• Journal of the Korean Electrochemical Society
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• v.12 no.1
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• pp.34-39
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• 2009

In this study, a needle coke was oxidized in a mixture of dilute nitric acid and sodium chlorate ($NaClO_3$) solutions and followed by heat treatment. The samples were analyzed with using XRD, FESEM, elemental analyzer, BET, and Raman spectroscopy. Double layer capacitance was measured with the charge and discharge measurements. The consisting layers of the needle coke were expanded to single phase showing only (001) diffraction peak by the acid treatment for 24 hours. The oxidized coke returned to a graphite structure appearing (002) peak after heat treatment above $200^{\circ}C$. The structure returned could be more easily accessible to the ions by the first charge, and improve the double layer capacitance at the second charge. The two-electorde cell from acid treated coke and $300^{\circ}C$ heat treatment exhibited the maximum capacitances of 32.1 F/g and 29.5 F/ml at the potential of $0{\sim}2.5\;V$.

• Journal of The Korean Astronomical Society
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• v.47 no.6
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• pp.319-325
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• 2014

We map two molecular clouds located in the exact anticenter region emitting in the (J = 1-0) transition of $^{12}CO$ and $^{13}CO$ using the 3-mm SIS mixer receiver on the 14-m radio telescope at Taeduk Radio Astronomy Observatory. The target clouds with anomalous velocities of $V_{LSR}{\sim}-20km\;s^{-1}$ are distinguished from other clouds in this direction. In addition, they are located in the interarm region between the Orion Arm and the Perseus Arm. Sizes of the clouds are estimated to be about 8.6 and 10.8 pc, respectively. The total mass is estimated to be about $4{\times}10^3$ $M_{\odot}$ using CO luminosity of the clouds. Several cores are detected, but no sign of star formation is found according to the IRAS point sources. Their larger linewidths, anomalous velocities, and their location at the interarm region make these clouds more distinguished, though their physical properties are similar to the dark clouds in the solar neighborhood in terms of mass and size.

• Progress in Medical Physics
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• v.7 no.2
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• pp.3-17
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• 1996

Dose compensators have been widely used in radiotherapy fields. But, few reliable verification methods have been reported. We have developed the verification method for the evaluation of the effect of dose compensator using exit beam dose profile. The exit beam dose profiles were measured with and without dose compensator. For this purpose X-Omat V films and lead screened cassettes are used and dose distibutions are compared. Phantom data are collected using CT simulator(Picker, AcQ Sim) and compensator information can be obtained from Render Plan 3-D planning System. Aluminum Compensators are generated by computer controlled milling machine. The real dose distribution in the phantom and the exit beam dose profile can be obtained simultaneously with the films in the phantom and the opposite site of the beam. Dose compensations effects for oblique beam, parallel opposing beam and inhomogeneous human phantom can be obtained using above tools. And we could simate those effects with exit beam dose profile using the method that we have developed in this study.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6369-6374
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• 2012

Vitexicarpin (3', 5-dihydroxy-3, 4', 6, 7-tetramethoxyflavone), a polymethoxyflavone isolated from Viticis Fructus (Vitex rotundifolia Linne fil.), has long been used as an anti-inflammatory herb in traditional Chinese medicine. It has also been reported that vitexicarpin can inhibit the growth of various cancer cells. However, there is no report elucidating its effect on human prostate carcinoma cells. The aim of the present study was to examine the apoptotic induction activity of vitexicarpin on PC-3 cells and molecular mechanisms involved. MTT studies showed that vitexicarpin dose-dependently inhibited growth of PC-3 cells with an $IC_{50}{\sim}28.8{\mu}M$. Hoechst 33258 staining further revealed that vitexicarpin induced apoptotic cell death. The effect of vitexicarpin on PC-3 cells apoptosis was tested using prodium iodide (PI)/Annexin V-FITC double staining and flow cytometry. The results indicated that vitexicarpin induction of apoptotic cell death in PC-3 cells was accompanied by cell cycle arrest in the G2/M phase. Furthermore, our study demonstrated that vitexicarpin induction of PC-3 cell apoptosis was associated with upregulation of the proapoptotic protein Bax, and downregulation of antiapoptotic protein Bcl-2, release of Cytochrome c from mitochondria and decrease in mitochondrial membrane potential. Our findings suggested that vitexicarpin may become a potential leading drug in the therapy of prostate carcinoma.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2503-2508
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• 2010

ZnO thin films were grown on Si or $SiO_2$/Si substrates, at growth temperatures ranging from 150 to $400^{\circ}C$, by atomic layer deposition (ALD) using diethylzinc and water. Despite the large band gap of 3.3 eV, the ALD ZnO films show high n-type conductivity, i.e. low resistivity in the order of $10^{-3}\;{\Omega}cm$. In order to understand the high conductivity of ALD ZnO films, the films were characterized with X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, elastic recoil detection, Rutherford backscattering, Photoluminescence, and Raman spectroscopy. In addition, the various analytical data of the ZnO films were compared with those of ZnO single crystal. According to our analytical data, metallic zinc plays an important role for the high conductivity in ALD ZnO films. Therefore when the metallic zinc was additionally oxidized with ozone by a modified ALD sequence, the resistivity of ZnO films could be adjusted in a range of $3.8{\times}10^{-3}\;{\sim}\;19.0\;{\Omega}cm$ depending on the exposure time of ozone.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.751-756
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• 2009

In the perspective of saving energy in buildings, the high performance of insulation and air tightness for improving the heating and the cooling efficiency, has brought economically positive effects. However, these building energy saving technologies cause the lack of ventilation, which is the direct cause of increasing the indoor contaminants, and is also very harmful to the residents, because they spend over 90% of their time indoors. Therefore, the ventilation is important to keep the indoor environment clean and it can also save the energy consumption. In this study, a HEPA type nano ceramic filter is designed as a passive ventilation system to collect airborne particles and to supply fresh outdoor air. The double layer filter, which has $30{\mu}m$ in diameter at the conditions of 10wt% of concentration and 3kV/cm of the electric intensity, is produced by electrospinning. The filtration coating technology is confirmed in the solution with $SiO_2$ nano particles using polymer nano fibers. Also double layer filters are coated with $SiO_2$ nano particles and finally the porous construction materials are made by sintering in the electric furnace at $200{\sim}1400^{\circ}C$. The efficiency is measured 96.67% at the particle size of $0.31{\mu}m$, which is slightly lower than HEPA filter. However the efficiency is turned out to be sufficient.

• 한국지구물리탐사학회:학술대회논문집
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• 2009.10a
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• pp.167-173
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• 2009

Bathymetry survey around the Baengnyeong-do was made by the Korea Hydrographic and Oceanographic Administration (KHOA), using the Simrad EM3000 Multi-Beam EchoSounder (MBES) mounted at the hull of the R/V Badaro 1. Sound velocity were monitored with frequent sound velocity profiler(SVP) casts during the acoustic measurements. The depth distribution and fluctuation of thermocline varied locally owing to the effect of several current flows such as Kuroshio current and Yellow sea coastal waters. These uncertainties cause the falling-off in accuracy of MBES results. In this paper, the bathymetry results will be presented and their accuracy will be discussed along with comparisons to the time and spatial variations in sound velocity profile.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.17 no.1
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• pp.55-65
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• 2004

Allergic rhinitis is an inflammation of the nasal mucosa which is triggered by an allergic reaction. When exposed to certain allergens, the IgE covered mast cells degranulate releasing inflammatory mediators and cytokines which results in a local inflammatory reaction. In many recent studies, molecular biological methods have been used to investigate the role of cytokines in pathogenesis and new therapeutic targets of allergic rhinitis. This experimental study was done to research effects of Sochungryong-tang. We have studied effect of mice on OVA-induced production of IL-4, IL-5, IFN-${\gamma}$ by murine splenocytes and effect of OVA-induced total IgE and OVA-specific IgE. The results were as follows; 1. In IL-4 study, Sochungryong-tang treated group was proved significant inhibitory effect(p〈0.005). 2. In IL-5 study, Sochungryong-tang treated group was proved significant inhibitory effect(p〈0.05). 3. In JFN-${\gamma}$ study, Sochungryong-tang treated group was proved significant inhibitory effect(p〈0.000001). 4. In Total IgE, Sochungryong-tang treated group was proved significant inhibitory effect(p〈0.000001). 5. In OVA-specific IgE, Sochungryong-tang treated group didn't showed significant inhibitory effect. Depending upon above results, it is considered that Sochungryong-tang has the inhibitory effect on the allergic rhinitis of mice and suggested that it could be used in relieving patients of the symptoms which are caused by allergic rhinitis.

• Journal of radiological science and technology
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• v.5 no.1
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• pp.55-62
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• 1982

Measurement of triiodothyronine($T_3$) concentration is useful for the diagnosic and treatment of thyroid gland diseases. Fundermental studies of measurement of $T_3$ concentration by radioimmunoassay were performed and values determined by commercially available kit, Coat-A-Count, Diagnostic Products Corporation. The optimal utilization of the radioimmunoassay in measuring $T_3$ concentrations is dependant not only on high quality performance of the assay, but also on their appropriate application to the clinical situation. These are several aspects that must be considered in every individual case. These include factors such as accurate pippeting in reagent preparation in the assay and through decanting to remove all visible moisture after incubation steps and so forth. In attempt to assess quality control of the radioimmunoassay of serum $T_3$, serum pools with high, medium, low $T_3$ concentrations were assayed for each of 5 samples. The results obtained with this study were as follow: 1. The coefficient of variation(C. V.) for the standard curve ranged between $0.2{\sim}3.5%$. 2. It was necessary that both incubation time and temperature should correctly be maintained all the in the assay performance. 3. The precison with the $T_3$ RIA procedure was good. 4. The measured values of serially diluted serum $T_3$ concentration with Ong/dl standard solution was proportional to the predicted values. However dilution curve of distilled water was not strait. 5. Calculated $T_3$ values of patient serum in normal group was $107.8{\pm}25.90ng/dl$ in male patient and $127.29{\pm}24.08ng/dl$ in female patient.

• Journal of the Korean Society for Nondestructive Testing
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• v.33 no.2
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• pp.212-218
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• 2013

A transfer method of neutron radiography was developed to measure the size of the end plug and a gap of an intact K102L-2, the irradiated fuel of a ballooned K174L-3, a ballooned and ruptured K98L-3. A typical irradiation time of 25 min. was determined to obtain a film density of between 2 and 3 of SR X-ray film with neutrons of $1.5{\times}10^{11}n{\cdot}cm^{-2}$. To validate and calibrate the results, a RISO fuel standard sample, Cd plate and ASTM-BPI/SI were used. An activated latent image formed in the $100{\mu}m$ Dy foil was subsequently transferred in a dark room for more than 8 hours to the SR film which is a maximum of three half-lives. Due to the L/D ratio an unsharpness of $9.82-14{\mu}m$ and a magnification of 1.0003 were given. After digitizing an image of SR film, the ballooning gap of the plug was discernible by an H/V filter of image processing. The gap size of the ballooned element, K174L-3, is equal to or greater than 1.2 mm. The development of a transfer method played a pivotal role in developing high burn-up of Wolsung and PWR nuclear fuel type.