• 플랜트 저널
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• 제10권1호
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• pp.34-39
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• 2014

본 연구에서는 상용성 공정모사기인 BR&E사의 PROMAX를 사용하여 amine류 흡수제인 30 wt%의 MEA수용액, 30 wt%의 DEA수용액 그리고 50 wt%의 MDEA수용액과 50 wt%의 MDEA에 첨가제로써 3 wt%의 piperazine을 첨가한 공정을 이용하여 천연가스 중에 포함되어 있는 산성가스인 $CO_2$와 $H_2S$ 성분의 제거 성능에 대한 비교 작업을 수행하였다. 공정모사 결과로 MEA는 상대적으로 많은 $CO_2$를 제거 할 수 있는 반면에 DEA, MDEA, MDEA와 첨가제인 piperazine은 $H_2S$를 많이 제거한다는 것을 알 수 있었고, MEA 30 wt%수용액의 경우는 lean amine의 circulation rate가 가장 적은 것으로 나타냈다. 재비기의 heat duty는 MDEA 50 wt%에 첨가제인 piperazine 3 wt% 수용액이 가장 적음을 알 수 있었다. 또한 MDEA 그리고 MDEA와 첨가제인 piperazine을 비교해 보면 첨가제로 인하여 solvent circulation rate가 감소된 것을 알 수 있었다.

• Corrosion Science and Technology
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• 제18권3호
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• pp.110-116
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• 2019

Resistances to pitting corrosion of additive manufactured (AM) Ti-6Al-4V alloys in 0.6 M NaBr and 0.6 M NaCl aqueous solutions were compared using micro-droplet cell techniques. With respect to the pitting corrosion resistance, this study focused on two different types of halide anions in aqueous solutions, i.e. $Br^-$ and $Cl^-$. The differences between $Br^-$ and $Cl^-$ halide anions for breakdown on passive films of AM Ti-6Al-4V alloy were explained using Langmuir adsorption model with their equilibrium adsorption coefficients. The results of the analysis showed that the lower resistance to pitting potential of AM Ti-6Al-4V alloy in $Br^-$ aqueous solution was attributed to the higher equilibrium adsorption coefficient of Br-. In addition, micro-electrochemical test results showed that the pitting corrosion resistance of dark grains in additive manufactured Ti-6Al-4V alloy was lower as compared to that of bright grains due to the larger volume of ${\alpha}^{\prime}$ phase that caused the susceptibility to pit initiation.

• 멤브레인
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• 제15권1호
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• pp.22-33
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• 2005

비대칭 폴리비닐리덴플루오라이드(PVDF) 막을 상전환법으로 제조하였다. 도포용액은 PVDF를 용매인 N-ethyl-2-pyrrolidone (NMP)와 비용매인 1,4-dioxane, diethyleneglycol dimethyl ether (DGDE), acetone, (equation omitted)-butyrolactone(GBL)의 혼합용매에 녹여서 제조한다. 여러 첨가제가 도포용액 특성, 투과특성과 막 구조에 미치는 영향을 조사하였다. 응고제인 물과 1,4-dioxane, DGDE, acetone과의 상용성이 NMP보다 낮아서 기공크기가 작아진다. 첨가제의 양을 조절하여 기공크기를 변화시켰다. 혼합용매(수계 및 비수계)가 막의 투과성능에 미치는 영향을 살펴보았다. 용액점도뿐만 아니라 표면장력도 용매 투과특성에 영향을 끼침을 알 수 있었다.

• Journal of Pharmaceutical Investigation
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• 제11권3호
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• pp.21-26
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• 1981

The rate of decomposition of calcium thioglycollate in aqueous solution was shown to increase with increasing temperature and with diluting concentration of calcium thioglycollate. The effect of additive on oxidation rate of calcium thioglycollate was studied to prepare the more stable depilatory formula using additives, such as thiourea, mannitol, sodium thiocyanide, nicotinamide, triethanolamine and ethylenediamine. In all cases, the rate of oxidation was reduced when the additive was present in the solution, among them triethanolamine and ethylenediamine inhibited the decomposition rate remarkably. It is assumed that the decomposition reaction in aqueous solution is pseudo-first order reaction.

• 한국결정성장학회지
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• 제13권4호
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• pp.153-156
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• 2003

Pure and Ethylenediaminetetraacetic acid (EDTA) doped L-arginine phosphate (LAP) single crystals were grown from the aqueous solution by temperature lowering method. The effect of EDTA additive on the solubility and metastable zone width of LAP solution has been investigated. Addition of EDTA has enhanced the metastable zone width of LAP and hence bulk crystals could be grown. The growth rate along the [100] direction increases with EDTA additive. Powder X-ray diffraction and FTIR studies reveal the absence of EDTA in the lattice of LAP, This reveals that the addition of EDTA to LAP doesn't influence the crystallinity. However, the transmittance and NLO properties significantly increase with EDTA additive and hence bulk LAP crystals are useful for laser fusion experiments.

• 설비공학논문집
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• 제14권12호
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• pp.1071-1077
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• 2002

Ice adhesion on cooling wall is very important in continuous ice formation. The purpose of the present study is to investigate the possibilities of a three-component aqueous solution as a thermal storage material for the continuous ice formation. By freezing under stirring the solution of 300 mL in a stainless steel vessel which was immersed and cooled in a temperature controlled bath, an ice slurry was formed experimentally with measuring the temperature and stirring load variation. From the experiment, the ice adhesion was suppressed when the supercooling degree decreased and the concentration of aqueous solution increased.

• 약학회지
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• 제23권3_4호
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• pp.147-152
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• 1979

Experiments were carried out to investigate for the interaction between FAD solution and synthetic resin containers made of polyvinylchloride(PVC), polyethylene(PE), and polycarbonate(PC), and for the effect of glycyrrhizine or malic acid on stabilization of FAD in aqueous solution by accelerated stability analysis. Analysis of FAD was determined by means of spectrometer and by separating by paper chromatography and metal ions were detected by atomic absorption spectrophotometer, which were extracted from containers by means of Food and Additive Regulation Standard. The thermal decomposition of FAD in aqueous solution was pseudo first order reaction and it was inhibited by adding glycyrrhizine or malic into the solution. PVC, PE and PC containers accelerated the decomposition of FAD in solution. It is assumed that bivalent heavy metals in resin containers may catalize the hydrolysis of FAD. The metals detected from the containers were Ca, Zn, Cu, Fe, Pb and Cd. And the total amounts of detected metals from PVC were 6.2mcg/cm$^{2}$, PE, 5.5mcg/cm$^{2}$, and PC, 2.7mcg/cm$^{2}$ which were proportional to the rate constant of FAD decomposition in aqueous solution.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1996년도 제11차 KACG 학술발표회 Crystalline Particle Symposium (CPS)
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• pp.129-153
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• 1996

In aqueous slurry processing of silicon nitride, the interaction of dispersant and binder on the surface of particles was studied to identify the effect of these additives on ceramic powder processing. Polymethacrylic acid (PMAA) and polyvinyl alcohol (PVA) were used as dispersant and binder, respectively. the adsorption isotherms of PMAA and PVA for the silicon nitride suspension were determined, while the adsorption of PMAA was differentiated in the mixed additive system by ultraviolet spectroscopy. These experiments were done in order to investigate the effect of these organic additives on the physicochemical properties of silicon nitride suspensions. The electrokinetic behavior of silicon nitride was subsequently measured by electrokinetic sonic amplitude (ESA). As PMAA adsorbed onto silicon nitride, the isoelectric point (pHicp) shifted from pH=6.7 to acidic pH, depending on the surface coverage of PMAA. However, adsorption of PVA did not change the pHicp of suspensions, but did decrease the surface potential of silicon nitride moderately. The rheological behavior of silicon nitride suspensions was measured to assess the stability of particles in aqueous media, and was correlated with the electrokinetic behavior and adsorption isotherm data for silicon nitride.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.397-400
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• 1997

This paper presentes the characteristics of Si anisotropic etching and electrochemical etch-stop in aqueous TMAH/IPA/pyrazine solution. (100) Si etching rate of 0.747 $\mu\textrm{m}$/min which faster 86% than TMAH 25 wt.%/IPA 17 vol.% solution was obtained using best etching condition at TMAH 25 wt.%/IPA 17 vol.%/pyrazine 0.1 g and the etching rate of (100) Si was decreased with more additive quantity of pyrazine. I-V curve of p-type Si in TMAH/IPA/pyrazine was obtained. OCP(Open Circuit Potential) and PP(Passivation Potential) were -2 V and -0.9 V, respectively. Si diaphragms were obtained by electrochemical etch-stop in aqueous TMAH/IPA/pyrazine solution.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 가을 학술논문 발표대회
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• pp.141-142
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• 2020

In this study, the performance evaluation was performed by adding a polymer aqueous solution as a new additive of the red clay binder for use in the rammed earth construction method. The evaluation items were compressive strength and microstructure analysis. As a result of the experiment, the performance of the red clay binder was improved by efficiently bonding the silica particles by the polymerized polymer.