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Non-Invasive Measurements of Thickness of Superconductor Films by Using Two-Resonant-Mode Rutile Resonator

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Chinese Physics Letters 2010年第8期27卷 203-206页

作者： jung ho Sang yang Woo Il LEE Jae Hun SOHN Jae Min ChoO Kee Nam KIM Bong Goo LEE Sang Young Department of Physics and Center for Wireless Transmission Technology Konkuk University Seoul 143-701 Korea Research Reactor Engineering Division Korea Atomic Energy Research Institute Daejeon 305-600 Korea

The film thickness should be known for extrazting the intrinsic surface resistance from the effective surface resistance as measured by using the dielectric resonator method. Thicknesses of 70 nm to 360 nm are measured for YBa2 Cu3 O7-δ films in a non-invasive way by using the two-resonant-mode dielectric resonator （TDR） method. A futile resonator with the respective resonant frequencies of 15.25-15.61 GHz and 15.10-15.37 GHz for the TE021 and the TE012 modes is used for this purpose. Differences between the values as measured by using the TDR technique and those measured by using a step profilometer appear to be less than 3%, which is smaller than the previous value of 5% as measured by using a 8. 6 GHz single-resonance mode futile resonator [Lee et al. J. Korean Phys. Soc. 54（2009）1619]. Merits of using the TDR method are discussed.

关键词： THICKNESS measurement SUPERCONDUCTORS THIN films RUTILE DIELECTRIC resonators PROFILOMETER ELECTRIC resistance SURFACES (Technology)

Synthesis of Co/SiO2 hybrid nanocatalyst via twisted Co3Si2O5（OH）4 nanosheets for high-temperature Fischer- Tropsch reaction

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Nano Research 2017年第3期10卷 1044-1055页

作者： Ji Chan Park Shin Wook Kang Jeong-Chul Kim Jae In Kwon Sanha Jang Geun Bae Rhim Mijong Kim Dong Hyun Chun ho-Tae Lee Heon jung Hyunjoon Song jung-li yang Clean Fuel Laboratory Korea Institute of Energy Research Daejeon 34129 Republic of Korea Advanced Energy Technology University of Science and Technology Daejeon 34713 Republic of Korea Center for Nanomaterials & Chemical Reactions Institute for Basic Science Daejeon 34141 Republic of Korea Department of Chemistry Korea Advanced Institute of Science and Technology Daejeon 34141 Republic of Korea

A cobalt-silica hybrid nanocatalyst bearing small cobalt particles of diameter -5 nm was prepared through a hydrothermal reaction and hydrogen reduction. The resulting material showed very high CO conversion （〉82%） and high hydrocarbon productivity （-1.0gHC·gcat^-1·h^-1 ） with high activity （-8.5 × 10^-5 ***^-1.s-1） in the Fischer-Tropsch synthesis reaction.

关键词： hybrid nanostructure Fischer-Tropsch synthesis thermal stability metal silicate hydroxide cobalt catalyst

In-situ formation of MOF derived mesoporous Co3N/amorphous N-doped carbon nanocubes as an efficient electrocatalytic oxygen evolution reaction

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Nano Research 2019年第7期12卷 1605-1611页

作者： Bong Kyun Kang Seo Young Im Jooyoung Lee Sung hoon Kwag Seok Bin Kwon SintayehuNibret Tiruneh Min-Jun Kim jung ho Kim Woo Seok yang Byungkwon Lim Dae ho Yoon Nano Materials and Components Research Center Korea Electronics Technology InstituteSeongnam 463-816Republic of Korea School of Advanced Materials Science and Engineering Sungkyunkwan University Suwon 440-746Republic of Korea Advanced Materials & Processing Center Institute for Advanced Engineering (IAE)Yongin 175-28Republic of Korea Australian Institute for Innovative Materials (AIIM) University of WollongongSquires WayNorth Wollongong NSW 2500Australia Department of Advanced Materials Engineering for Information and Electronics Kyung Hee University1732 Deogyeong-daeroGiheung-guYongin-siGyeonggi-do17104Republic of Korea

The suitable materials,metal nitrides,are a promising class of electrocatalyst materials for a highly efficient oxygen evolution reaction (OER) because they exhibit superior intrinsic conductivity and have higher sustainability than oxide-based *** our knowledge,for the first time,we report a designable synthesis of three-dimensional (3D) and mesoporous Co3N@ amorphous N-doped carbon (AN-C) nanocubes (NCs) with well-controlled open-framework structures via monodispersed Co3[Co(CN)6]2 Prussian blue analogue (PBA) NC precursors using in situ nitridation and calcination ***3N@AN-C NCs (2 h) demonstrate better OER activity with a remarkably low Tafel plot (69.6 mV-dec-1),low overpotential of 280 mV at a current density of 10 ***,excellent cycling stability in alkaline electrolytes was exhibited without morphological changes and voltage elevations,superior to most reported hierarchical structures of transition-metal nitride *** presented strategy for synergy effects of metal-organic frameworks (MOFs)-derived transition-metal nitrides-carbon hybrid nanostructures provides prospects for developing high-performance and advanced electrocatalyst materials.

关键词： transition-metal nitride metal organic framework mesoporous oxygen evaluation reaction alkaline water electrolysis

Behavior of CaO and Calcium in pure Magnesium

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Rare Metals 2006年第z2期25卷 150-154页

作者： HA Seong-ho LEE Jin-Kyu JO Hyung-ho jung Seung-Boo KIM Shae K. Department of Advanced Material Engineering Sungkyunkwan University 300 Chunchun-dong Jangan-gu Suwon Gyunggi-do 440-746 KoreaAdvanced Material Division Korea Institute of Industrial Technology 7-47 Songdo-dong Yeonsu-gu Incheon 406-840 Korea Advanced Material Division Korea Institute of Industrial Technology 7-47 Songdo-dong Yeonsu-gu Incheon 406-840 Korea Department of Advanced Material Engineering Sungkyunkwan University 300 Chunchun-dong Jangan-gu Suwon Gyunggi-do 440-746 Korea

Mg alloys exhibit a number of good properties such as low density, good castability and high specific strength. however, molten Mg and Mg alloys are ignited without the melt protective gases during melting and casting process due to their high reactivity. The purpose of this study is to investigate effects of Ca and CaO on pure Mg through microstructure observation, ignition test and phase analysis. With increasing Ca and CaO contents, the ignition resistance of Ca or CaO added pure Mg is increased and the grains are refined. As results of XRD and EDS, CaO is reduced to Ca in CaO added pure Mg. Mg2Ca phase is formed even in 0.1 wt.%CaO added pure Mg by reduction mechanism, while Mg2Ca phase is formed over 1.35 wt.% Ca added pure Mg.

关键词： Mg CaO ignition resistance Mg2Ca phase

Optimal Age Replacement Policy with Replacement Occurrence While the Warranty is in Effect

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Journal of Shanghai Jiaotong university(Science) 2015年第3期20卷 374-379页

作者： PARK Minjae jung Ki Mun PARK Dong ho College of Business Administration Hongik University Department of Informational Statistics Kyungsung University Industry Academic Cooperation Foundation Hallym University

This study considers an age replacement policy(ARP) for a repairable product with an increasing failure rate with and without a product warranty. As for the warranty policy to consider in association with such an age replacement policy, we adapt a renewable minimal repair-replacement warrant(MRRW) policy with 2D factors of failure time of the product and its corresponding repair time. The expected cost rate during the life cycle of the product is utilized as a criterion to find the optimal policies for both with and without the product warranty. We determine the optimal replacement age that minimizes the objective function which evaluates the expected cost rate during the product cycle and investigate the impact of several factors on the optimal replacement age. The main objective of this study lies on the generalization of the classical age replacement policy to the situation where a renewable warranty depending on 2D factors is in effect. We present some interesting observations regarding the effect of relevant factors based on numerical analysis.

关键词： age replacement policy(ARP) expected cost rate failure times renewable minimal repairreplacement warranty(MRRW) warranty servicing times

Comparison of macular changes according to the etiology of optic neuritis:a cross-sectional study

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 686-692页

作者： Yeji Moon Sung-Min Kim Jae ho jung Department of Ophthalmology Asan Medical CenterUniversity of Ulsan College of MedicineSeoul 05505Republic of Korea Department of Neurology Seoul National University HospitalSeoul 03080Republic of Korea Department of Ophthalmology Seoul National University HospitalSeoul 03080Republic of Korea Department of Ophthalmology Seoul National University College of MedicineSeoul 03080Republic of Korea

AIM:To compare the macular structure including foveal thickness among patients with optic neuritis(ON)according to the etiology and to investigate the possible correlation between structural and visual outcomes METhoDS:In this retrospective cross-sectional study,the clinical data of patients with aquaporin-4 immunoglobulin G-related ON(AQP4 group,40 eyes),myelin oligodendrocyte glycoprotein IgG-related ON(MOG group,31 eyes),and multiple sclerosis-related ON(MS group,24 eyes)were *** retinal thickness of the foveal,parafoveal and perifoveal regions were *** acuity(VA),visual field index and mean deviation were measured as visual ***:The AQP4 group showed a significantly thinner fovea(226.4±13.4μm)relative to the MOG(236.8±14.0μm,P=0.015)and MS(238.9±14.3μm,P=0.007)*** thickness in the parafoveal area also was thinner in the AQP4 group,though the difference in perifoveal retinal thickness was not *** thickness was correlated with VA in the AQP4 group(coefficientρ=-0.418,P=0.014),but not in the MOG and MS groups(P=0.218 and P=0.138,respectively).There was no significant correlation between foveal thickness and visual field test in all three ***:The significant thinning in the fovea and parafoveal areas in the AQP4 group compared to the MOG and MS groups are ***,macular changes in AQP4-ON show a significant correlation with *** results provide the possibility that retinal structural damage could reflect functional damage in AQP4-ON,distinct from MOGON and MS-ON.

关键词： foveal thickness optic neuritis aquaporin-4 immunoglobulin myelin oligodendrocyte glycoprotein multiple sclerosis

Acute esophageal obstruction after ingestion of psyllium seed husk powder:A case report

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World Journal of Clinical Cases 2022年第7期10卷 2336-2340页

作者： Sujeong Shin jung ho Kim You ho Mun Han Sol Chung Department of Emergency Medicine Yeungnam University School of Medicine and College of MedicineDaegu 42415South Korea

BACKGROUND Bezoar is a mass of hardened external material found in the gastrointestinal(GI)*** may form anywhere in the GI tract,but esophageal bezoar is rare because of the short esophageal transit *** seed husk is an indigestible natural derivative that is widely used as an herbal ***,we report a case of acute esophageal obstruction caused by a bezoar after ingestion of psyllium seed husk *** SUMMARY A 76-year-old male with Parkinson’s disease visited the emergency department with swallowing difficulty approximately 10 h after ingesting psyllium seed husk *** began a few hours after ingestion and progressed to severe *** were no abnormal findings on simple ***,a computed tomography scan revealed an approximately 2.0 cm×2.5 cm mass located near the gastro-esophageal *** grinding,the mass was removed using an endoscopic capture *** bezoars may cause life-threatening *** with Parkinson’s disease may have esophageal motility dysfunction,which may increase esophageal transit *** our patient had Parkinson’s disease,this effect may have contributed to the formation of the *** Attention should be paid to using bulk-laxatives,and an appropriate specified regimen will be needed when marketed as a dietary supplement.

关键词： Bezoar Esophagus Obstruction Parkinson’s disease Psyllium Case report

Study on SCR De NO_x mechanism through in situ electrical conductivity measurements on V_2O_5-WO_3/TiO_2 catalysts

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Rare Metals 2006年第z2期25卷 77-83页

作者： HA Heon Phil jung Soon Hyo LEE Jun Yub hoNG Sung ho Metal Processing Research Center Korea Institute of Science and Technology Cheongryang Seoul 130-650 Republic of Korea Power Engineering Research Institute Korea Power Engineering Company Inc. 360-9 Mabuk-ri Guseong-eup Yongin-si Gyeonggi-do 449-713 Republic of Korea

V2O5-WO3/TiO2 catalysts were prepared by impregnation method and in situ electrical conductivity measurements were carried out to investigate the reaction mechanism for ammonia SCR (selective catalytic reduction) of NOx. The electrical conductivity change with ammonia supply and the increase of electrical conductivity were mainly caused by reduction of the labile surface oxygen. The electrical conductivity change of catalysts shows close relationship with the conversion rate of NOx. Variation of conversion rate in atmosphere without gaseous oxygen also supports that the labile lattice oxygen is indispensable in the initial stage of the de NOx reaction. These results suggest that the liable lattice oxygen acts decisive role in the de NOx mechanism. They also support that De NOx reaction occurs through the Eley-Rideal type mechanism. The amount of labile oxygen can be estimated from the measurement of electrical conductivity change for catalysts with ammonia supply.

关键词： De NOx selective catalytic reduction electrical conductivity lattice oxygen

Process simulation and economic analysis of reactor systems for perfluorinated compounds abatement without HF effluent

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Frontiers of Chemical Science and Engineering 2016年第4期10卷 526-533页

作者： Boreum Lee Sunggeun Lee ho Young jung Shin-Kun Ryi Hankwon Lim Department of Advanced Materials and Chemical Engineering Catholic University of Daegu Gyeongbuk 38430 Korea Department of Environment and Energy Engineering C-honnam National University-Gwangju 61186 Korea Korea Institute of Energy Research Daejeon 34129 Korea

New and efficient proposed to treat perfluorinated reactor systems were compounds via catalytic decomposition. One system has a single reactor （S-1）, and another has a series of reactors （S-2）. Both systems are capable of producing a valuable CaF2 and eliminating toxic HF effluent and their feasibility was studied at various temperatures with a commercial process simulator, Aspen HYSYS. They are better than the conventional system, and S-2 is better than S-1 in terms of CaF2 production, a required heat for the system, natural gas usage and CO2 emissions in a boiler, and energy consumption. Based on process simulation results, preliminary economic analysis shows that cost savings of 12.37% and 13.55% were obtained in S-2 at 589.6 and 621.4℃compared to S-1 at 700 and 750 ℃, respectively, for the same amount of CaF2 production.

关键词： perfluorinated compounds (PFCs) CF4 pro-cess simulation economic analysis