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.-

A Study on the Physical Properties of Mineral Hydrate Insulation Material Mixed with Basalt Fiber

Park, Jae-Wan,Chu, Yong-Sik,Seo, Sung-Kwan,Jeong, Jae-Hyen The Korean Ceramic Society 2016 한국세라믹학회지 Vol.53 No.1

Mineral hydrate is a new insulation material that compensates for the defects of existing materials. Mineral hydrate is made of inorganic ingredients; therefore, it is nonflammable. The porous structure of mineral hydrate makes the material lightweight and insulating. Mineral hydrate insulation and similar products have been studied and manufactured in Korea and abroad. However, these insulation materials need to improve in terms of strength. In this study, basalt fiber was used to enhance the strength. In order to observe the property changes, compressive strength, heat conductivity, and specific gravity were measured and XRD pattern analysis was performed. These tests confirmed that basalt fiber was effective at improving the strength and lowering the heat conductivity of mineral hydrate insulation.

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>

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

Effect of local anesthesia on pulpal blood flow in mechanically stimulated teeth

Chu, Wan-Sik,Park, Seung-Ho,Ahn, Dong-Kuk,Kim, Sung-Kyo 大韓齒科保存學會 2006 Restorative Dentistry & Endodontics Vol.31 No.4

에피네프린을 함유한 국소마취제가 치수혈류량에 미치는 영향을 관찰하고, 이 국소마취가 와동 형성에 의해 야기되는 치수의 혈류변화에 미치는 영향을 평가하고자 전신마취된 아홉 마리의 고양이 견치에서 1 : 100,000 에피네프린이 함유된 2% 리도카인 용액으로의 국소 침윤마취 전후 및 와동형성 전후의 치수혈류를 laser Doppler flowmetry (Periflux4001, Perimed Co., Sweden)를 사용하여 측정하고 paired t-test로 통계분석하였다. 상아질 와동의 형성은 치수혈류의 현저한 증가를 초래하였다 (p < 0.05). 에피네트린을 함유한 리도카인의 침윤마취는 치수혈류를 유의하게 감소시켰다 (p < 0.05). 국소마취한 치아에서는 마취도지 않은 치아에 비해 와동형성시 유의하게 적은 치수혈류의 증가를 나타내었다 (p < 0.05). 따라서 본 연구에서는 혈관수축제를 포함한 국소마취가 와동 형성에 의해 초래되는 혈류량의 증가를 효과적으로 억제 할 수 있음을 보여주고 있다. The aims of the study were to evaluate the effect of epinephrine-containing local anesthetics on pulpal blood flow (PBF) and to investigate its effect on cavity preparation-induced PBF change. PBF was recorded using a laser Doppler flowmeter (Perimed Co., Sweden) from canines of nine cats under general anesthesia before and after injection of local anesthetics and after cavity preparation. 2% lidocaine hydrochloride with 1 : 100,000 epinephrine was administered by local infiltration given apical to the mandibular canine at the vestibular area and the same volume of isotonic saline was injected on the contralateral tooth as a control. A round carbide bur was operated at slow speed with isotonic saline flushing to grind spherical cavities with increasing depth through the enamel and into the dentin on both teeth. The obtained data was analyzed with paired t-test. Cavity preparation caused significant increase of PBF (n = 9, p < 0.05). Local infiltration of lidocaine with epinephrine resulted in decreases of PBF (n = 9, p < 0.05), whereas there was no significant change of PBF with the physiologic saline as a control. Cavity preparation on tooth anesthetized with lidocaine with epinephrine caused significantly less increase of PBF than in control tooth (p < 0.05). Therefore, the result of the present study demonstrates that local infiltration of 2% lidocaine with 1 : 100,000 epinephrine effectively reduces PBF increase caused by cavity preparation. 〔J Kor Acad Cons Dent 31(4):257-262, 2006〕

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

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.