The high-temperature stability of YSZ specimens fabricated by die pressure and cold isostatic press (CIP) is investigated in CaCl2-CaF2-CaO molten salt at 1,150 °C. The experimental results are as follows: green density 46.7 % and 50.9 %; sintering density 93.3 % and 99.3 % for die press and CIP, respectively. YSZ foremd by CIP exhibits higher stability than YSZ formed by die press due to denseness dependency after high-temperature stability test. YSZ shows peaks mainly attributed to CaZrO3, with a small t-ZrO2 peak, unlike the high-intensity tetragonal-ZrO2 (t-ZrO2) peak observed for the asreceived specimen. The t-ZrO2 phase of YSZ is likely stabilized by Y2O3, and the leaching of Y2O3 results in phase transformation from t-ZrO2 to m-ZrO2. CaZrO3 likely forms from the reaction between CaO and m-ZrO2. As the exposure time increases, more CaZrO3 is observed in the internal region of YSZ, which could be attributed to the inward diffusion of molten salt and outward diffusion of the stabilizer (Y2O3) through the pores. This results in greater susceptibility to phase transformation and CaZrO3 formation. To use SOM anodes for the electroreduction of various metals, YSZ stability must be improved by adjusting the high-density in the forming process.

The diesel engine generate many pollutants such as PM(Particulate matter) and NOx(Nitrogen oxide). So the SCR(Selective catalytic reduction) must be required to meet the emission standard. The SCR catalyst market is growing rapidly, and the automobile markets using alternative energy sources are growing rapidly. This study deals with optimization of the calcination process the manufacturing process of SCR catalyst to be competitive. The calcination process is a bottleneck and it is required to optimize productivity and accept to be safety, But we cannot trade off anything in terms of safety. We applied DOE(Design of experiments) among many research methods performed in various fields. In order to achieve quality and productivity optimization. The dependent variables in the DOE were selected as NO Conversion(%). The independent variables were selected as the calcination temperature, soaking time and fan speed RPM. the CCD(Central composite designs) constructs response surface using the data onto experience and finds optimum levels within the fitted response surfaces. Our tests are our stability guarantee and efficient together with operation.

Saline water electrolysis is an electrochemical process to produce valued chemicals by applying electric power. Perfluorinated sulfonic acid (PFSA) ionomers have been used as polymer electrolyte membrane (PEM) materials owing to their high sodium ion selectivity and barrier properties. However, sulfonic acid groups in PFSA ionomers are chemically decomposed under a basic catholyte condition, which makes the PEM materials lose their ionic selectivity and Faraday efficiency. In this study, double layered membranes were prepared by anchoring cross-linked hydrocarbon ionomers, as a protection layer to catholyte atmosphere, into the water channels, particularly, located at around the surface of a PFSA membrane. Here, each monomer results in the identical chemical architecture and different free volume content when polymerized.

In the present study, we investigate the effects of milling time and the addition of a process control agent (PCA) on the austenite stability of a nanocrystalline Fe-7%Mn alloy by XRD analysis and micrograph observation. Nanocrystalline Fe-7%Mn alloys samples are successfully fabricated by spark plasma sintering. The crystallite size of ball-milled powder and the volume fraction of austenite in the sintered sample are calculated using XRD analysis. Changes in the shape and structure of alloyed powder according to milling conditions are observed through FE-SEM. It is found that the crystallite size is reduced with increasing milling time and amount of PCA addition due to the variation in the balance between the cold-welding and fracturing processes. As a result, the austenite stability increased, resulting in an exceptionally high volume fraction of austenite retained at room temperature.

본 연구에서는 용액 공정으로 제작된 단분자 기반의 유기 반도체 전계효과 트랜지스터에 적용된 보호막이 유기 트랜지스터의 전기적 안정성에 미치는 영향에 대해여 살펴보았다. Solvay社에서 제공한 용액 공정형 유기 단분자 반도 체를 채널로 사용하여 제작한 유기 트랜지스터는 약 1 cm2/Vs의 상대적으로 높은 이동도를 보였으며, 대략 2.5 ~ 20 k Ωcm 범위의 낮은 접촉저항을 가진 것으로 측정되었다. 무엇보다 중요한 것은, 제작한 유기 트랜지스터에 불소원자가 함유된 Hyflon AD를 보호막으로 적용하였을 때, 보호막을 적용하기 전에 비해 훨씬 더 향상된 전기적 안정성을 보였 다. 이는 불소원자가 함유된 Hyflon AD 고분자막이 대기 중의 수분을 효과적으로 차단하기 때문으로 추측된다.

두유는 단백질, 지질, 다당류 등이 에멀션과 서스펜션 형태로 혼합된 분산 시스템이다. 두유의 안정성은 제조조건과 균질화 방법에 따른 입자의 크기와 열처리 조건 등에 의하여 크게 영향을 받으며, 일반적으로 점증제와 계면활성제를 사용하여 향상시킬 수 있는 것으로 알려져 있다. 본 연구에서는 양친매성의 진세노사이드를 함유한 인삼 분말의 첨가와 열처리가 고압 균질화하여 제조한 비지 분리 두유의 안정화에 미치는 영향을 분석하였다. 전두유의 비지를 분리한 후 2% (w/w)의 인삼 분말을 첨가하였으며, 이때 진세노사이드 함량(Rg1, Rb1, 및 Rg3의 합량)은 0.088 mg/100g soy milk 이었다. 이후 두유를 열처리(90°C, 10 min)하거나 열처리 하지 않고 고압 균질화(4500 psi)하여 인삼 분말을 함유한 비지 분리 두유를 제조하였다. 제조한 두유 샘플들의 고형분 함량은 6.7-7.5% (w/w), pH는 6.4-6.8, 제타 포텐셜은 -7-0.3 mV, 입도 크기는 17-23 μm 범위에서 측정되었다. 두유의 저장 안정성은 두유를 45 ml 유리관에 넣고 25°C에서 144 h 동안 저장하면서 분리된 상층부와 하층부의 입도크기, 투과도, 상분리 현상 등을 측정하여 분석하였다. 인삼 분말을 첨가하지 않은 비열처리 두유의 경우, 저장 중 상층부의 입도 크기는 21.6±0.2 μm에서 6.6±0.4 μm로 감소하였고 투과도는 5.2±0.0%에서 77.3±0.1%로 급격히 증가하였다. 2%의 인삼 분말을 첨가한 비열처리 두유의 경우, 저장 중 상층부의 입도 크기는 21.6±0.1 μm에서 38.5±3.1 μm와 투과도는 0.8±0.0%에서 58.1±0.1%로 각각 증가하였다. 인삼 분말을 첨가하지 않은 열처리 두유의 경우, 저장 중 상층부의 입도크기는 17.4±2.4 μm에서 1.1±0.0 μm로 감소하였고 투과도는 7.3±0.1에서 14.0±0.1로 증가하였다. 2% 인삼 분말을 첨가한 열처리 두유의 경우, 상층부의 입도 크기는 22.9±0.4-24.9±0.5 μm, 투과도는 1.0±0.0-4.3±0.1% 범위에서 일정한 값을 유지하여 가장 높은 저장 안정성을 나타내었다. 저장 중 하층부에서는 인삼 분말첨가와 열처리에 따른 입도크기와 투과도는 각각 12.5±0.9-24.5 μm와 0.3±0.0-7.3±0.1% 범위로써 유의적인 차이는 보이지 않았다.

Immobilization of anaerobic ammonium oxidizing bacteria has been studied to enhance the biomass retention of the slowly growing bacteria and the process stability. The purpose of this study was to compare the nitrogen removal efficiency of granular and immobilized anammox bacteria with poly vinyl alcohol and alginate. The specific anammox activity of the granular, homoginized and immobilized anammox bacteria were 0.016±0.0002 gN/gVSS/d, 0.011±0.001 gN/gVSS/d and 0.007±0.0005 gN/gVSS/d, respectively. Although the activity decreased to 43.7 % of the original one due to low pH and O2 exposure during the homogination and the immobilization, it was rapidly recovered within 7 days in the following continuous culture. When synthetic T-N concentrations of 100, 200, 400, 800 mg/L were fed, the immobilized anammox bacteria showed higher nitrogen removal efficiencies at all operational conditions than those of granular anammox bacteria. When the sludge retention time was shorten below 30.7 days and the reject water was fed, the nitrite removal efficiency of the granular anammox bacteria dropped to 8 % of the initial value, while that of the immobilized anammox bacteria was maintained over 95 % of the initial one. The immobilization with poly vinyl alcohol and alginate would be a feasible method to improve the performance and stability of the anammox process.

The process variables for the manufacture of translucent microemulsion prepared with 2-octyl dodecanol, 12-hydroxy stearic acid cholesteryl , POE(40)HCO and 1,3-butandiol were examined initially (primary emulsion) and following aging for three months. The techniques empolyed in this study were particle size, turbidity, interfacial tension and microfluidizer. Particle size analysis and turbidity measurement to evaluate the emulsion stability were used. It was concluded that the process of the emulsification was an important indicator of the stability of the translucent microemulsion. From the particle size and and turbidity measurement of translucent microemulsion, adding the surfactant to the oil phase before the emulsification was found to be the most important factor for the stability of emulsions. We found that interfacial tension of the adding the surfactant to the oil phase is lower than that of the adding the surfactant to aqueous phase. In spite of hydrophilic surfactant, adding the surfactant to aqueous phase produced inferior emulsion to that to oil phase.