• Journal of the Korean Electrochemical Society
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• v.16 no.1
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• pp.30-38
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• 2013

In this study, a catalyst slurry was prepared with a Pt/C catalyst, Nafion ionomer solution as a binder, an ionic liquid (IL) (1-butyl-3-methylimidazolium tetrafluoroborate), deionized water and ethanol as a solvent for the application to polymer electrolyte fuel cells (PEFCs) at high-temperatures. The effect of the IL in the electrode of each design was investigated by performing a cyclic voltammetry (CV) measurement. Electrodes with different IL distributions inside and on the surface of the catalyst electrode were examined. During the CV test, the electrochemical surface area (ESA) obtained for the Pt/C electrode without ILs gradually decreased owing to three mechanisms: Pt dissolution/redeposition, carbon corrosion, and place exchange. As the IL content increased in the electrode, an ESA decrement was observed because ILs leaked from the Nafion polymer in the electrode. In addition, the CVs under conditions simulating leakage of ILs from the electrode and electrolyte were evaluated. When the ILs leaked from the electrode, minor significant changes in the CV were observed. On the other hand, when the leakage of ILs originated from the electrolyte, the CVs showed different features. It was also observed that the ESA decreased significantly. Thus, leakage of ILs from the polymer electrolyte caused a performance loss for the PEFCs by reducing the ESA. As a result, greater entrapment stability of ILs in the polymer matrix is needed to improve electrode performance.

• Journal of the Korean Chemical Society
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• v.56 no.6
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• pp.731-738
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• 2012

The purpose of this study is to analyze the understandings of science high school students on the conception of chemical cell in relation to chemical equilibrium from the microscopic viewpoint at molecular level through questionnaires and follow-up interviews. The results show that they have high understandings on the chemical equilibrium states in the electrochemical cell and on the redox reaction taking place simultaneously when a metal electrode is immersed in the metal ion solution. However, they do not fully comprehend the development of electrical potential difference, electron movement, electrode potential measurement in the half-cells, and calculation of the net cell voltage between anode and cathode in the chemical cell because of difficulties in the microscopic understanding the interaction on the interface at the electrode and the electrolyte solution.

• Journal of Radiation Protection and Research
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• v.14 no.2
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• pp.23-29
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• 1989

A Lucas cell was established and calibrated by using the double layer tube standard radon source. The calibration factors were 0.031$\pm$0.002 (pCi/l)/(cph/Cell) at room temperature, and 0.029$\pm$0.001 (pCi/l)/(cph/Cell) at $50^{\circ}C$. Radon and its daughters concentrations were measured in a room air for the demonstrating purpose. The concentrations of 222 Rn, $^{218}Po,\;224\;Pb,\;and\;^{214}Bi$ were 0.87, 0.53, 0.35 and 0.26 pCi/l. The total eqilibrium factor was around 0.40 and the WL is $3.33{\times}10^{-3}$, resulting in 30 mrem/yr at this place.

• Journal of Digital Convergence
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• v.12 no.11
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• pp.265-272
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• 2014

This study suggests a system for preventing and coping with diverse industrial accidents available for taking place in the industrial field by designing a context-aware system of the solar cell equipment with the use of multi-sensor. It installs multi-sensor in the surrounding and major positions of the solar cell equipment, acquires data on the surrounding situations and solar cell equipment from this device, and then save it into the local memory and transmits it to the server. The saved data recognizes a situation based on the context-aware algorithm and judges depending on the perceived result. An administrator comes to have environment available for monitoring the status on the production field and equipments with real time according to the judged outcome through the context-aware algorithm. The context-aware system in the industrial field, which is put today in the ubiquitous environment, will become a service of offering appropriate information for dealing with industrial accidents through real-time inspection.

• Journal of Korean Society of Forest Science
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• v.3 no.1
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• pp.1-4
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• 1963

Present experiment has been carried out in order to make clear the abnormalities of the female gametophyte formation and its relation to fertility, using the short-style of F. koreana, the results of which are summarized as follows : (1) Anatropous ovule has single integument with thick cell-layer and tiny nucellus consisting of nucella-epidermis and megaspore mother cell. (2) Meiotic division of megaspore mother cell takes place around middle or latter part of March, while that of microspore mother cell occurs from the end of September to the beginning of October. (3) Megaspore mother cell stage is long, and ranges from October to March next year. (4) Formation of mature embryo sac is not completed until the beginning of May, approximately one month after blooming. (5) Normal embryo sac is rare, most of the nucellus being devoid of embryo sac.

• Korean Journal of Agricultural Science
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• v.47 no.2
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• pp.361-373
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• 2020

Integrins such as lymphocyte function-associated antigen -1 (LFA-1) have an essential role in T cell immunity. Integrin activation, namely, the transition from the inactive conformation to the active one, takes place when an intracellular signal is generated by specific receptors such as T cell receptors (TCRs) and chemokine receptors in T cells. In an effort to explore the molecular mechanisms underlying the TCR-mediated LFA-1 activation, we had previously established a high-throughput cell-based assay and screened a chemical library deposited in the National Institute of Health in the United States. As a result, several hits had been isolated including HIKS-1 (Benzo[b]thiophene-3-carboxylic acid, 2-[3-[(2-carboxyphenyl) thio]-2,5-dioxo-1-pyrrolinyl]-4,5,6,7-tetrahydro-,3-ethyl ester). In an attempt to reveal the mode of action of HIKS-1, in this study, we did drug affinity responsive target stability (DARTS) assay finding that HIKS-1 interacted with the IQ motif containing GTPase activating protein 1 (IQGAP1), a 189 kDa multidomain scaffold protein critically involved in various signaling mechanisms. Furthermore, the cellular thermal shift assay (CETSA) provided compelling evidence that HIKS-1 also interacted with IQGAP1 in vivo. Taken together, it can be concluded that HIKS-1 interferes with the TCR-mediated LFA-1 activation by interacting with IQGAP1 and thereby disrupting the signaling pathway for LFA-1 activation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1291-1296
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• 2006

This study was performed to determine the antimutagenic and anticancer effects of Fagopyrum esculentum Moenech noodles (FEMN) extracts using Ames test and cytotoxicity, respectively. FEMN made buckwheat wet noodles (BWN), buckwheat extruded noodles (BEN) and buckwheat dehydrated noodles (BDN) by 60% buckwheat flour and 70% buckwheat flour. The inhibitory effects of FEMN extracts on cell proliferation in A549, Hep3B, MCF-7, AGS and HeLa were investigated by SRB assay. The cytotoxic effects of FEMN against the cell lines with human lung carcinoma (A549), human gastric carcinoma (AGS), human hepatocellular carcinoma (Hep3B), human cervical adenocarcinoma (HeLa) and human breast adenocarcinoma (MCF-7) were inhibited with the increase of the extract concentration. The treatment of 1.0 mg/mL FEMN of 60% BEN extracts showed strong cytotoxicities of 74.7%, 75.3% and 70.5% against AGS, A549 and HeLa, respectively. The inhibition rate of 70% BWN of FEMN extracts in the S. Typhimurium TA100 strain showed 41% against the mutagenesis induced by MNNG. The inhibition rate of 70% BEN of FEMN extracts in the S. Typhimurium TA98 strain showed 45% against the mutagenesis induced by 4NQO.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.6
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• pp.749-758
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• 2011

The present work explores the performance and operation limit of electrodialysis cell for HI concentration in sulfur iodine thermochemical hydrogen production process, For this purpose, the electrodialysis cell was assembled with Nafion 117 as a PEM membrane and two activated carbon papers as the electrodes. HIx solution was prepared with composition of HI: $I_2$: $H_2O$ = 1: 0.5~2.5: 5.2 in molar ratio. The cell and its peripheral apparatus were placed in the specially designed convective oven in order to uniformly maintain the operation temperature. As operation temperature increased, the amount of water transport from anode to cathode increased, thus reducing HI molarity in catholyte. Meanwhile, the current efficiency was constant as about 90 %, irrespective of temperature change. The cell voltage increased with initial $I_2$ mole ratio as well as anolyte to catholyte mole ratio. Moreover the cell voltage overshot took place within 10 h cell operation, which is due to the $I_2$ precipitation inside the cell. From the analysis of $I_2$ mole ratio in the anolyte, it is noted that operation limit (in $I_2$ mole ratio) of the electrodialysis cell, arising from was measured to be 3.2, which is much lower than bulk solubility limit of 4.7.

• Journal of the Korean Society of Radiology
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• v.8 no.3
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• pp.123-136
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• 2014

In this paper, we study to classify molecular imaging and applications to predict future. Molecular imaging in vivo at the cellular level and the molecular level changes taking place to be imaged, that is molecular cell biology and imaging technology combined with the development of the new field. Molecular imaging is used fluorescence, bioluminescence, SPECT, PET, MRI, Ultrasound and other imaging technologies. That is applied to monitoring of gene therapy, cell tracking and monitoring of cell therapy, antibody imaging, drug development, molecular interaction picture, the near-infrared fluorescence imaging of cancer using fluorescence, bacteria using tumor-targeting imaging, therapeutic early assessment, prediction and therapy. The future of molecular imaging would be developed through fused interdisciplinary research and mutual cooperation, which molecular cell biology, genetics, chemistry, physics, computer science, biomedical engineering, nuclear medicine, radiology, clinical medicine, etc. The advent of molecular imaging will be possible to early diagnosis and personalized treatment of disease in the future.

• The Korean Journal of Food And Nutrition
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• v.28 no.3
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• pp.404-414
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• 2015

Taurine is one of the most abundant free ${\beta}$-amino acids in the human body that accounts for 0.1% of the human body weight. It has a sulfonic acid group in place of the more common carboxylic acid group. Mollusks and meat are the major dietary source of taurine, and mother's milks also include high levels of this amino acid. The leukocytes, heart, muscle, retina, kidney, bone, and brain contain more taurine than other organs. Furthermore, taurine can be synthesized in the brain and liver from cysteine. There are no side effects of excessive taurine intake in humans; however, in case of taurine deficiency, retinal abnormalities, reduced plasma taurine concentration, and other abnormalities may occur. Taurine enters the cell via a cell membrane receptor. It is excreted in the urine (approximately 95%) and feces (approximately 5%). Taurine has a number of features and functions, including conjugation with bile acid, reduction of blood cholesterol and triglyceride levels, promotion of neuron cell differentiation and growth, antioxidant effects, maintenance of cell membrane stability, retinal development, energy generation, depressant effects, regulation of calcium level, muscle contraction and relaxation, bone formation, anti-inflammatory effects, anti-cancer and anti-atherogenic effects, and osmotic pressure control. However, the properties, functions, and effects of taurine require further studies in future.