loom in this study.

• 한국전기전자재료학회논문지
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• 제27권6호
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• pp.399-406
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• 2014

Thermal batteries are used for military power sources that require robustness and long storage life such as missiles and torpedoes. $FeS_2$ powder is currently used for cathode materials because of its high specific energy density, environmental non-toxicity and low cost. However, large particle size of conventional $FeS_2$ has been deterred its possible application for higher power thermal batteries. In order to improve the power density, high energy ball milling of $FeS_2$ has been introduced to crush the micron-sized $FeS_2$. Discharge characteristics of the single cells fabricated with nano-materials and conventional $FeS_2$ powder were evaluated.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.347.4-348
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• 2002

Recently it has been demonstrated that selective cyclooxygenase-2 (COX-2) inhibitors retain the antiinflammatory effect but with markedly reduced GI toxicity compared to non selective inhibitors such as traditional NSAIDs. As a consequence, intense efforts have been made to develop selective COX-2 inhibtors during the last decade. Two compounds in this class. celecoxib and rofecoxib. are already in the market and are proved as potent and selective COX-2 inhibitors with much better gastric tolerance. However. there are still strong domands for a COX-2 inhibitor with improved efficacy and safety profiles. Here we report the synthesis and biological profiles of 1.5- and 4.5-disubstituted imidazole analogues as structural equivalents of cefecoxib and refecoxib. The imidazole analogues are overlapped well whth the 3D srructures of celecoxib and rofecoxib.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.178-178
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• 2006

Chitosan has been investigated as a non-viral vector because it has several advantages such as biocompatibility, biodegradability and low toxicity with high cationic potential. However, low specificity and low transfection efficiency of chitosan as a DNA carrier need to be overcome for clinical trials. In this study, chemical modification for enhancement of cell specificity and transfection efficiency was investigated. Also, the chitosan derivative formulations in vivo were included.

• 한국잡초학회지
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• 제13권4호
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• pp.195-202
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• 1993

The benefits of pesticides in improving the food quantity and quality requirements for an increasing world population are significant, and they can be described in agronomic, economic and social terms. The risks are assessed from the hazards which are likely to occur in practice ; the hazards are defined by the toxicity of the pesticide to non-target organisms at various exposure levels. There are ways of reducing the risks (mainly by reducing exposure in practice) and improving the benefits of pesticides ; these are known as risk management and benefit management respectively. The overall risk-benefit assessment is facilitated if each component can be expressed in financial terms, but it must be made nationally or locally on a sound technical basis against the prevailing agronomic, socio-economic and political circumstances. Paraquat is used to illustrate the risk-benefit assessment process in general terms, and the conclusion is that the benefits greatly outweigh the risks. It is important to keep the risks of pesticides in perspective with those associated with other naturally occurring chemicals in our diet and with other everyday aspects of life. In an overall context, the pesticide risk is small.

• Bulletin of the Korean Chemical Society
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• 제35권11호
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• pp.3195-3198
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• 2014

An ultra-sensitive detection method for small molecules such as antibiotics was developed using ICP-MS with magnetic and $TiO_2$ nanoparticles. Since most of the antibiotics are too small to employ a sandwich-type extraction through an immunoreaction, a non-specific platform was employed, in which the target was extracted by magnetic separation, followed by tagging with $TiO_2$ nanoparticles of 11.2 nm for ICP-MS measurement. The detection limit for salinomycin obtained from spiked serum samples was $0.4ag\;mL^{-1}$ (${\pm}10.3%$), which was about $1.5{\times}10^6$ times lower than that of LC-MS/MS and about $1.2{\times}10^{11}$ times better than that of ELISA. Such an excellent sensitivity enabled us to study the toxicity of antibiotics exposed to human beings by determining them in serum.

• KSBB Journal
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• 제14권6호
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• pp.747-753
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• 1999

Microbial surfactants are more effective and environmentally friendly than many synthetic surfactants. Sophorolipid, a glycolipid type microbial surfactant, is produced from C. bombiocola. Cultivation techniques to increase the productivity have been developed using various carbon sources and reactor setup, reaching its concentration upto 100-300 g/L. Due to its high productivity and non-toxicity, sophorolipid became one of the most promising alternative to synthetic surfactants. Fermentative production of sophorolipid depends primarily on the carbon sources, such as glucose and vegetable oils, and nitrogen sources. Chemical modification of the sophorolipid produces various derivative with different physical properties including hydrophile-liphophilie balance(HLB), emulsion formation, surface tension and dispersing ability. Commercial potentials of sophorolipid in the cosmetic, health care and environment clean-up industries have been discussed.

• Toxicological Research
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• 제19권1호
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• pp.73-82
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• 2003

To evaluate influence of Saposhnikovia divaricata (Turcz.) Schischk extract on rat, Saposhnikovia divaricata (Turcz.) Schischk extract was diluted with 0.9% saline (100 mg/ml/kg, 10 mg/ml/kg, and 1 mg/ml/kg, respectively), and each of diluted test material extract was daily treated subcutaneously for 4 weeks and single-treated subcutaneously for 2 weeks. There were no significances in body weight analysis, urinary analysis, and ophthalmological test. However, in serum biochemical analysis and hematological analysis, we found some significances in high and middle dose group compared with control group. These significances in serum biochemical analysis and hematological analysis may be not induced by test material, because it was not found to be significant from control group in histopathological examination. Therefore, it was concluded that NOEL (No Observed Effect Level) of test material extract may be higher than all treatment doses used in this study, and Saposhnikovia divaricata (Turcz.) Schischk extract may be a non-toxic material.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1998년도 Proceedings of International symposium on Recent Technology of Chemical Control of Plant Diseases
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• pp.50-69
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• 1998

Dimethomorph is a novel fungicide with a high level of activity against diseases induced by certain Oomycetes, including fungal populations that are resistant to other products. In several ways, this fungicide illustrates the opportunities and challenges presented by many modern pesticides. The specific mode of action, which affects cell wall formation, is associated with a very high level of performance and low dose rates under field conditions. These low dose rates, combined with a low level of toxicity to non-target organisms present an outstanding safety profile. This same highly-specific mode of action, however, limits the spectrum of activity and suggests the need for a resistance management plan, both of which must be addressed in new product development. In addition, the biological and physiochemical properties of this, and other new products are not adequately described by the traditional classification of fungicides into“protectant”and“systemic”types. These unique profiles provide novel and useful products for disease control.