• Proceedings of the KIEE Conference
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• 2007.11c
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• pp.138-140
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• 2007

$TiO_2-V_2O_5$ sol was fabricated using sol-gel method and $TiO_2-V_2O_5$ thin films were fabricated using dip-coating method. $V_2O_5$ sol was added 0.01mo1e, 0.03mo1e, 0.05mo1e into $TiO_2$ sol. Viscosity of sol increased fast from about 1,000 minutes and sol began gelation from about 10,000 minutes. As a results of crystalline properties, $V_2O_5$ peaks were not found despite of $V_2O_5$ addition. Endothermic reaction occurred due to evaporation of solvent and dissociation of OH at $80^{\circ}C$. Exothermic reaction occurred due to combustion and oxidation of solvent at $230^{\circ}C$, occurred to combustion and oxidation of alkyl group at $350^{\circ}C$. Thickness of thin films increased $0.1{\sim}0.25{\mu}m$ every a dipping.

• Journal of Chest Surgery
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• v.25 no.4
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• pp.364-382
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• 1992

In order to investigate the effect of intracellular cyclic GMP on the calcium channel, whole cell patch clamp technique with internal perfusion method was used in the single ventricular myocytes of the rabbit. Cyclic GMP, cGMP analogues, cAMP, isopernaline and forskolin were perfused into cells and their effects on the calcium current were analysed by applying depolarizing step pulse of 10 mV in amplitude for 200 msec from holding potential of -40 mV. Calcium currents usually activated from -30 mV and then reached a peak at +10 mV. Amplitude of the calcium current was standardized with membrane capacitance, 50 pF. Peak amplitude at +10 mV in control was -0.15 nA/50pF. When 100 mM cAMP was applied from the pipette, peak amplitude of calcium current increased to -0.32 nA and addition of 1 mM isoprenaline further increased its amplitude. In the presence of cGMP it alone also produced an increase of the calcium current to -0.52 nA/50pF and addition of isoprenaline or forskolin increased its magnitude to -[0.55~0.95] nA/50pF. Simultaneous application of cGMP and cAMP increased the calcium current to -0.67 nA/50pF. Among the cGMP analogues, 8-Br-cGMP was the most potent stimulant for the calcium current activation. From the above results it could be concluded tlat cGMP increases the calcium current not through cAMP dependent protein kinase nor cAMP dependent phosphodiesterase pathway, but through independent phosphorylation pathway, possibly cGMP dependent protein kinase pathway.

• Korean journal of food and cookery science
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• v.12 no.1
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• pp.6-12
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• 1996

The survival and growth of Vibrio parahaemolyticus in tryptic soy broth(TSB), flounder homogenate and oyster homogenate with 0 or 5% of ethanol was tested at -20, 5, 35, 45 and 50$^{\circ}C$. Growth pattern of V. parahaemolyticus was similar in TSB and flounder homogenate but slightly poor in oyster homogenate at 35$^{\circ}C$. Growth occured at 5% ethanol, in TSB and flounder homogenate after a prolonged lag period but decreased in oyster homogenate during incubation at 35$^{\circ}C$. TSB and fish homogenates containing 0 or 5% of ethanol were inoculated with 10$\^$6/-10$\^$7/ cells/ml of V. parahaemolyticus and cold or heat resistance of the cells were determined at -20, 5, 45 and 50$^{\circ}C$. At 5$^{\circ}C$, the viability in culture broth with 5% of ethanol or without ethanol was not vary with the culture broth. In the presence of 5% of ethanol at -20$^{\circ}C$, cells of V. parahaemolyticus in flounder homogenate and oyster homogenate were more significantly inhibited than in TSB. The D-valves for V. parahaemolyticu at 45 and 50$^{\circ}C$ was significantly lower in oyster homogenate than in TSB and flounder homogenate with 5% of ethanol or without ethanol. The D-values in each culture broth without ethanol were 1.9-3.5 times of that value in each culture broth containing 5% of ethanol at 45 and 50$^{\circ}C$.

• Journal of Sensor Science and Technology
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• v.17 no.6
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• pp.414-417
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• 2008

This paper describes the fabrication of a Pd/poly 3C-SiC Schottky diode and its characteristics, in which the poly 3C-SiC layer and Pd Schottky contact were deposited by using APCVD and sputter, respectively. Crystalline quality, uniformity, and preferred orientations of the Pd thin film were evaluated by SEM and XRD, respectively. Pd/poly 3C-SiC schottky diodes were fabricated and characterized by I-V and C-V measurements. Its electric current density Js and barrier height voltage were measured as $2{\times}10^{-3}A/cm^2$ and 0.58 eV, respectively. These devices were operated until about $400^{\circ}C$. Therefore, from these results, Pd/poly 3C-SiC Schottky devices have very high potential for high temperature chemical sensor applications.

• Biomedical Science Letters
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• v.8 no.3
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• pp.143-154
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• 2002

The effect of cardiopulmonary bypass (CPB) on cerebral physiology during heart surgery remains incompletely understood. This study was carried out to investigate changes of cerebral metabolism and the association between the changes and clinical factors during heart surgery. Seventy adult patients (n=70) scheduled for elective cardiac surgery were participated in the present study. Middle cerebral artery blood flow velocity (V$_{MCA}$), cerebral arteriovenous oxygen content difference (C(a-v)O$_2$), cerebral oxygen extraction (COE), and modified cerebral metabolic rate for oxygen (MCMRO$_2$) were measured during six phases of the operation; Pre-CPB, CPB-10 min, Rewarm-1 (nasopharyngeal temperature 34$^{\circ}C$), Rewarm-2 (nasopharyngeal temperature 37$^{\circ}C$), CPB-off, and Post-OP (at skin closure after CPB-off). Each relationship of age, arterial blood gas parameters, or other variables to V$_{MCA}2$, C(a-v)O$_2$, COE, or MCMRO$_2$ was evaluated. V$_{MCA}$ increased (P<0.0001) whereas C(a-v)O$_2$ decreased (P<0.01) throughout the five phases of the operation compared to Pre-CPB value (control). COE diminished at CPB-10, Rewarm-1, and CPB-off (P<0.05) while MCMRO$_2$ reduced at CPB-10 and Rewarm-1 (P<0.05) compared to Pre-CPB value. Positive correlation was found between age and cerebral metabolic parameters (V$_{MCA}$, C(a-v)O$_2$, COE, or MCMRO$_2$) during CPB (range r=0.24 to 0.38, p<0.05). Four cerebral metabolic parameters had partially negative or positive correlation with arterial blood gas parameters and other variables (arterial blood pH, $O_2$ tension, $O_2$ content, $CO_2$ tension, blood pressure, blood flow, temperature, or hematocrit) during the operation. In conclusion, CPB led to marked alterations of cerebral metabolism and age, pH, and $CO_2$ tension profoundly influenced the changes during cardiac surgery.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2003.05a
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• pp.53-53
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• 2003

Plasma polymerized organic thin films were deposited on Si(100) glass and metal substrates using thiophene and ethylcyclohexane precursors by PECVD method. In order to compare electrochemical properties of the as-grown thin films, the effects of the RF plasma power in the range of 30~100 W. AFM showed that the polymer films with smooth surface and sharp interface could be grown under various deposition conditions. Impedance analyzer was utilized for the determination of I-V curve for leakage current density and C-V for dielectric constants, respectively. To obtain C-V curve, we used a MIM structure of metal(Al)-insulator(plasma polymerized thin film)-metal(Pt) structure. Al as the electrode was evaporated on the thiophene films that grew on Pt coated silicon substrates, and the dielectric constants of the as-grown films were then calculated from C- V data measured at 1MHz. From the electrical property measurements such as I-V and C-V characteristics, the minimum dielectric constant and the best leakage current of thiophene thin films were obtained to be about 3.22 and $1{\;}{\times}10^{-11}{\;}A/cm^2$. However, in case of ethylcyclohexane thin films, the minimum dielectric constant and the best leakage current were obtained to be about 3.11 and $5{\;}{\times}10^{-12}{\;}A/cm^2$.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.1077-1080
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• 1998

In this paper, a simple low-power current-mode CMOS wotage reference circuit is proposed. The reference circuit of enhancement-mode MOS transistors and resistors. Temperature compensation is made by adding a current component proportional to a thermal voltage to a current component proportional to a threshold voltage. The designed circuit has been simulated using a $0.65\mu\textrm{m}$ n-well CMOS process parameters. The simulation results show that the reference circuit has a temperature coefficient less than $7.8ppm/^{\circ}C$ and a power-supply(VDD) coefficient less than 0.079%/V for a temperature range from $-30^{\circ}C$ to $130^{\circ}C$ and a VDD range from 4.0V to 12V. The power consumption is 105㎼ for VDD=5V and $T=30^{\circ}C.$ The proposed reference circuit can be designed to generate a wide range of reference voltages owing to its current-mode operation.

• Journal of the Korean Electrochemical Society
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• v.24 no.4
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• pp.113-119
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• 2021

In this study, impurity free V^3.5+ electrolytes were prepared using formic acid as a reducing agent and PtD/C as a catalyst and it was applied to VRFB. The well-oriented 3D dendrite structure of the PtD/C catalyst showed high catalytic activity in formic acid oxidation reaction and vanadium reduction reaction. As a result, the conversion ratio of electrolyte using the PtD/C was 2.73 mol g^-1 h^-1, which was higher than that of 1.67 mol g^-1 h^-1 of Pt/C prepared by the polyol method. In addition, in the VRFB charging and discharging experiment, the V^3.5+ electrolyte produced by the catalytic reaction showed the same performance as the standard V^3.5+ electrolyte prepared by the electrolytic method, thus proving that it can be used as an electrolyte for VRFB.

• Textile Coloration and Finishing
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• v.6 no.2
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• pp.30-39
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• 1994

To study the printing behaviors of Polyester and cotton(P/C) fabrics printed with disperse and reactive dyes, the effects of alkalis on the fixation of reactive dyes and the alkali-stability of disperse dyes in various methods of fixation were examined. The anthraquinone disperse dyes which have diamino derivatives as substituents without hydroxy group, such as C.I. Disperse Violet 1(D.V.1), C.I. Disperse Violet 28(D.V.28) and C.I.Disperse Blue 60(D.B.60) showed good results of fixation without regard to the concentration of NaHCO$_3$. In case of high temperature steaming(HTS) and unsaturated steaming(US)/HTS, D.V. 1 was alkali-stable and effective for P/C printing. A good result was obtained with D.V.1 and C.I.Reactive Orange 13(R.O.13) paste of 4% $K_{2}CO_{3}$. It was found that the unfixed D.V.28 bearing chloro group can hinder the fixation of monochlorotriaxinyl reactive dyes, and D.B.60 made little stain on 100% cotton. In thermosol(Tm), the dye uptake of D.V.1 was not decreased so much, but those of D.V.28 and D.B.60 were greatly decreased.

• Korean Journal of Food Science and Technology
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• v.14 no.3
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• pp.257-264
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• 1982

In the present stud changes of some chemical and physical properties of a soybean oil, aerated at 120 ml/min through a porous gas distributor and oxidized at $45^{\circ}C{\sim}180^{\circ}C$, was investigated. The results of the study were as follows: The peroxide, thiobarbituric acid, and iodine value of the soybean oil which was aerated at 120 ml/min increased rapidly as oxidation temperature exceeded over $80^{\circ}C$. The acid value of the oil increased very rapidly as the oxidation temperature passed over $160^{\circ}C$. The content of the unsaturated fatty acid of the oil decreased considerably as the oxidation temperature exceeded over $80^{\circ}C$, whereas that of the saturated fatty acid did not change appreciably. This related well to the changes of the iodine value of the oil subjected to the same experimental conditions. The viscosity and refractive index of the oil increased rapidly as the oxidation temperature passed over $180^{\circ}C$. The following linear relationship hold for the viscosity and refractive index of the oil in the present study. $$V=Aexp({\frac{E}{RT}})$$ where V=viscosity(poise), A=constant, E=activation energy for viscous flow, R=gas constant, T=oxidation temperature$(^{\circ}K)$. The following relationship also hold for the viscosity and refractive index$({n^{20}}_D)$ of the oil at the present experimental conditions. $${n^{20}}_D=1.4614+7.333{\times}10^{-5}t+2.9612{\times}10^{-3}\;InV$$ where t=temperature$(^{\circ}C)$ at which the viscosity was measured.