• 한국산업보건학회지
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• 제15권3호
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• pp.270-276
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• 2005

This study was conducted to examine whether a specific synthetic metalworking fluid (MWF), "A", in use for 10 months without replacement, displayed microbial resistance and to identify the additives associated with the control of microbial growth. Three synthetic MWF products ("A", "B", and "C") were studied every week for two months. Microbial deterioration of the fluids was assessed through evaluation by endotoxin, bacteria and fungi levels in the MWFs. In addition, formaldehyde, boron, ethanolamine, and copper levels were also studied to determine whether they influence microbial growth in water-based MWFs. Throughout the entire study in the sump where MWF "A" was used, bacteria counts were lower than 103 CFU/mL, and endotoxins never exceeded 103 EU/mL. These levels were significantly lower than levels observed in sumps badly deteriorated with microbes. Boron levels in MWF "A" ranged from 91.7 to 129.6 ppm, which was significantly higher than boron levels found in other MWF products. The total level of ethanolamine (EA) in MWF "A" ranged from 35,595 to 57,857 ppm (average 40,903 ppm), which was over ten times higher than that found in other MWFs. Monoethanolamine (MEA), diethanolamine (DEA) and triethanolamine (TEA) concentrations in MWF "A" were also significantly higher than seen in other MWFs. However, although EA and boron might improve anti-microbial performance, their abuse can pose a serious risk to workers who handle MWFs. From an industrial hygiene perspective, our study results stress that the positive synergistic effect of boron and EA in reducing microbial activity in MWF must be balanced with the potentially negative health effects of such additives. Our study also addresses the disadvantage of failing to comprehensively report MWF additives on Material Safety Data Sheets (MSDS). Future research in MWF formulation is needed to find the best level of EA and boron for achieving optimal synergistic anti-microbial effects while minimizing employee health hazards.

• Journal of Pharmaceutical Investigation
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• 제37권3호
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• pp.173-177
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• 2007

The purpose of this study was to investigate the effect of salt formation on the percutaneous absorption of meloxicam through hairless mouse skin from a pressure sensitive adhesive (PSA) matrix. In addition, the influences of enhancers on the permeation of meloxicam or meloxicam-ethanolamine (MX-EA) salts across the hairless mouse skin were evaluated using a flow-through diffusion cell system. The salt formation of meloxicam resulted in lower permeation rate than the parent drug. $Span^{(R)}$ 80 provided the highest enhancing effect for meloxicam and meloxicam monoethanolamine salt. The maximum amount of the drug that can be loaded without retarding permeation rate was different depending on the compound. No relationship was found between the fluxes of meloxicam or MX-EA salts from saturated solutions and those from PSA matrices containing the same enhancer.

• 대한화학회지
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• 제36권6호
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• pp.947-954
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• 1992

Poly (γ-benzyl L-glutamate) (PBLG)와 말단에 아미노기를 갖는 Polyethylene glycol (PEG)의 치환반응을 행하여 PEG-grafted PBLG (PEG-g-PBLG)를 합성하였다. 또한 PEG-g-PBLG 필름표면에 ethanolamine(EA)을 치환반응하여 표면에 히드록시그룹을 갖는 PEG-g-PBLG-EA 필름을 얻었다. 폴리펩티드중합체와 혈액성분과의 상호작용에 관한 실험결과, PEG-g-PBLG 상에서의 혈소판의 점착율 및 형태변화는 PEG-g-PBLG-EA보다 적게 나타났고, PEG-g-PBLG상에서의 혈장 단백질의 응고시간은 PEG-g-PBLG-EA 또는 PBLG의 응고시간보다 길게 나타났다. 이들 결과는 혈액응고시간 및 혈액응고량을 조사한 실험결과와 일치하였다. 따라서 폴리펩티드상의 히드록시그룹은 혈액성분과의 상호작용을 강하게 하여 혈액적합성이 저하하는 반면, PEG-g-PBLG는 비교적 좋은 혈액적합성을 나타냄을 알 수 있었다.

• 한국산업보건학회지
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• 제15권1호
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• pp.52-60
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• 2005

This study was carried to assess the accuracy of material safety data sheets (MSDS) for some water-soluble metalworking fluid (MWF) with respect to mono- ethanolamine(MEA), di-ethanolamine(DEA) and tri-ethanolamine (TEA). 39 fresh and 52 used MWFs for this study were taken from the workplace. The quantification and qualification of MEA, DEA and TEA were done using ion-chromatography. Three main findings of this study were 1) EA that was not addressed in material safety & data sheets (MSDS) was found to be enough higher than 1%, 2) 33.3% of 39 fresh MWF showed ingredient and concentration of MEA, DEA and TEA in MSDS and 3) the concentrations of MEA(20.5%), DEA(41.3%) and TEA(15.4%) were much higher than those indicated in MSDS. Consequently, we concluded that the accuracy on ingredients and concentrations of MEA, DEA and TEA provided in MWF was very low. Our study recommends that the limit concentration of chemical except for carcinogen that employer has to indicate in MSDS should be lowered from 1% to 0.1% .

• Journal of Industrial and Engineering Chemistry
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• 제67권
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• pp.407-416
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• 2018

This study presents a novel complete solution starting with a synthesis of silica modified with potassium-nickel hexacyanoferrate and ethanolamine (SiEA-KNiFe) sorbent through radiocesium sorption in different process configurations and moving on to the vitrification of the spent sorbent, using the sol-gel method. The experimental data for deionized water solution, as well as seawater solution, correlates strongly with the Langmuir isotherm model. Moreover, the study also presents a method for spent sorbent solidification in the glass matrix. The cesium leaching test confirmed that spent sorbent can be stably bound in the glass matrix after radionuclide removal.

• Safety and Health at Work
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• 제1권2호
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• pp.175-182
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• 2010

Objectives: This study examined how ethanolamines (EAs) with the same functional alcohol group ($HOCH_2CH_2$), such as mono-EA (MEA), di-EA (DEA), and tri-EA (TEA), in water-based metalworking fluids (wbMWFs) are vaporized, condensed, and transformed by heat generated during metalworking. Methods: Two types of experimental apparatus were manufactured to achieve these objectives. Results: Vaporization tests using a water bath showed that the vaporization rate increased markedly from $0.19\;mg/m^2{\cdot}min$ at $23.5^{\circ}C$ to $8.04\;mg/m^2{\cdot}min$ at $60^{\circ}C$. Chamber tests with a heat bulb revealed that "spiked" MEA was fully recovered, while only 13.32% of DEA and no TEA were recovered. Interestingly, non-spiked types of EAs were detected, indicating that heat could convert EAs with more alcohol groups (TEA or DEA) into other EAs with fewer group(s) (DEA or MEA). The EA composition in fresh fluid was 4% DEA, 66% TEA, and 30% MEA, and in used fluids (n = 5) was 12.4% DEA, 68% TEA, and 23% MEA. Conversion from TEA into DEA may therefore contribute to the DEA increment. Airborne TEA was not detected in 13 samples taken from the central coolant system and near a conveyor belt where no machining work was performed. The DEA concentration was $0.45\;mg/m^3$ in the only two samples from those locations. In contrast, airborne MEA was found in all samples (n = 53) regardless of the operation type. Conclusion: MEAs easily evaporated even when MWFs were applied, cleaned, refilled, and when they were in fluid storage tanks without any metalworking being performed. The conversion of TEA to DEA and MEA was found in the machining operations.

• Membrane and Water Treatment
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• 제9권6호
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• pp.385-392
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• 2018

Poly vinyl chloride (PVC) was chemically modified, and used for ultrafiltration to analyze the performance. Non-solvent induced phase separation (NIPS) method was used to prepare membranes. The neat PVC membrane was casted and used as a control membrane. Modified membrane was prepared by reacting PVC with ethanolamine (EA) in the casting solution (labeled as CM-PVC). Pure water permeability (PWP) was evaluated by measuring pure water flux. Humic acid was used as model foulant solute to analyze flux and rejection ability of membranes. Flux and rejection data of neat and modified membranes were compared to prove the improvement in the filtration performance. The experimental results showed that for PVC and CM-PVC, PWP was calculated to be ~64 and ${\sim}143L/m^2{\cdot}h$, respectively, and the rejection of humic acid was found to be 98% and 100%, respectively. TGA was carried out to analyze the effect of chemical modification on the thermal stability of polymer. FT-IR analysis was another characterization technique used for the comparative study.

• 한국식품영양과학회지
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• 제24권6호
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• pp.867-873
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• 1995

만성적인 알코올 섭취가 미토콘드리아의 지질조성 및 ATPase 활성도에 미치는 영향을 조사하고 아울러 간의 발암물질인 2-AAF를 토여하여 간 미토콘드리아의 기능에 미치는 상호 효과를 조사하기 위하여 120~125g 숫쥐에게 열량의 35%를 알코올로 공급하여 6주간 사육하였으며 알코올 섭취 4주 후에 2-AAF를 3일 간격으로 2회 복강투여하여 실험한 결과를 요약하면 다음과 같다. 1. 체중 증가, 식이 섭취량 및 식이효율에 대한 알코올의 효과는 유의적인 차이를 보였으나, 2-AAF에 의한 유의적인 효과는 관찰할 수 없었다. 알코올 섭취군이 대조군 보다 체중은 유의적으로 감소하였다. 2. 미토콘드리아 ATPase 활성도는 알코올 섭취에 의해 유의적으로 감소되었고, 2-AAF 투여에 의해서는 유의적이지 않으나 감소되는 경향을 보였다. 따라서 대조군(C)에 비하여 알코올 섭취와 2-AAF투여군(EA)에서 ATPase 활성도가 29.3%의 감소를 나타냈다. 3. 간 미토콘드리아 콜레스테롤 함량은 알코올 섭취에 의해 유의적으로 증가하였으며 미토콘드리아 총 인지질량은 알코올과 2-AAF에 의한 상호작용에 의해 알코올 투여군에서만 2-AAF 투여시 유의적인 증가 효과를 보여주었다. C/PL 비율은 알코올 섭취와 2-AAF 투여 보두에서 유의적인 효과는 보이지 않았으나 군간 비교시 알코올군(E)이 대조군(C) 보다 유의적으로 증가하였다. 4. 간 미토콘드리아의 CL량은 알코올군에서 감소하는 경향을 보였고 PS와 PI량은 차이가 없었다. 알코올 섭취로 PC량은 유의적으로 증가하였으나 PE량은 차이가 없엇으며, 2-AAF 투여시 PC량은 유의적인 감소를 보였고 PE량은 유의적으로 증가하였다. PE/PC 비율은 알코올 투여에 의해 유의성은 없었으나 감소경향을 나타냈으며, 2-AAF 투여에 의해서는 유의적인 증가 효과가 나타났다. 5. 알코올 섭취시 미토콘드리아의 지방산 조성은 palmitic acid가 유의적으로 감소하였고, stearic acid는 유의적으로 증가함을 보였다. UFA/SFA와 UI는 알코올군에서 유의적이지는 않으나 증가되는 경향을 보였다. 2-AAF 투여에 의해서도 linoleic acid는 감소되고 arachidonic acid는 증가되는 경향을 보여 UI값이 증가되는 경향이 있었다. 따라서 본 실험에서 나타난 ATPase 호라성도 변화는 비토콘드리아의 콜레스테롤변화, C/PL 비율, 인지질 조성이나 지방산 조성의 변화 등 막지질 조성의 변화에 기인하는 것으로 생각된다.