Physicochemical properties between pristine and aged AgNPs for the evaluation of nanotoxicity

최중소,엄하늬,심재훈,신현호,김영훈 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.6

The use of nanomaterials in industrial and commercial applications is growing, and official reports concerning the possible environmental and health effects of nanoparticles are steadily increasing. An understanding of the potential toxicity of nanomaterials is important for creating sustainable and safe nanotechnologies. To test the cytotoxicity of nanomaterials, quantitative and qualitative analyses of raw nanomaterials should be priorities. However, the fundamental properties of raw materials will change compared to those of aged materials in biological media due to the interaction between nanomaterials and media composition. Therefore, the correlation and interdependence between pristine physicochemical properties (PChem) of raw nanomaterials before the toxicity test and aged PChem in biological media were evaluated using modified test guidelines originally suggested by the OECD WPMN (Organization for Economic Cooperation and Development, Working Party on Manufactured Nanomaterials) for peer-reviewed papers concerning silver nanoparticles, during the period of 2005 to 2010. In addition, we investigated whether the suggested analysis tools are applicable to define the PChem of AgNPs with regard to cytotoxicity.

방향족 수질오염원의 무한희석 활동도 계수의 측정 및 예측

최중소 광운대학교 신기술연구소 1999 신기술연구소논문집 Vol.28 No.-

수질을 오염시키는 방향족 화합물의 열역학적 거동을 설명하기 위하여 gas chromatograph(GC)을 이용하여 solute(1)/water(2)계에 대하여 333.15K~413.15K의 온도범위에서 무한희석 방향족 화합물의 활동도 계수가 측정되었다. 활동도 계수는 온도가 상승함에 따라 감소하는 결과로 나타나 오염성분의 처리가 저온보다는 고온영역에서 잘 이루어질 수 있다는 기준을 제시하였다. 무한희석시 물 속에서 용질의 활동도 계수를 예측하기 위하여 group contribution 모델인 UNIFAC이 적용되었고, 예측 결과는 실험치에 비교하여 10% 미만의 예측 오차범위에서 만족할 만한 결과를 얻었다. Infinite dilution activity coefficients were measured with a gas chromatograph to investigate the thermodynamic behavior of each aromatic compound which polluted the water for solute(1)/water(2) systems within 333.15K to 413.15K. They were decreased according to an increment of temperature and their results proved that the treatment of a pollution component of water get accomplished well in the high temperature region than in the low temperature range. The UNIFAC was applied to predict the infinite dilution activity coefficients of each solute in water. The predicted values were agreed with the experimental data within the 10% error ranges.

액-액계에서 분자간의 상호작용에너지에 대한 염의 영향

최중소 光云大學校 1991 論文集 Vol.20 No.-

The binodal curves and tie lines were determined for monochlorobenzene-MgCl₂ salt solution acetone system at 25℃. MgCl₂ salt solution were prepared with 5%~30%(wt.%) aqueous solutions of 5% interval respectively toward saturated concentration. The parameters in NRTL, UNIQUAC, modified UNIQUAC models were determined with only experimental tie lines by least-squares method to predict the values of tie lines. And the phenomena on improvement of solvent-extraction performance were described by using the estimated parameters.

팽윤모델에 의한 실리콘고무의 팽윤거동 계산

최중소 광운대학교 신기술연구소 1998 신기술연구소논문집 Vol.27 No.-

경도 35인 실리콘고무에 대한 정용매(good solvent). 부용매(poor solvent)를 선정하여 실리콘고무(Poly(dimethlysiloxane) . PDMS)와 혼합 유기용매로 이루어진 ethylacetaet(1)/methanol(2)/PDMS(3) 및 xylene(1)/methanol(2)/PDMS(3)계에 대하여 팽윤평형시의 각 성분의 부피분율이 측정되었다 PDMB를 팽윤촉진시키는 정용매로는 xylene과 ethyl acetate를, 팽윤을 억제시키는 부용매로는 methanol을 선택하였다. 팽윤데이타를 이용하여 PDMS의 팽윤에 대한 용매의 농도에 따른 영향. 온도의 영향을 고찰하고. 팽윤평형데이타를 이 팽윤모델에 상호연관시켜 각 성분의 상호작용에너지 파라미터를 추산하였다. 추산결과, 실험치와 계산치는 양호한 일치를 보였다. The volume fractions of each component on swelling equilibria were measured for ethyl acetae(1)/methanol(2)/PDMS(3) and xylene(1)/methanol(2)/PDMS(3) systems by selecting the ethyl acetate and the xylene as the good solvent and the methyl alcohol as the poor solvent against the PDMS. The hardness of silicone rubber was a 35 grade. The concentration and the temperature effect on the swelling equilibria were described for swelling of the PDMS. And the experimental data of swelling equilibria were correlated with the swelling models and used to estlmate the interchange energy Parameters between the each component. The calculated values were agreed with the experimental data.

활성슬럿지에 의한 Phenol 분해에 관한 연구

최중소 光云大學校 1990 論文集 Vol.19 No.-

Research was undertaken for the purpose of knowing application of Monod-type kinetic models without substrate inhibition and selecting the best model when microbial degradate phenol was acting as the growth limiting substration. To investigate the steady state behavior of heterogeneous microbial population, complete mixing. aeration tank without cell recycle was used under isothermal and continuous flow condition. Multiresponse data obtained through experiments in an aeration tank were correlated to estimate the parameters in various models by using the least squares criteria and an iterative minimum search technique. The six models of Monod, Two-phase, Teissier, Contois, Moser, Grau, With microbial decay coefficients were compared in this study, The selection of model among those investigated was carried out by employing the F-test and analysis of the sum of squares of residuals. As a result, the model proposed by Contois was significantly better than the other models tested, but Two-phase model, Teissier model were not fitted to express CMAS process.

용매추출에 대한 염첨가제의 영향

최중소 光云大學校 1990 論文集 Vol.19 No.-

For considering the salt effect on monochlorobenzene which was selected optimally by literature, the binodal curve and the tie lined were measured for monochlorobenzen-salt solution- acetone, and the salt solutions were prepared with the aqueous solution of 5%, 10%, 15%(weight percent) for NaCl, MgCl₂, CaCl₂, KCI and KNO₃, respectively. The consistency of the tie line data was tested by correlating with the Eisen-Joffe equation. And the salt effect on the best solvent was considered by comparing the binodal curves and the distribution curves of each salt solution with those of no salt solution. As a result, the MgCl₂ was found to be the best one of used salts.

2상계를 이루는 고분자용액에 대한 분자모델의 적용

최중소 光云大學校 1994 論文集 Vol.23 No.-

Experiment of liquid-liquid equilibria was carried out for PEG-dextran-water systems which were partially miscible at 25℃. Molecular weights of PEG were 2,000, 8,000, 10,000 and those of dextrans were 9,300, 40,800. Determination of solubility curves were carried out by titration method and compositions of tie line was measured by refractometer and UV-visible spectrophotometer. On the other hand, tie line data were correlated with NRTL and UNIQUAC models that are low molecular weight models, and were used to determine parameter of models. As results. calculated values agreed with the data within 10% error ranges.

2상계를 이루는 고분자용액에 대한 분자모델의 적용

최중소(Joong So Choi) 광운대학교 인문사회과학연구소 1994 인문사회과학논문집 Vol.23 No.-

다양한 촉매에 의한 Poly(ethylene-co-1,4-cyclohexylenedimethylene)Terephthalate Oligomer 형성기 반응기작

박상순 한국화학공학회 2004 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.42 No.3

폐타이어 분말을 이용한 자체보수성 방수재 개발

이동민,최중소,Lee Dong-Min,Choi Joong-So 한국자원리싸이클링학회 2005 資源 리싸이클링 Vol.14 No.4

Four sheet-shaped and one soft-shaped self-sealing waterproof materials were prepared to recycle some GRT(Ground Rubber Tires). Their physical properties were tested to consider characteristics of them. The self-sealing waterproof materials were consisted of GRT/super absorbent polymer(SAP)/binder and mold by a hot press after mixing with a batch-typed internal mixer. The average size of GRT particles was -40 mesh, SAPs were commercial GE-500F and poly(AM-SAS-AA) prepared in this work. Binders were PU. EVA, LDPE, SBR, and poly(2-EHA). And PU film was attached to improve the properties of waterproof materials. Characteristics of self-sealing waterproof materials consisted of by GRT/GE-500F/EV-600/PU film and GRT/GE-500F/SBR(vulcanization)/PU film among the developed self-sealing waterproof materials were similar to the commercial products. And properties of the soft-shaped self-sealing waterproof materials consisted of by GRT/GE-500F/Po1y(2-EHA) and CRT/Poly(AM-SAS-AA)/poly(2-EHA) were improved within from four times to twenty times compared to the one oi the commercial products. 폐타이어 분말(GRT)을 재활용하기 위하여 sheet type 4그룹과 soft type 1그룹의 자체보수성 방수재를 제조하였다. 각각 방수재의 방수특성을 고찰하기 위하여 방수재들의 물성을 측정하였다. 방수재는 GRT/ 고흡수성수지/ binder로 구성되었으며, internal mixer로 혼합한 후 hot press로 성형하여 제조 되었다. 방수재 제조에 사용된 CRT의 평균입도는 -40mesh 이었고, 고흡수성 수지는 상용품과 poly(AM-SAS-AA)를 제조하여 사용하였고, binder는 PU, EVA, LDPE, SBR, poly(2-EHA)을 사용하였다. 또한 방수재의 물성을 향상시키기 위하여 보강재로 PU film을 사용하였다. 폐타이어 분말을 이용하여 개발된 sheet type 자체보수성 방수재 중 GRT/ CE-500F/EV-600/PU film 과 GRT/GE-500F/SBR(vulcanization)/PU film 로 구성된 방수재가 기존 상용제품의 물성에 근접하였다. 또한 soft type 방수재는 GRT/GE-500F/Poly(2-EHA)와 GRT/P(AM-SAS-AA)/Poly(2-EHA)로 구성된 방수재가 상용제품의 흡수능보다 4-20배의 개선된 결과를 나타내었다.