Corrosion Behavior of Hastelloy C-276 for Carbon-anode-based Oxide Reduction Applications

Jeon, Min Ku,Kim, Sung-Wook,Choi, Eun-Young Korean Radioactive Waste Society 2020 방사성폐기물학회지 Vol.18 No.3

The corrosion behavior of Hastelloy C-276 was investigated to identify its applicability for carbon-anode-based oxide reduction (OR), in which Cl₂ and O₂ are simultaneously evolved at the anode. Under a 30 mL·min^-1 Cl₂ + 170 mL·min^-1 Ar flow, the corrosion rate was less than 1 g·m^-2·h^-1 up to 500℃, whereas the rate increased exponentially from 500 to 700℃. The effects of the Cl₂-O₂ composition on the corrosion rate at flow rates of 30 mL·min^-1 Cl₂, 20 mL·min^-1 Cl₂ + 10 mL·min^-1 O₂, and 10 mL·min^-1 Cl₂ + 20 mL·min^-1 O₂ with a constant 170 mL·min^-1 Ar flow rate at 600℃ was analyzed. Based on the data from an 8 h reaction, the fastest corrosion rate was observed for the 20 mL·min^-1 Cl₂ + 10 mL·min^-1 O₂ case, followed by 30 mL·min^-1 Cl₂ and 10 mL·min^-1 Cl₂ + 20 mL·min^-1 O₂. The effects of the chlorine flow rate on the corrosion rate were negligible within the 5-30 mL·min^-1 range. A surface morphology analysis revealed the formation of vertical scratches in specimens that reacted under the Cl₂-O₂ mixed gas condition.

Comparative evaluation of the algorithms for parametric mapping of the novel myocardial PET imaging agent ¹⁸ F-FPTP

Kim, Ji Who,Seo, Seongho,Kim, Hyeon Sik,Kim, Dong-Yeon,Lee, Ho-Young,Kang, Keon Wook,Lee, Dong Soo,Bom, Hee-Seung,Min, Jung-Joon,Lee, Jae Sung Springer Japan 2017 Annals of nuclear medicine Vol.31 No.6

<P><B>Objective</B></P><P>(<SUP>18</SUP>F-fluoropentyl)triphenylphosphonium salt (<SUP>18</SUP>F-FPTP) is a new promising myocardial PET imaging tracer. It shows high accumulation in cardiomyocytes and rapid clearance from liver. We performed compartmental analysis of <SUP>18</SUP>F-FPTP PET images in rat and evaluated two linear analyses: linear least-squares (LLS) and a basis function method (BFM) for generating parametric images. The minimum dynamic scan duration for kinetic analysis was also investigated and computer simulation undertaken.</P><P><B>Methods</B></P><P><SUP>18</SUP>F-FPTP dynamic PET (18 min) and CT images were acquired from rats with myocardial infarction (MI) (<I>n</I> = 12). Regions of interest (ROIs) were on the left ventricle, normal myocardium, and MI region. Two-compartment (<I>K</I><SUB>1</SUB> and <I>k</I><SUB>2</SUB>; 2C2P) and three-compartment (<I>K</I><SUB>1</SUB>–<I>k</I><SUB>3</SUB>; 3C3P) models with irreversible uptake were compared for goodness-of-fit. Partial volume and spillover correction terms (<I>V</I><SUB><I>a</I></SUB> and <I>α</I> = 1 − <I>V</I><SUB><I>a</I></SUB>) were also incorporated. LLS and BFM were applied to ROI- and voxel-based kinetic parameter estimations. Results were compared with the standard ROI-based nonlinear least-squares (NLS) results of the corresponding compartment model. A simulation explored statistical properties of the estimation methods.</P><P><B>Results</B></P><P>The 2C2P model was most suitable for describing <SUP>18</SUP>F-FPTP kinetics. Average <I>K</I><SUB>1</SUB>, <I>k</I><SUB>2</SUB>, and <I>V</I><SUB><I>a</I></SUB> values were, respectively, 6.8 (ml/min/g), 1.1 (min<SUP>−1</SUP>), and 0.44 in normal myocardium and 1.4 (ml/min/g), 1.1 (min<SUP>−1</SUP>), and 0.32, in MI tissue. Ten minutes of data was sufficient for the estimation. LLS and BFM estimations correlated well with NLS values for the ROI level (<I>K</I><SUB>1</SUB>: <I>y</I> = 1.06<I>x</I> + 0.13, <I>r</I><SUP><I>2</I></SUP> = 0.96 and <I>y</I> = 1.13<I>x</I> + 0.08, <I>r</I><SUP><I>2</I></SUP> = 0.97) and voxel level (<I>K</I><SUB>1</SUB>: <I>y</I> = 1.22<I>x</I> − 0.30, <I>r</I><SUP><I>2</I></SUP> = 0.90 and <I>y</I> = 1.26<I>x</I> + 0.00, <I>r</I><SUP><I>2</I></SUP> = 0.92). Regional distribution of kinetic parametric images (<I>αK</I><SUB>1</SUB>, <I>K</I><SUB>1</SUB>, <I>k</I><SUB>2</SUB>, <I>V</I><SUB>a</SUB>) was physiologically relevant. LLS and BFM showed more robust characteristics than NLS in the simulation.</P><P><B>Conclusions</B></P><P>Fast kinetics and highly specific uptake of <SUP>18</SUP>F-FPTP by myocardium enabled quantitative analysis with the 2C2P model using only the initial 10 min of data. LLS and BFM were feasible for estimating voxel-wise parameters. These two methods will be useful for quantitative evaluation of <SUP>18</SUP>F-FPTP distribution in myocardium and in further studies with different conditions, disease models, and species.</P><P><B>Electronic supplementary material</B></P><P>The online version of this article (doi:10.1007/s12149-017-1171-6) contains supplementary material, which is available to authorized users.</P>

Corrosion Behavior of Inconel X-750 for Carbon Anode Oxide Reduction Application

Jeon, Min Ku,Kim, Sung-Wook,Lee, Sang-Kwon,Choi, Eun-Young Korean Radioactive Waste Society 2020 방사성폐기물학회지 Vol.18 No.3

The corrosion behavior of the Inconel X-750 alloy was investigated for its potential application under a Cl₂-O₂ mixed gas flow in an Ar atmosphere. The corrosion rate was found to be negligible at temperatures up to 400℃ under a flow rate of 30 mL·min^-1 Cl₂ + 170 mL·min^-1 Ar, whereas an exponential increase was observed in the corrosion rate at temperatures greater than 500℃. The suppression of the corrosion reaction due to the presence of O₂ was verified experimentally at flow rates of 30 mL·min^-1 Cl₂ (4.96 g·m^-2·h^-1), 20 mL·min^-1 Cl₂ + 10 mL·min^-1 O₂ (2.02 g·m^-2 ·h^-1), and 10 mL·min^-1 Cl₂ + 20 mL·min^-1 O₂ (1.34 g·m^-2·h^-1) under a constant Ar flow rate of 170 mL·min^-1 at 600℃ for 8 h. The surface morphology analysis results revealed that porous surfaces with tunnel-type holes were produced under the Cl₂-O₂ mixed-gas condition. Furthermore, the effects of the Cl₂ flow rate on the corrosion rate were investigated, indicating that its impact was negligible within the range of 5-30 mL·min^-1 Cl₂ at 600℃.

The relationship between aerobic capacity and the recruitment of activated sweat gland density with passive heating

( Tae Wook Kim ),( Jong Hyuck Kim ),( Nam Eun Bae ),( Hyung Seok Seo ),( Young Soo Baik ),( Jeong Beom Lee ),( Hun Mo Yang ),( Young Ki Min ) 한국운동영양학회 2012 Journal of exercise nutrition & biochemistry Vol.16 No.4

This study investigated whether the recruitment of activated sweat gland density during passive heating [immersion of the lower body into hot water, 41℃ for 30 min (PH), room temperature 23 ± 0.5℃ with 60 ± 3% relative humidity] is different in endurance-trained (Trainee), compared with that of untrained subjects (Control), as indicated by VO2max. Eight trainees and seven control female subjects (38.31 ± 4.91 ml·kg-1·min-1 and 31.8 ± 0.92 ml·kg-1·min-1, respectively, p < 0.01) were similar on all other physical characteristics. To compare the changes between the trainees and controls, serum cortisol and prolactin (PRL), tympanic temperature (TYMP), local activated sweat gland density (L-ASGD) and the mean whole body sweat loss volume (M-WBSLV) changes were measured after PH. The cortisol was significantly higher (p < 0.05) and the PRL tended to be higher in the Trainee than in the Control. The TYMP increased more in the Trainee than in the Control (p < 0.001). The L-ASGD showed a higher tendency in the Trainee than in the Control, there was a significant difference in the mean activated sweat gland density (p < 0.01) and the L-ASGD was significantly correlated with the VO2max (p < 0.001). The M-WBSLV was significantly higher in the Trainee (p < 0.001) and significantly correlated with the VO2max (p < 0.001). The results suggest that in humans, a high aerobic capacity is associated with a greater recruitment of activated sweat glands, whole body loss of volume and TYMP. Therefore, the decline in the heat loss responses, due to decrease in maximal oxygen consumption, may be masked by repeated endurance exercise training.

임상 증상이 심하지 않은 심낭 삼출 환자의 장기 추적 결과

배장호,김기식,강미숙,남명희,김미정,김민수,김기영,님창욱,김윤년,김권배,정시전,김여희 대한순환기학회 1999 Korean Circulation Journal Vol.29 No.7

정상상피세포(HaCat)와 자궁경부 암세포(SiHa)에서 GeneFishing^(TM) PCR technique을 이용한 유전자 발현의 변화

김병훈,배수미,서민제,김용완,이정웅,김용욱,이준모,남궁성은,김종국,안웅식 대한부인종양 콜포스코피학회 2003 Journal of Gynecologic Oncology Vol.14 No.4

목적 : 본 실험의 목적은 정상상피 세포와 자궁경부 암세포 사이에서 유전자의 발현 차이를 조사하였다. 연구 방법 : 정상상피 세포(HaCat)와 자궁암 세포(SiHa)를 사용하였으며, 두 세포 간에 유전자 발현 차이를 GeneFish^(TM) PCR을 이용하여 알아보았으며, BLAST serach를 통해 분석하였다. 결과 : 정상상피 세포와 자궁암 세포 비교 결과, 자궁암 세포에서 S1-2-2와 S5-1을 포함한 25개의 유전자가 발현이 증가하였고, 24개의 유전자가 감소하였다. 결론 : GeneFishing^(TM) PCR기법은 유전자의 발현 변화를 확인하는데 있어서 아주 민감하고 효과적인 방법이다. 우리는 정상상피 세포와 자궁경부 암세포에서 다르게 발현하는 유전자를 찾을 수 있었고, 앞으로는, 종양의 발생과 진행과정에 관여하는 유전자를 더 탐지하고 해당 유전자의 기능을 연구할 필요가 있다고 생각된다. Objective : The purpose of this study is investigated the differentially expressed genes between normal and cervical cancer cell line. Methods : We used normal human keratinocyte (HaCaT) as a control and HPV-16 positive cervical cancer (SiHa) cell line. Two cell lines were studied differential expressed genes by using GeneFishing^(TM) PCR and analyzed with BLAST search. Results : As compared with normal, cervical cancer cell line was showed 25 up-regulated genes including the S1-2-2, S5-1 and 24 down-regulated genes. Conclusion : GeneFish^(TM) PCR test is very sensitive and effective method for detection of changed gene expression. We could search differentially expressed genes between normal and cervical cancer cell line. In the future, we need to research various genes function to participate in the process of tumor development and progression.

Facile Synthesis and Radioiodine Labeling of Hypericin

Kim, Sang-Wook,Park, Jeong-Hoon,Yang, Seung-Dae,Hur, Min-Goo,Kim, Yu-Seok,Chai, Jong-Seo,Kim, Young-Soon,Yu, Kook-Hyun Korean Chemical Society 2004 Bulletin of the Korean Chemical Society Vol.25 No.8

Hypericin (1,3,4,6,8,13-hexahydroxy-10,11-dimethylphenanthro[1,10,9,8-opqra]perylene-7,14-dione), an antidepressant which is also known to be a potent protein kinase C (PKC) inhibitor was synthesized as a precursor for radioiodine labeling via two step reactions. Malignant glioma cells express higher PKC activity compared to untransformed glial cell. Here we report the synthesis and radioiodine labeling of hypericin as a potential brain tumor imaging radiopharmaceutical. The reference compound, 2-iodohypericin, and its radiolabelled analogues, 2-[$^{123}I$]iodohypericin and 2-[$^{124}I$]iodohypericin have been prepared by the reaction of hypericin with NaI or [$^{123}I$]NaI or [$^{124}I$]NaI. The labeling yield was 60-65% for each analogue and the optimal reaction time was 10 min. The purification and isolation of the labelled products were achieved by a reversed-phase HPLC.

Photovoltaic properties of TiO2-based solar cells with sodium ethanesulfonate-modified photoelectrodes

Kim, Sun Jie,Kim, Wook Hyun,Lee, Chang-Hyun,Kim, Hwa-Min,Kang, Cheon Su,Han, Yoon Soo Informa UK (TaylorFrancis) 2017 MOLECULAR CRYSTALS AND LIQUID CRYSTALS - Vol.651 No.1

<P>Effects of sodium ethanesulfonate (SES) adsorbed on photoelectrode surface on the performance of dye-sensitized solar cells (DSSCs) was investigated. SES-modified photoelectrode was prepared by soaking the TiO2 film to an aqueous SES solution for 20 min. The DSSC with SES-modified TiO2 layer showed an increase in open circuit voltage (V-oc), short circuit current (J(sc)) and fill factor (FF), resulting in a power conversion efficiency of 11.20%, compared to that of reference device with bare TiO2 (10.21%). Electrochemical impedance spectroscopy and open circuit voltage decay measurements revealed that the SES modification of TiO2 surface led to a longer electron lifetime by the suppression of the interfacial charge recombination between photo-injected electrons and I-3(-) ions, resulting in an increase in J(sc) and V-oc, compared with those of a reference device without surface modification.</P>

Ultra-fast bull's eye-like self-healing using CNT heater

Kim, Heejin,Yarin, Alexander L.,Lee, Min Wook Butterworth Scientific Ltd. etc. 2019 Polymer Vol.180 No.-

<P><B>Abstract</B></P> <P>In the present work, carbon nanotubes (CNTs) are dispersed in the polydimethylsiloxane (PDMS) matrix and used as an embedded heating source. The electrically conductive CNT layer provides the Joule heating of the released healing materials into cracks. This accelerates the release and polymerization (self-healing) rates. It is demonstrated that with this modification the healing process, which originally required at least 24 h, is shortened to only 10 min. In addition, it is proved that this approach works very well even in the low-temperature environment, where otherwise, the healing efficiency is low because of the high viscosity of the healing agents and reduced rate of the polymerization reaction. The bull's eye-like geometry proposed in this work can be replicated to protect large areas.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The healing time is reduced remarkably from 24 h to 10 min with an improved toughness. </LI> <LI> This approach works very well even in the ice water bath (T~1 °C). </LI> <LI> The bull's eye-like unit geometry is replicable to protect large areas. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

베체트병 환자에서 Azathioprine으로 유발된 급성 췌장염 1례

김기향,권민정,김동기,김애란,김윤정,박지훈,이영태,박보민,김동욱 白中央醫療院 2005 仁濟醫學 Vol.26 No.1

Although many drug are thought capable of initiating acute pancreatitis, following azathioprine administration represents the 5% incidence by far the highest recorded incidence to date. We report a 35-year-old male who developed acute pancreatitis in the course of treatment with azathioprine for Behcet's disease. He was admitted due to abdominal pain, diarrhea, and fever for 10 days. Serum amylase and lipase levels were 510U/L and 3702U/L respectively. The abdominal CT scan revealed diffuse enlargement of the pancreas. There was no history of alcohol use or gall bladder disease. We considered drugs, especially azathioprine, as the cause of acute pancreatitis. We diagnosed it as acute pancreatitis. The patient was treated conservatively with hydration and analgesics. The symptom subsided within four days. Five days later, azathioprine was resumed. And the patient complained of abdominal pain. The elevated levels of serum amylase and lipase confirmed the recurrence of pancreatitis. His symptom subsided when azathioprine intake the stopped, and the serum amylase and lipase levels returned to normal level within five days.