Chemical-Looping Combustion을 위한 금속산화물 매체들의 산화 환원 반응특성

이진배,송영욱,박주식,최상일,김영호,양현수 忠南大學校 産業技術硏究所 2003 산업기술연구논문집 Vol.18 No.2

Chemical-looping combustion has been focused as a very promising combustion technology from the viewpoint of high energy efficiency, easy separation of CO_(2) and no formation of NO_(x). The key of this combustion technology is to develop oxygen carrier mediums with high oxygen capacity, and high machanical and thermal stability. In this study, various kinds of mediums were prepared by the combination of active metal oxides, such as NiO, CoO, Fe_(2)O_(3) or NiO-Fe_(2)O_(3), with YSZ(yttria stabilized zirconia) as a binder. The redox reactions on the mediums were also carried out by using the thermogravimetric reactor. The redox reaction rates on a NiO/YSZ medium were found to be most superior in comparison with those of other mediums. In addition, durability of the medium was also found to be appropriate for UC. For the purpose of high redox reaction rates, the optimum reaction temperatures of reduction and oxidation on a NiO/YSZ medium were observed as 600℃ and l000℃, respectively.

공기 다단공급식 미분탄 버너의 NOx 저감 특성

박주식(Chu Sik Park),김성완(Sung Won Kim),최상일(Snag Il Choi) 한국연소학회 2001 KOSCOSYMPOSIUM논문집 Vol.- No.-

Inhibitory Effects of Lactobacillus plantarum Q180 on Lipid Accumulation in HepG2 Cells

Chu, Jaeryang,Joung, Hyunchae,Kim, Byung-Kook,Choi, In-Suk,Park, Tae-Sik The Korean Society of Food and Nutrition 2019 韓國食品營養學會誌 Vol.32 No.6

Recently, the prevalence of hyperlipidemia has been increasing, and consequently, the need to identify safe and effective treatments to control this chronic disease has also increased. The beneficial effects of probiotics have been revealed by several studies over the past few years, including their effects on hypertriglyceridemia. However, the mechanisms of action of probiotics are still unclear. The anti-obesity effects of Lactobacillus plantarum Q180 on lipid accumulation have already been demonstrated using an in vitro HepG2 cell model, and therefore, we investigated its efficacy and mechanism of action. Lipid accumulation was induced in HepG2 cells by palmitic acid treatment and then the cells were incubated with L. plantarum Q180 lysate or supernatant to investigate changes in lipid accumulation and expression of lipid metabolism-related genes. The results showed that the L. plantarum Q180-treated group exhibited significantly lower levels of lipid accumulation and mRNA expression of lipid synthesis- and adipogenesis-related genes than the palmitic acid-treated group did. These results indicate that L. plantarum Q180 may contribute to alleviating hypertriglyceridemia by inhibiting lipid synthesis.

COVID-19 in a 16-Year-Old Adolescent With Mucopolysaccharidosis Type II: Case Report and Review of Literature

Park So Yun,Kim Heung Sik,Chu Mi Ae,Chung Myeong-Hee,Kang Seokjin 대한소아감염학회 2022 Pediatric Infection and Vaccine Vol.29 No.2

Coronavirus disease 2019 (COVID-19) in patients with underlying diseases, is associated with high infection and mortality rates, which may result in acute respiratory distress syndrome and death. Mucopolysaccharidosis (MPS) type II is a progressive metabolic disorder that stems from cellular accumulation of the glycosaminoglycans, heparan, and dermatan sulfate. Upper and lower airway obstruction and restrictive pulmonary diseases are common complaints of patients with MPS, and respiratory infections of bacterial or viral origin could result in fatal outcomes. We report a case of COVID-19 in a 16-year-old adolescent with MPS type II, who had been treated with idursulfase since 5 years of age. Prior to infection, the patient’s clinical history included developmental delays, abdominal distension, snoring, and facial dysmorphism. His primary complaints at the time of admission included rhinorrhea, cough, and sputum without fever or increased oxygen demand. His heart rate, respiratory rate, and oxygen saturation were within the normal biological reference intervals, and chest radiography revealed no signs of pneumonia. Consequently, supportive therapy and quarantine were recommended. The patient experienced an uneventful course of COVID-19 despite underlying MPS type II, which may be the result of an unfavorable host cell environment and changes in expression patterns of proteins involved in interactions with viral proteins. Moreover, elevated serum heparan sulfate in patients with MPS may compete with cell surface heparan sulfate, which is essential for successful interaction between the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein and the host cell surface, thereby protecting against intracellular penetration by SARS-CoV-2. 코로나바이러스감염증-19 (COVID-19)의 임상 양상은 무증상부터 급성 호흡곤란 증후군에 이르기까지 다양하다. 점액 다당류증(mucopolysaccharidosis) 2형은 글라이코스아미노글라이칸(glycosaminoglycan)의 일종인 헤파란 황산염(heparan sulfate)과 더마탄 황산염(dermatan sulfate)의 분해를 촉매하는 효소 결핍에 의해 상기 물질이 리소좀(lysosome)에 축적되는 질환으로 전신 침범, 특히 호흡기침범을 특징으로 한다. 따라서 박테리아나 바이러스에 의한 호흡기 감염은 예후에 치명적일 수 있다. 현재 점액 다당류증 환자에서 제 2형 중증급성호흡기증후군 코로나 바이러스(SARS-CoV-2) 감염 후의 임상 양상에 대한 보고는 매우 드물고, 이에 점액 다당류증 2형으로 효소대체요법을 받고 있던 환자에서 상기 바이러스 감염 후의 임상 양상에 대해 보고하고 관련 문헌에 대해 고찰하고자 한다. 16세 남아로 가족간 전파로 코로나바이러스감염증이 발생하였다. 콧물, 기침, 가래 등 호흡기 증상이 관찰되었다. 발열이나 산소요구도 증가는 없었으며 심박수, 호흡수, 산소 포화도는 정상 범위였고 혈액검사결과에서 백혈구 감소증이 관찰되었다. 흉부 방사선 사진에서 폐렴 소견은 보이지 않았다. 보존적 치료와 격리만으로 증상이 호전되었다. 경미한 임상 양상의 원인으로 전구 물질의 축적으로 인해 바이러스에게 불리한 숙주의 세포 환경, 바이러스와의 상호작용에 관여하는 단백질을 암호화하는 유전자 발현의 특정방향으로의 변화가 제시되고 있다. 또한 점액 다당류증 환자에서 증가된 혈청 헤파란 황산염이 SARS-CoV-2 스파이크 단백질과 숙주 세포의 상호작용에 필수적인 세포 표면의 헤파란 황산염과 경쟁하여 SARS-CoV-2의 세포 내 침투로부터 보호한다는 가설도 있다. 향후 더 많은 사례를 통해 점액 다당류증 등의 리소좀 축적질환에서 코로나바이러스감염증의 발현 양상에 대한 연구가 필요하다.

Detection and genetic characterization of Lawsonia intracellularis from swine in Korea

Chu, Jia-Qi,Hu, Xu-Min,Kim, Myung-Cheol,Park, Chang-Sik,Jun, Moo-Hyung The Korean Society of Veterinary Service 2010 韓國家畜衛生學會誌 Vol.33 No.3

A total of 191 samples collected from the commercial swine farms located in Chungnam province were investigated by PCR to estimate the prevalence of Lawsonia (L.) intracellularis infection. In the group of the pigs with proliferative enteritis, 14 (93.3%) of 15 intestinal samples and 12 (80.0%) of 15 feces were positive in PCR. In contrast, a relatively low positive rate (18.0%, 29 of 161 samples) was determined in the group of normal healthy pigs. The group of pigs over 120 days showed the highest positive rates (26.8%, 15 of 56 samples). In the comparison of the sequences of 210bp for species specific fragments and 301bp for outer membrane protein, the isolates (L1. L2) showed almost 100% identity with the reference L. intracellularis (L08049, USA). For the sequences of partial 16s rDNA, the homologies among the 5 isolates (L1-L5) were 97.4% to 99.3%, and those of 5 sequences (L1-L5) versus 5 overseas reference strains of L. intracellularis ranged from 98.6% to 99.8%. In the comparison of the nucleotide sequences among 5 isolates and other species in Desulfovibrionales showed 82.4 to 99.5% identities. The 5 isolates shared relatively low identities (76.9% to 84.4%) with the species of alpha-proteobacteria. In phylogenetic analysis based on the 16s rDNA sequences, all of the 5 isolates (L1-L5) were located in the same branch with the strains of L. intracellularis that were previously isolated from the pigs in USA and China. Seven strains of Desulfovibrio sp. were clustered in the neighboring branches, whereas alpha and gamma Proteobacteria showed distant relationship with L. intracellularis strains. The present findings suggest that L. intracellularis infection is endemic in the swine farms in the regions, and that the domestic isolates maintained very limited genetic variation.

Controlled Drug Delivery of Hollow Mesostructured Materials

Park, Sung Soo,Moorthy, M. Santha,Chu, Sang-Wook,Dong, Fuping,Guo, Wanping,Ha, Chang-Sik American Scientific Publishers 2013 Advanced porous materials Vol.1 No.1

3-D architecture between indium tin oxide nano-rods and a solution processed CuInGaS₂ absorber layer for thin film solar cells

Chu, Van Ben,Kim, Chan Sik,Park, Gi Soon,Lee, Young Ki,Hwang, Yun Jeong,Do, Young Rag,Min, Byoung Koun Elsevier S.A. 2017 Thin Solid Films Vol.636 No.-

<P><B>Abstract</B></P> <P>The performance of thin film solar cells can be significantly enhanced by efficient light management. In this study, we integrated one-dimensional indium tin oxide (ITO) nanorods into CuInGaS<SUB>2</SUB> (CIGS) films to fabricate 3-D nanostructured thin film solar cells. 400, 600, and 1000nm ITO nanorod substrates were used as back contact electrodes. Precursor solutions of Cu, In, and Ga with and without binder materials were prepared to fill the gaps between the ITO nanorods and increase the thickness of the CIGS films, respectively. Heat treatments both in air and in H<SUB>2</SUB>S were applied to form polycrystalline CIGS films while minimizing carbon impurities. 3-D nanostructured solar cell devices with Al,Ni/AZO/i-ZnO/CdS/CIGS/ITO nanorods/Glass structures were fabricated and characterized. Under standard irradiation conditions, the 600nm ITO nanorod solar device was found to have the maximum power conversion efficiency of 6%. This superior efficiency may be attributed to enhanced light absorption and complete gap filling.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Solution processed CIGS films were fabricated on ITO nanorod substrates. </LI> <LI> The optimal 3-D CIGS solar cell achieved the highest efficiency of 6.03%. </LI> <LI> The 3-D CIGS solar cell showed ~77% improvement in efficiency over a planar one. </LI> </UL> </P>

Facile synthesis of mesoporous carbon nitrides using the incipient wetness method and the application as hydrogen adsorbent

Park, Sung Soo,Chu, Sang-Wook,Xue, Chunfeng,Zhao, Dongyuan,Ha, Chang-Sik Royal Society of Chemistry 2011 Journal of materials chemistry Vol.21 No.29

<P>Highly nitrogen-enriched mesoporous carbon nitride materials with 2-dimensional (2-D) (2D-meso-CN) and 3-dimensional (3-D) mesostructures (3D-meso-CN) were synthesized using mesoporous silica as a hard template and cyanamide as a precursor <I>via</I> the incipient wetness process without using any solvent. The materials were characterized by small-angle X-ray scattering (SAXS), X-ray diffraction (XRD), and transmission electron microscopy (TEM) for the mesostructure analysis, N<SUB>2</SUB> adsorption–desorption isotherms for surface area and pore size distribution, and X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared (FT-IR) spectroscopy for the composition analysis of frameworks. The mesoporous carbon nitride replicas have graphitic-like stacking of carbon nitride sheets in mesopore walls. The N/C ratio of the mesoporous carbon nitride replicas is 1.13 after the carbonization at 550 °C for 3 h. 2D-meso-CN and 3D-meso-CN have the BET surface area of 361 and 343 m<SUP>2</SUP> g<SUP>−1</SUP>, large pore volume of 0.50 and 0.67 cm<SUP>3</SUP> g<SUP>−1</SUP>, and pore diameter of 27.8 Å (for 2D-meso-CN), 24.5 and 80.3 Å (for 3D-meso-CN), respectively. It was found that the 3D-meso-CN has higher capacity of hydrogen uptake of 0.25 wt% than the pure mesoporous carbon FDU-15 (0.16 wt%) at 50 bar under room temperature (298 K).</P> <P>Graphic Abstract</P><P>Highly nitrogen-enriched mesoporous carbon nitride materials with 2-dimensional (2-D) (2D-meso-CN) and 3-dimensional (3-D) mesostructures (3D-meso-CN) were synthesized using mesoporous silica as a hard template and cyanamide as a precursor <I>via</I> the incipient wetness process without using any solvent. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c1jm10849b'> </P>

Detection and Genetic Characterization of Swine Hepatitis E Virus in Swine Herds in Korea

Chu, Jiaqi,Chae, Mi-Kyung,Kim, Ji-Young,Park, Chang-Sik,Kim, Myung-Cheol,Jun, Moo-Hyung 충남대학교 형질전환복제돼지연구센터 2007 논문집 Vol. No.10

Hydrogen Production during the Desulfurization of Petroleum Cokes with Molten Caustic Leaching

Si Hyun Lee 한국화학공학회 1998 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.36 No.1