분리막 및 다양한 CO2 포집공정들의 연구에 있어, 경제성 평가는 각 공정들을 비교 분석하며 개발된 기술의 경제적 타당성을 검토하는데 중요한 역할을 한다. 본 연구에서는 분리막 기반의 CO2 포집공정에 대한 경제성 분석을 수행하여 그 결과를 살펴보았다. 분리막 공정의 전산모사와 최적화를 위하여 분리막 모델링 및 Aspen HYSYS®를 활용하였으며, 최적화 결과를 바탕으로 CAPEX 및 OPEX를 제시하여 분리막 공정의 경제성 평가를 진행하였다.

The carbon capture and storage (CCS) technology from industrial flue-gas has been an important environmental issue in these days. However, membrane process has a number of breakthrough-point to commercialization in scale-up. In this work, process optimization for high purity and high CO2 recovery with lower the capture cost has been investigated. Lab-made membrane pilot process using real flue gas has been also set up to derive industrial factor.

분리막 공정은 압력장치에 사용되는 전기 사용량이 많아 이를 줄이기 위한 다양한 공정 옵션이 연구되고 있다. 본 연구에서는 분리막 공정에서 막 모듈에 sweeping 기체를 permeate에 불어넣어 모듈의 구동력을 증가시키는 방법으로, 특별한 공정 장치 추가 없이도, 효율적인 CO2 분리가 되는 공정을 연구하였다. 분리막 공정은 주요 장치비용(분리막, 압축기 등)과 운영비용(전기, 스팀)을 평가 하였다. MATLABⓇ에서 분리막 모델을 개발하었으며, 분리막 공정에 가능한 모 든 구조들을 초구조로 경제성 평가 모델을 기준으로 평가되었다. 본 연구는 2014년도 정부(미래창조과학부)의 재원으로 (재)한국이산화탄소포집 및 처리연구개발센터의 지원을 받아 수행된 연구임(2014M1A8A1049305).

Membrane is a relatively new industrial gas separation technology and has been studied as an alternative CO2 capture technologies to amine absorption. Membrane processes have a merit such as low energy use, small footprint, no by-products formation, and simple operating condition. When applied to flue gas CO2 capture, low CO2 concentration and normal pressure of flue gas stream places a practical limits on the membrane operation. The up-to-date membranes should allow module performance to rise to levels practical for fossil-fuel power station use. In this talk, membrane module is being evaluated for flue gas treatment. Membrane processes using several membranes, which are now being studied under the R&D projects granted by KCRC, are investigated to capture CO2 from the simulated gas.

수처리에 있어 막여과 기술은 안전한 처리수질의 보장, 시스템의 집약화 및 자동화 등의 장점으로 인해 활발히 도입되고 있다. 하지만 핵심 기자재인 막 모듈의 설계나 전체 정수처리 공정의 안정성 부분에 대해서는 아직 기술개발의 여지가 남아 있다. 본 연구에서는 막여과 공정의 연속 운전에 있어서 막오염을 완화시키기 위한 목적으로 수행하는 물리적인 역세척의 효율 향상과 더불어 이 때 발생하는 역세배출수를 막 모듈 외부로 원활히 배출할 수 있도록 한 가압식 막여과 기술과, 이 때 발생한 가압식 막여과 배출수를 이중 구조로 구획된 침지 막조 이용하여 원활히 처리할 수 있는 침지식 막여과 기술을 결합하여 기존 기술에 비해 고회수율의 달성은 물론, 집약적이고 실용적인 2단 막여과 정수처리 시스템을 개발하고자 하였다.

Oral hyperpigmentation is common in patients older 40 years. But lesions in a newborn are unusual and congenital melanotic macule of the tongue has rarely been reported. A 2-month-old infant with 3 pigmented lesion on the right side of the dorsal tongue was evaluated. They were brown black but not homogeneous in color, smooth, nonblanchable, and nonpalpable, with irregular margins. We recommend excisional biopsy under general anesthesia because of possibility of malignancy, but parents refuse invasive procedure. On a following-up examination of the child at the age of 1 year, the pigmented lesions were unchanged. We report a case of congenital melanotic macules on the tongue and a review of literature about the lesion.

When working on electrical wiring and cable, Electrically insulated aerial work platforms must be used to prevent the electrocution hazards. Aerial work platforms with composition boom is able to increase the weight and height of the workspace due to the lightweight of boom. The aim of this paper is to clarify structural stability of 3 stage telescopic booms having an operator platform and an upper boom of composition(Fiber Reinforced Plastic) by comparing the general telescopic booms with steel material using computational analysis.

본 논문은 동역학의 새로운 변분이론인 확장 해밀턴 이론을 열 탄성과 공극 탄성에 적용하여 더욱 일반화하는 것에 그 주 요 목적이 있다. 이를 위해 열 탄성학에 대한 이론 적용이 우선적으로 검토되었고, 열 탄성-공극 탄성의 유사성을 바탕으로 공극 탄성에까지 그 이론이 확장되었으며, 각 경우에 대한 푸리에 변환을 통해 그 적정성을 확인하였다.

본 연구에서는 다래‘대성’과실의 수확 후 품질 보구력과 저장성 증진에 대한 효과를 살펴보고자 칼 슘-키토산을 수확 전후 처리 하였다. 수확 전 처리는 8월 20일, 25일, 28일 3회에 거쳐 과실에 살포 처리하였고, 수확 후 처리는 8월 31일 수확한 건전한 과실을 선별하여 침지 처리하였다. 처리한 과실은 1℃와 17℃ 온도 조건에 저장 하여 시기별로 가용성 고형물 함량, 산함량, 경도, 호흡률, 에틸렌발생량, 감모율을 조사하여 과실 품질을 평가하였다. 두 온도 조건에서 수확전후 칼슘-키토산 처리는 과피에 대 한 코팅효과에 의해 감모율 억제효과를 보였다. 17℃ 저장조건에서는 감모율 이외의 품질지표에서는 처 리간의 유의적인 차이가 없었으나, 1℃ 저장조건에서는 감모율 이외에도 경도와 호흡률에서 칼슘-키토 산 수확 전후처리가 과실 후숙을 억제하는 효과가 있음을 확인 하였다.

This research was conducted to evaluate quality changes in traditional Doenjang and manufactured Doenjang during a storage period of 8 weeks. Low-salt Doenjang and commercial Doenjang were purchased from different manufacturers and proximate analysis as well as changes in isoflavone, polyphenol, flavonoid contents of the samples were investigated using a mass spectrophotometer. The salinity of traditional Doenjang, low salt Doenjang, and commercial Doenjang were 13.2±1.15, 7.17±2.74, 10.67±0.35%, respectively and the salt concentrations of the soybean pastes did not change during storage. After 8 weeks at 35℃, chromatic values of all the paste samples decreased somewhat, with traditional Doenjang exhibiting fewer changes as compared to manufactured Doenjang. Amino acid nitrogen, acidity, microbial population all tended to increase with time, although some samples showed fluctuations during the test period. Moreover, the total isoflavone contents of traditional Doenjang increased with storage time while that of manufactured Doenjang tended to decrease. The isoflavone aglycone was shown to be the highest in traditional Doenjang, while isoflavone glycoside was abundant in manufactured Doenjang. Total flavonoid contents showed similar trends regardless of samples; initial contents of total flavonoid was 0.6 mg/g which increased to more than twice to 1.4 mg/g at the end of storage period. Composition profile of Doenjang extracts was analyzed using UPLC-Q-ToF

Using the ultrasonic pyrolysis method, spherical SiO2 powders were synthesized from aqueous SiO2 sol as a starting material. The effects of pyrolysis conditions such as reaction temperature, SiO2 sol concentration, and physical properties of precursor were investigated for the morphologies of the resulting SiO2 powders. The particle size, shape, and crystallite size of the synthesized SiO2 powders were demonstrated according to the pyrolysis conditions. Generally, the synthesized SiO2 particles were amorphous phase and showed spherical morphology with a smooth surface. It was revealed that increased crystallite size and decreased spherical SiO2 particle size were obtained with increases of the pyrolysis reaction temperature. Also, quantity of spherical SiO2 particles decreased with the decrease in the concentration and surface tension of the precursor.

SrAl2O4: Eu2+ and Dy3+ phosphorescent phosphors were synthesized using the polymerized complex method. Generally, phosphorescent phosphors synthesized by conventional solid state reaction show a micro-sized particle diameter; thus, this process is restricted to applications such as phosphorescent ink and paint. However, it is possible to synthesize homogeneous multi-component powders with fine particle diameter by wet process such as the polymerized complex method. The characteristics of SrAl2O4: Eu2+ and Dy3+ powders prepared by polymerized complex method with one and two step calcination processes were comparatively analyzed. Temperatures of organic material removal and crystallization were observed through TG-DTA analysis. The crystalline phase and crystallite size of the SrAl2O4: Eu2+ and Dy3+ phosphorescent phosphors were analyzed by XRD. Microstructures and afterglow characteristics of the SrAl2O4: Eu2+ and Dy3+ phosphors were measured by SEM and spectrofluorometry, respectively.

Geopolymers have many advantages over Portland cement, including energy efficiency, reduced greenhouse gas emissions, high strength at early age and improved thermal resistance. Alkali activated geopolymers made from waste materials such as fly ash or blast furnace slag are particularly advantageous because of their environmental sustainability and low cost. However, their durability and functionality remain subjects for further study. Geopolymer materials can be used in various applications such as fire and heat resistant fiber composites, sealants, concretes, ceramics, etc., depending on the chemical composition of the source materials and the activators. In this study, we investigated the thermal properties and microstructure of fly ash and blast furnace slag based geopolymers in order to develop eco-friendly construction materials with excellent energy efficiency, sound insulation properties and good heat resistance. With different curing times, specimens of various compositions were investigated in terms of compressive strength, X-ray diffraction, thermal property and microstructure. In addition, we investigated changes in X-ray diffraction and microstructure for geopolymers exposed to 1,000 oC heat.

The effect of PEMFC trapezoidal channel wall contact angle on water removal characteristics is investigated with the volume of fluid (VOF) method. Two different contact angles 60 and 90 degrees are selected. In the case of the side and top wall contact angle of 60 degrees, stable semi-spherical droplets move along the top wall slowly. In contrast, complex shaped droplets move along the lower edge in the case of 90 degrees. Moreover, it is shown that very complex interaction patterns between different droplets which introduced into the channel at different times.

The lattice Boltzmann method (LBM) is applied to study the behavior of liquid droplet inside a PEMFC gas channel. To validate the fluid-fluid interaction model, the relationship between the pressure jump across the interface and the bubble radius is investigated for a static bubble to confirm the Laplace’s law. To evaluate the fluid-solid interaction model, static contact angle is calculated by changing the interaction parameter. Also, a constant gravitational force is applied to study the temporal evolution of liquid droplet placed on the bottom wall in a three dimensional periodic channel.