교대로 운전되는 두 개의 UV/광촉매반응기로 구성된 폐가스 처리시스템에서의 광촉매의 비활성화 및 재생 특성

이은주 ( Eun Ju Lee ),정찬홍 ( Chan Hong Chung ),임광희 ( Kwang-hee Lim ) 한국화학공학회 2021 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.59 No.4

본 연구에서는 교대로 운전되는 두 개의 UV/광촉매 반응기로 구성된 폐가스 처리시스템의 운전단계와 단계별 광촉매의 비활성화의 상관관계를 사용된 광촉매에 대한 기기분석을 통하여 규명하였다. 선행연구[Lee와 Lim, Korean Chem. Eng. Research, 59(4), 574-583 (2021)]의 광촉매 반응기 시스템 운전에 사용되지 않은 광촉매를 담지한 다공성 SiO₂ 담체(A4), 1회 운전하는 동안 사용되고 재생을 경험하지 않은 광촉매를 담지한 다공성 SiO₂ 담체(A1), 2회 운전에 사용되고 1회 재생된 광촉매를 담지한 다공성 SiO₂ 담체(A2) 및 3회 운전에 사용되고 2회 재생된 광촉매를 담지한 다공성SiO₂ 담체(A3)와, 1차 재생(AD1) 또는 3차 재생(AD3)된 광촉매를 담지한 다공성 SiO₂ 담체에 대한 BET 분석, SEM, XPS, SEM-EDS 및 FTIR 분석 등을 수행하여, 광촉매를 담지한 다공성 SiO₂ 담체의 비활성화 및 재생 특성을 포함하는 특성 분석을 수행하였다. 그 결과로서, 3회 이상의 여러 번 재생을 수행하는 광촉매의 적정 재생 온도를 200℃ 미만으로 도출하였다. 이러한 광촉매의 적정 재생 온도는 BET 분석결과에서 도출된 기공에 흡착된 에탄올 산화분해 중간생성물의 대부분이 완전 분해가 되어 기공이 재생되는 재생 온도와 거의 일치하였다. 특히, XPS 분석 결과는, 선행 연구[Lee와 Lim, Korean Chem. Eng. Research, 59(4), 574-583 (2021)]에서 광촉매 반응기의 첫 번째 운전 후에 광촉매의 미세한 비활성화가 발생하였음을 나타내었다. 또한, XPS 분석 결과는, 선행연구[Lee와 Lim, Korean Chem. Eng. Research, 59(4), 574-583 (2021)]에서 광촉매 반응기의 두 번째 운전에서 비교적 큰 광촉매의 비활성화가 발생하여 첫번째 운전성능보다 약 5%만큼 못 미치는 에탄올과 황화수소 각각의 제거효율을 초래하였으나, 세 번째 운전에서의 에탄올과 황화수소의 제거효율은 두 번째 운전에서의 에탄올과 황화수소의 제거효율 실험 결과와 거의 비슷하였다는 연구 결과와 일치하였다. 한편, AD3를 사용하여 선행연구[Lee와 Lim, Korean Chem. Eng. Research, 59(4), 574-583 (2021)]에서와 같은 광촉매 반응기의 네 번째 운전을 수행할 것을 가정하면, 두 번째 운전에서보다 더 큰 광촉매의 비가역적 비활성화의 발생으로 인하여 에탄올과 황화수소 제거효율이 가장 크게 저하되리라 예상되었다. In this study, the correlation between operating stages of waste air-treating system composed of two alternatively-operating UV/photocatalytic reactors, and the deactivation of photocatalyst used in each operating stage, was investigated by instrumental analysis thereon. The repeated deactivation and subsequent re-generation of photocatalyst used in the waste air treating system of previous investigation performed by Lee and Lim (Korean Chem. Eng. Research, 59(4), 574-583(2021)), were characterized on virgin photocatalyst-carrying porous SiO₂ media (A4), used photocatalystcarrying porous SiO₂ media (A1, A2 and A3) collected from the corresponding photocatalytic reactor upon 1^st, 2^nd, and 3^rd run, respectively, regenerated photocatalyst-carrying porous SiO₂ media upon 1 time-run (AD1) and 3 times regenerated photocatalyst-carrying porous SiO₂ media upon 3 time-runs (AD3) by instrumental analysis including BET analysis, SEM, XPS, SEM-EDS and FT-IR. As a result, the proper regeneration-temperature for deactivated photocatalyst to be regenerated several times (more than 3 times), was suggested below 200℃. Such temperature of deactivated photocatalystregeneration was almost consistent to the one, according to BET analysis, at which tiny nano-pores blocked by adsorbed ethanol-oxidative and degraded intermediates (AEODI), were regenerated to be reopened through almost complete mineralization of AEODI. In particular, the results of XPS analysis indicated an incurrence of insignificant deactivation of photocatalysis upon 1^st run of UV/photocatalytic reactor (A or C) of the previous investigation. In addition, the results of XPS analysis were consistent with the experimental results of the previous investigation in that 1) deactivation of photocatalyst incurred during 2^nd run of the UV/photocatalytic reactor (A or C) resulted in decreased removal efficiency, by ca. 5% and 5%, of ethanol and hydrogen sulfide, respectively, compared with its 1^st run; 2) there was insignificant difference between the removal efficiencies of its 2^nd run and 3^rd run. Furthermore, the removal efficiencies of ethanol and hydrogen sulfide for hypothetical 4^th run of photocatalytic reactor in the previous investigation, using AD3, were expected to decrease, compared with its 3^rd run, by much more than those for 2^nd run in the previous investigation did, compared with its 1^st run.

Run-Length Coding과 Huffman Coding을 이용한 영상 압축기의 하드웨어 설계

이상진,김주현,이민우,강봉순,홍창희 東亞大學校附設 情報技術硏究所 2004 情報技術硏究所論文誌 Vol.12 No.1

In this paper, we modify Run-Length Coding(RLC) and Huffman Coding(HC) algorithm for use of image compression and design as a hardwired architecture. The algorithm of RLC and HC compresses different area of Multi-Resolution Analysis(MRA) that is represented by Discrete Wavelet Transform(DWT)[1-2]. RLC compressor and decompressor is simple so that is designed like a data-path flow. HC compressor's scheme is composed of 2 stage, the first one is generation of Huffman Tree. That needs many computations and times so that uses internal memory MACRO. The second one is making binary data using Huffman Tree. The decompressor of HC is also designed simply like that of RLC decompressor's data-path flow using Huffman Tree.

실드공법에 의한 도심지 터널의 해석

이홍주,김수석,진치섭 釜山大學校 都市問題硏究所 1997 都市硏究報 Vol.5 No.-

The use of underground space has been increased according as area of city has been limited by the urban concentration of population. So it was demanded to increasing tunnel, but this tunnel construction was made trouble in open cut method which has been used generally. Consequently, shield tunneling method is highlighting in urban civil. In the past decade soft clay shield tunneling technology have been improved to permit continuous support to the face of a tunnel. These advanced shield can be operated such that in initial heaving is created, this helps to decrease the inward soil movement into the tail void. In this paper, the measurement of slurry shield and EPB shield were used and two dimensional elasto-plastic programs EPSHILD developed for shield tunnel analysis were approved. The excavation steps corresponding with construction stages were settled and heaving load, load factors were considered. This study is based on the instantaneous settlement which is occured in the process of shield construction but not the secondary settlement by consolidation.

좌측흉수로 발현된 Boerhaave 증후군 1예

이준,변유미,조민근,조주연,원경준,김영대,박찬국,김만우,유재근,서홍주,이석기 朝鮮大學校 附設 醫學硏究所 2008 The Medical Journal of Chosun University Vol.33 No.2

구토 후 발생한 토혈을 주소로 내원한 환자에서 좌측 늑막 삼출 동반 시 식도 파열의 가능성을 고려하여 흉수 천자 및 지속적인 흉부 단순 촬영의 추적관찰이 필요하며 식도 파열이 배제된 후 환자의 생체 징후 및 토혈 양을 파악하여 내시경 검사 시기를 신중히 결정하는 것이 좋을 것으로 생각된다. 본 증례는 토혈을 주소로 내원하여 Mallory-Weiss 증후군 의심 하에 내시경을 통한 치료 시행 후 추적 관찰에 의해 진단된 Boerhaave 증후군을 경험하였기에 보고하는 바이다. Boerhaave's syndrome is a spontaneous perforation of the esophagus most commonly resulting from a sudden increase in intraesophageal pressure combined with negative intrathoracic pressure caused by straining or vomiting. Surgery should generally be performed within 24 hours because mortality approached 30 to 50 percent in which surgery was delayed. Therefore, early diagnosis and prompt surgical repair are critical for survival. We have experienced a case of Boerhaave's syndrome in a patient presenting with hematemesis with left pleural effusion without any signs or symptoms of pneumomediastinum or pneumothorax.

합성섬유를 혼입한 콘크리트의 강도 및 내구특성

홍창우,정영화,이주형,이정호 江原大學校 産業技術硏究所 1998 産業技術硏究 Vol.18 No.-

Concrete structures has been deteriorated by poor environment. This study was conducted to evaluate durability of concrete which are increasingly demanded recently. Therefore, the research of durability must be executed for application of Polypropylene fiber reinforced concrete real structures. Concrete durability properties incorporating Polypropylene fiber was performed with the variable of Fiber contents, Fiber type and Target strength, specimens were made and subjected to durability and strength tests. The results show that strength of concrete is increased the Fiber content increase, Mono-Filament fiber and Polypropylene fiber reinforced concrete makes improved durability properties.

만성 골수성 백혈병에 합병된 Progressive Multifocal Leukoencephalopathy 1례

이주헌,이재홍,이규형 대한신경과학회 1996 대한신경과학회지 Vol.14 No.1

바닥재 처리로 인한 수송 트레일러의 수직진동 감쇠 효과

이홍주,홍종호,김성엽 안성산업대학교 2002 論文集 Vol.34 No.-

This study was aimed to prevent the quality loss of agricultural products, which could be occurred by the vibrations of transporting trailer. The vibration absorption effect was measured and analyzed by mounting the polystyrene material on the bottom of trailer. The transporting trailer was tested with being mounted by the pear boxes up to fourth floor. The results of this study could be summarized as follows: 1. At low engine speed of 500rpm, the average vertical vibration level of the first floor boxes (lowest boxes) was reduced to almost half of the non-mounting system. And, at the fourth floor boxes (highest boxes), the vibration absorption effect was higher as about 10 times compared with the non-mounting system. 2. At standard engine speed of 1,000rpm, the average vertical vibration level of the first floor boxes was almost same as 0.005㎨ and 0.006㎨ respectively, but at the fourth floor boxes, the average vertical vibration was reduced to almost 60% of the non-mounting system.

Green 정리를 이용한 철근 콘크리트 단주해석

이홍주,박현재,진치섭 釜山大學校生産技術硏究所 1997 生産技術硏究所論文集 Vol.53 No.-

구조물 설계에서, 축하중과 2축 휨을 동시에 받는 기둥 설계를 자주 접하게 된다. 이러한 부재의 해석과 설계는, 모멘트 평형에 따른 여러 변수들의 값을 동시에 구하기 위하여 반복적인 작업이 필요하기 때문에 많은 시간을 요구한다. 본 연구에서는 축력과 2축 휨을 받는 철근 콘크리트 단주의 극한강도를 계산할 수 있는 컴퓨터 프로그램 COLI을 개발하였고, Green정리를 사용하여 임의 형상의 역학적 특성을 계산할 수 있는 수치 방법을 제시하였다. In structural design, columns subjected to combined axial load and biaxial bending are frequently encountered. The analysis and design of such members, are both time consuming and demanding because an iterative procedure is required in order to simultaneously evaluate a number of variables to achieve moment equilibrium. A computer program COLI is developed to compute the ultimate strength of reinforced concrete short columns subjected to combined compression and biaxial bending in this paper. A numerical procedure using Green's theorem is presented that calculates the mechanical properties of generic shapes.

주의력 결핍·과잉행동장애 소년의 자기공명 영상을 이용한 뇌량 및 측뇌실의 계량적 특성분석

이정섭,홍강의,김주한 大韓神經精神醫學會 1997 신경정신의학 Vol.36 No.2

By means of retrospecitive quantitative neuroanatomic imaging, the authors assessed the corpus callosum and the lateral venticle in the boys with attention deficit hyperactivity disorder(ADHD). The midsagittal cross-sectional area of the corpus callosum, divided into seven regions, and the axial ventricle-brain ratio were measured from magnetic resonance images of 18 boys with ADHD and 15 comparison boys. Two anterior regions, the genu and the rostral body, were found to have significantly smaller areas in the ADHD boys. There was no significant difference in ventricle-brain ratio between ADHD and comparison boys. This finding supports the theory of abnormal frontal lobe development in ADHD.

CARIES-METER를 이용한 치아우식 치료법의 기준에 관한 고찰

이지연,정홍주,백병주 全北大學校 齒醫學硏究所 1991 전북치대논문집 Vol.9 No.1

The purpose of this study was finding of criteria for exact diagnosis of initial caries and advanced caries lesions. 57 primary molar teeth & 43 permanent first molar teeth of 75 children that visited pedodontic department of chonbuk National University hospital were used for experiment. We compared with radiographic examination and suitable clinical treatment according to the extent of dental caries by using Caries Meter L. The obtained results were as follows. l. Concerning of the equality rate in the primary molars and permanent teeth, the case of comparing radiographic examination and clinical treatment method in the highest rate as 98.24% in the primary molars, whereas the case of comparing Caries Meter L and clinical treatment is the highest rate as 90.7% in the permanent teeth. 2. When comparing of the measurement in Caries Meter L and radiographic examination of primary molars, the concurrent rate on extent of dental caries was 100% in the enamel, 78% in the dentin and 50% in the pulp, the Pearson Correlation was r=0.864 and there were significant difference statistically as significant level α=0.01(P<0.01). 3. When comparing of the measurement in Caries Meter L and clinical treatment method of primary molars, the concurrent rate on extent of dental caries was 100% in the enamel, 80% in the dentin and 55.6% in the pulp, the Pearson Correlation was r=0.877 and there were significant difference statistically as significant level α= 0.01(P<0.01). 4. When comparing of the radiographic examination and clinical treatment method of primary molars, the concurrent rate was high as 90% in the pulp, the Pearson Correlation was r=0.982 and there were significant difference statistically as significant level α= 0.01(P<0.01). 5. When comparing of the measurement in Caries Meter L and radiographic examination of permanent teeth, the concurrent rate was 78% in the enamel, 66.7% in the dentin and 100% in the pulp, the Pearson Correlation was r=0.689 and there were significant difference statistically as significant level α=0.01(P<0.01). 6. When comparing of the measurement in Caries Meter L and clinical treatment method in the permanent teeth, the concurrent rate was 95.2% in the enamel, 85.7% in the dentin and 50% in the pulp, the Pearson Correlation was r=0.930 and there were significant difference statistically as significant level α=0.01(P<0.01). 7. When comparing of the radiographic examination and clinical treatment method in the permanent teeth, the concurrent rate was 74.1% in the enamel, 57.1% in the dentin and 50% in the pulp, the Pearson Correlation was r=0.681 and there were significant difference statistically as significant level α= 0.01(P<0.01).