• Journal of Oriental Medical Thermology
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• v.2 no.1
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• pp.35-42
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• 2003

Objective : This study is to examine the interrelationship between Infertility with hypothalamic-pituitary gland disorders and Face temperature by D.I.T.I. Methods : Sample group is the 50 women who were diagnosed as P.C.O.S. or FSH,LH trouble or hyper-prolactinemia or anovulation or oligo-ovulation. Control group is the 50 women who have not P.C.O.S. & FSH.LH trouble & hyper-prolactinemia & anovulation or oligo-ovulation, who have normal menstural cycle and success in pregnancy after treatment. Both group came at Conmaul Oriental Hospital Infertility Center, Seoul, Korea, from May, 2001 to Jan., 2003. They selected at random. We checked temperature of ${\ulcorner}S17{\lrcorner}\;{\ulcorner}SI18{\lrcorner}\;{\ulcorner}TE17{\lrcorner}\;{\ulcorner}HN-3{\lrcorner}$ and gained differences of Rt. check point and Lt. check point, and then compared mean ${\Delta}T$ of sample group with that of control group. Conclusion : We gained results that mean ${\Delta}T$ of sample group is larger than that of control group at all check points. (p=0.000)

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.11
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• pp.1035-1040
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• 2003

High $T_{c}$ superconducting B $i_2$S $r_2$CaC $u_2$ $O_{8+d}$ (BSCCO2212) films were prepared by a metallorganic decomposition (MOD) method. The metal organic solution of BSCCO2212 was spin-coated on MgO (100) substrates at 3000 rpm for 1 min. To achieve a high critical current density, we controlled heat-treatment conditions and atmosphere. The films were annealed at temperature 75$0^{\circ}C$ ∼ 80$0^{\circ}C$ in $O_2$ or air. We obtained c-axis orientated BSCCO thin films on MgO substrates. The annealed sample at 77$0^{\circ}C$ with $O_2$ showed the critical temperature about 77 K and critical current denstity of 1.19 ${\times}$ 10$^{5}$ A/$\textrm{cm}^2$ about 13 K.

• Journal of the Korean Magnetics Society
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• v.16 no.1
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• pp.18-22
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• 2006

Effects of V substitution of Fe on the magnetic properties of $Fe_3O_4$ have been investigated by x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), conversion electron Mossbauer spectroscopy (CEMS), and vibrating sample magnetometry (VSM) measurements on sol-gel-grown films. XRD data indicates that the $V_xFe_{3-x}O_4$ films maintain cubic structure up to x=1.0 with little change of the lattice constant. Analyses on V 2p and Fe 2p levels of the XPS data indicate that V exist as $V^{3+}$ mostly in the $V_xFe_{3-x}O_4$ films with the density of $V^{2+}$ ions increasing with increasing V content. Analyses on the CEMS data indicate that $V^{3+}$ ions substitute tetrahedral $Fe^{3+}$ sites mostly, while $V^{2+}$ ions octahedral $Fe^{2+}$ sites. Results of room-temperature VSM measurements on the films reveal that the saturation magnetization for the x=0.14 sample is larger than that of $Fe_3O_4$, while it becomes smaller than that of $Fe_3O_4$ for $x{\geq}0.5$. The coercivity of the $V_xFe_{3-x}O_4$ films is found to increase with x, attributed to the increase of anisotropy by the substitution of $V^{2+}(d^3)$ ions into the octahedral sites.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.1134-1136
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• 1993

The mean grain size of sample decreases with increasing the addition of $Al_2O_3$ in the basic composition of YIG. It is mean that the addition of $Al_2O_3$ is helpless the development of magnetic properties in YIG garnet, considering the relation of ${\mu}{\propto}D^{1/3}$. To increase addition of $Al_2O_3$ decreased the area of hysterisis loop. It is known that the addition of $Al_2O_3$ is help the development of magnetic properties in YIG garnet, considering the relation of loss component factor and the area of hysterisis loop. As a results, sample with the addition of $Al_2O_3$ 0.5 mol % among the fabricated samples is must effective in the magnetic properties of YIG Garnet.

• Korean Journal of Chemical Engineering
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• v.35 no.11
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• pp.2321-2326
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• 2018

We evaluated the optimal conditions for fluidization of nickel oxide (NiO) and its reduction into high-purity Ni during hydrogen reduction in a laboratory-scale fluidized bed reactor. A comparative study was performed through structural shape analysis using scanning electron microscopy (SEM); variance in pressure drop, minimum fluidization velocity, terminal velocity, reduction rate, and mass loss were assessed at temperatures ranging from 400 to $600^{\circ}C$ and at 20, 40, and 60 min in reaction time. We estimated the sample weight with most active fluidization to be 200 g based on the bed diameter of the fluidized bed reactor and height of the stocked material. The optimal conditions for NiO hydrogen reduction were found to be height of sample H to the internal fluidized bed reactor diameter D was H/D=1, reaction temperature of $550^{\circ}C$, reaction time of 60 min, superficial gas velocity of 0.011 m/s, and pressure drop of 77 Pa during fluidization. We determined the best operating conditions for the NiO hydrogen reduction process based on these findings.

• Progress in Superconductivity
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• v.3 no.1
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• pp.36-40
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• 2001

We have studied vortex dynamics in$ Bi_2$$Sr_2$$CaCu_2$O$_{8}$single crystals of unirradiated and irradiated samples by using 100 $\times$ $100\mu\textrm{m}^2$Hall sensor. Doses equivalent magnetic fields are 20 G, 100 G and 1 kG. In the magnetization measurement, a second magnetization peak (SMP) was observed in unirradiated, 20 G dose and 100 G dose samples in contrast to 1 kG dose sample. In the unirradiated sample, the SMP was observed in the range of 18 K ~ 35 K and the amplitude of the SMP decreased with increasing temperature. With increase of the irradiation dose, temperature region and sharpness of the SMP were reduced. In the magnetic relaxation measurement, we observed that the normalized relaxation rate S decreased with increasing the irradiation dose. Our results suggest that the vortex dynamics is not greatly affected by low-density columnar defects.s.

• Journal of the Korean institute of surface engineering
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• v.40 no.1
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• pp.39-43
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• 2007

The pure CrN powders oxidized to $Cr_2O_3$ noticeably above $850^{\circ}C$ in air. When these powders were sintered into bulk samples at $1500^{\circ}C$ under 40 atm of $N_2$ pressure, the CrN phase partly changed into the $Cr_2N$ phase, owing to the partial loss of nitrogen from CrN. When the bulk sample was heated at $1000-1200^{\circ}C$ for 100 hr under vacuum, the CrN phase also progressively changed into $Cr_2N$. At the same time, a relatively thin $Cr_2O_3$ layer formed on the bulk sample due to the reaction of chromium with residual oxygen in vacuum.

• Food Science and Preservation
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• v.1 no.1
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• pp.21-27
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• 1994

For the purpose of improving microbiolgical quality of carrot powder, which is being used as minor ingredients of convenience foods, comparative influence of Υ-irradiation and ethylene oxide(E.O) fumigation was investigated with emphasis on sterilizating effect and physicochemical propertied Carrot powder sample was contaminated with thermophiles 4.0$\times$103/g, acid tolerant bacteria 3.7$\times$103/g and coliforms 1.6$\times$102/g, respectively. And thus sanitation process was required. E.O fumigation in commercial practice was not enough to destroy thermophilic bacteria, while Υ-irradiation at below 5 kGy could reduce all microorganisms up to undectected levels. Radiosensitivity(D10) of thermophiles was shown to be 2.25 kGy. The applicable dose of irradiation to the improvement of microbiological quality showed insignificant influences on the physicochemical quality of the sample.

• Journal of Magnetics
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• v.1 no.2
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• pp.57-59
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• 1996

The YBa$_2$Cu$_3$O6+xstructures have been fluorinated by a gas phase exchange technique, and 19F NMR was used to identify the structural fluorine. Magnetic susceptibility measurements showed that the fluorination turned a marginally nonsuperconducting sample into a 40 K superconductor, as well as that it raised the onset of the superconducting transition of the 60 K superconductor YBa$_2$Cu$_3$O6.7 to about 100 K.

• Natural Product Sciences
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• v.24 no.4
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• pp.288-292
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• 2018

High-performance countercurrent chromatography (HPCCC) coupled with reversed-phase highperformance liquid chromatography (RP-HPLC) method was developed to isolate dihydrophaseic acid 3'-O-${\beta}$-D-glucopyranoside (DHPAG) from the extract of Nelumbo nucifera seeds. Enriched DHPAG sample (2.3 g) was separated by HPCCC using ethyl acetate/n-butanol/water system (6:4:10, v/v/v, normal-phase mode, flow rate: 4.0 mL/min) to give 23.1 mg of DHPAG with purity of 88.7%. Further preparative RP-HPLC experiment gave pure DHPAG (16.3 mg, purity > 98%). The current study demonstrates that utilization of CCC method maximizes the isolation efficiency compared with that of solid-based conventional column chromatography.