• Polymer(Korea)
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• v.32 no.6
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• pp.523-528
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• 2008

Diglycidyl ether of bisphenol-A (DGEBA) was selected as a compatibilizer in Nylon 6 and bisphenol-A polycarbonate (PC) blends. SEM revealed a much finer morphology in the presence of DGEBA. The thermal properties, such as glass transition, melting point, crystallization temperature and rate, of the blends were examined using DSC. Overall, the introduction of DGEBA caused a strong dependence of these thermal properties on the composition due to compatibilization.

• Journal of Environmental Science International
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• v.15 no.5
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• pp.471-477
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• 2006

We investigated the relationship between the $TiO_2$ photocatalytic decomposition of bisphenol A in water and biological toxicity to zebrafish (Danio rerio) during $1\sim28$ weeks post development stage. The bisphenol A in water was completely degraded by the $TiO_2$ photocatalysis in 50 hours. After the photocatalysis, no toxic effects on the morphogenesis of the zebrafish were observed during the development, growth, and maturate stages. Catalase activity of control group was not different from $1\sim5$ week post fertilized group. However, toxic effect on the catalase activity of adult stage(28 weeks) decreased 50% than control group.

• Environmental Analysis Health and Toxicology
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• v.21 no.4 s.55
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• pp.301-310
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• 2006

본 연구에서는 내분비계장애물질로 잘 알려진 Bisphenol A와 Ethynyl estradiol(이하 BPA, EE)이 Chironomus riparius에 미치는 영향을 알아보고자 하였다. 수생생태계에서 Chironomus의 생태학적 중요성을 고려하여 연구한 반수치사농도(LC50),효소 활성, 성장/발달 등의 생화학적, 생리학적 독성에 대한 연구는 이들 물질에 대한 잠재적인 생태학적 중요성을 이해하는데 있어 유용한 정보를 제공할 수 있을 것이다. 연구 결과 BPA와 EE에 노출된 후 C. riparius게서 CAT와 GST활성이 증가하였고, EE에 고농도로 노출된 후 성충까지 충분히 성장하지 못했음을 확인하였다 이러한 결과로부터 C. riparius에서 BPA, EE에 대한 중요한 독성정보를 얻을 수 있었다. 그러므로 앞으로 BPA와 EE의 생화학적 효과와 C. riparitis의 개체수준 이상에서의 생리학적 실험을 통한 검증이 필요할 것이다.

• Journal of the Korean Applied Science and Technology
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• v.34 no.1
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• pp.25-32
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• 2017

Such electrical properties (dielectric permittivity and dielectric loss of epoxy resin with the variations of frequency (30 ~ 300k Hz) and temperature ($20{\sim}160^{\circ}C$) have been measured. Dielectric dissipation of three specimen did not occurred below the glass transition temperature (Tg) regardless of frequency, but occurred above its temperature.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.22-23
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• 2017

The purpose of this study is to ascertain self-healing function on microcracks in bisphenol F-type epoxy-modified mortars using expansive admixtures. The specimens are prepared with various polymer-binder ratios of 0, 5, 10, 20%, expansive admixture contents of 0% and 10%, a sodium carbonate content of 0.25%, and subjected to exposure conditions of CR1, CR2, CR3 and CR4. The specimens are tested for self-healing effect, porosity and FE-SEM analysis. As a result, self-healing effects of bisphenol F-type EPMMs with expansive admixtures are visible in all of the outdoor exposure conditions. In particular, exposure conditions of CR3 and CR4 are most noticeable. And the porosity of EPMMs is reduced with an increase in the polymer-binder ratio, and is considerably smaller than that of unmodified mortar.

• Journal of Food Hygiene and Safety
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• v.36 no.6
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• pp.528-536
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• 2021

The purpose of the study was to investigate the content of sinigrin, an index component, in Brassica juncea extract and to evaluate the differentiation of lipocytes, inhibition of production of reactive oxygen species (ROS) and reduction of protein production by lipogenic factors (PPARγ, C/EBPα, aP2) in the processing of Brassica juncea extract and sinigrin in 3T3-L1 preadipocytes which induces Bisphenol A (BPA), an endocrine disrupting environmental hormone. From the investigation, the content of sinigrin in Brassica juncea extract, measured by HPLC, is found to be 21.27±0.2 mg/g. The XTT assay result on BPA-derived 3T3-L1 adipocytes shows there is no cytotoxicity found from 180 µM of sinigrin and 300 ㎍/mL of Brassica juncea extract. Moreover, both intracellular lipid accumulation and ROS production during differentiation of lipocyte are significantly reduced in cells processed with Brassica juncea extract and sinigrin. Lastly, it was also found that the production of transcription factors of lipocyte differentiation, PPARγ, C/EBPα and aP2, were found to be suppressed by the application of Brassica juncea extract and sinigrin. Such results reveals that Brassica juncea is effective in not only suppressing lipid accumulation in the environmental hormone bisphenol A-derived lipocyte, but also in reducing the ROS. The sinigrin-containing Brassica juncea is highly expected to be used in natural functional supplements that prevents the lipid metabolism disorders caused by BPA. There are necessities for additional clinical research and follow-up studies on the in vivo model to verify the relevant mechanisms.

• Applied Chemistry for Engineering
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• v.26 no.3
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• pp.311-318
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• 2015

This work investigated the plasma treatment of aqueous bisphenol A (BPA) solution and mineralization pathways. For the effective contact between plasmatic gas and aqueous BPA solution, the plasma was created inside a porous ceramic tube, which was uniformly dispersed into the aqueous solution through micro-pores of the ceramic tube. Effects of the gas flow rate, applied voltage and treatment time on the decomposition of BPA were examined, and analyses using ultraviolet (UV) spectroscopy, ion chromatography and gas chromatography-mass spectrometry were also performed to elucidate mineralization mechanisms. The appropriate gas flow rate was around $1.0L\;min^{-1}$; when the gas flow rate was too high or too low, the BPA decomposition performance at a given electric power decreased. The increase in the voltage improves the BPA decomposition due to the increased electric power, but the energy required to remove BPA was similar, regardless of the voltage. Under the condition of $1.0L\;min^{-1}$ and 20.8 kV, BPA at an initial concentration of $10L\;min^{-1}$ (volume : 1 L) was successfully treated within 30 min. The intermediates produced by the attack of ozone and hydroxyl radicals on BPA were further oxidized to stable compounds such as acetate, formate and oxalate.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.248-251
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• 2008

일반적으로 phthalate esters의 전처리방법에는 액액추출법(liquid-liquid extraction), 고상추출법(Solid-phase Extraction, SPE), 고상미세추출법(Solid-phase micro extraction, SPME) 등의 분석방법이 있다. 그 중에서 본 연구에서는 SPE를 이용하여 간편하고 정확성이 높으며, 적은 양의 유기용제를 사용하여 전처리함으로써 2차적인 환경오염을 줄일 수 있다는 점에서 다른 전처리 방법보다 유용하다고 할 수 있다. 검출감도 측면에서 phthalate esters의 경우는 구조적으로 안정적인 편이나 페놀류의 경우 hydroxy group 때문에 GC/MS 분석시 유도체화 과정이 필수적인데 이번 연구에서 사용한 BSTFA/TMCS는 비교적 쉽고 빠르게 유도체 화할 수 있다는 이점이 있다. 더 많은 연구가 필요하겠지만 앞서서의 결과에서도 알 수 있듯이 전반적으로 검출한계가 0.05$\sim$0.5 $\mu$g/L 정도로 높고, 4-nonyl phenol을 제외하고 80% 이상의 양호한 회수율을 나타낸 것으로 미루어 보아 phthalate esters, phenols의 효율적인 동시분석이 가능함을 알 수 있다.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.272-274
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• 2008

일반적으로 프탈레이트 에스테르의 전처리방법에는 액액추출법(Liquid Liquid Extraction, LLE), 고상추출법(Solid Phase Extraction, SPE), 고상미세추출법(Solid Phase Micro Extraction, SPME) 등의 분석방법이 있다. 그 중에서 본 연구에서는 간편하고 정확성이 높은 SPE를 이용하였으며, 적은 양의 유기용제를 사용하여 전처리함으로써 2차적인 환경 오염을 줄일 수 있다는 점에서 다른 전처리 방법보다 유용하다고 할 수 있다. 또한 프탈레이트 에스테르의 경우는 구조적으로 안정적인 편이나 페놀류의 경우 hydroxy group 때문에 GC/MS 분석시 유도체화 과정이 필수적이나 이번 연구에서는 HPLC를 이용하므로 별도의 유도체화의 번거로움 없이 바로 분석할 수 있는 이점이 있다. 더 많은 연구가 필요하겠지만 앞서서의 결과에서도 알 수 있듯이 전반적으로 검출한계가 0.1$\sim$0.5$\mu$g/L 정도로 높고, 82% 이상의 양호한 회수율을 나타낸 것으로 미루어 보아 극미량 분석이 아닌 이상, 산업체에서 HPLC의 이용이 더욱 유리할 것이라고 사료된다.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.05a
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• pp.252-254
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• 2005

음용수 처리공법으로 BPA를 분해하는 TiO$_{2}$광분해과정의 생물학적 안전성을 zebrafish(Danio Rerio, wild type)의 발생과 성장기를 통해 알아보았다. TiO$_{2}$ 광분해는 BPA를 제거하는 효과가 있었으며, TiO$_{2}$ 광분해 환경에서 부화된 자어의 경우 배발생 초기와 성장기, 성체시기에 형태적인 이상을 보이지 않았다. 그러나 항산화효소인 catalase 의 활성도는 발생초기와 부화 1, 5주에는 대조군에 비해 별다른 차이가 나타나지 않았으나 28주의 성체기에는 활성도가 절반 이하로 떨어지는 자체방어계의 이상을 보였다.