• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.08a
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• pp.107-109
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• 2003

The magnetostriction of FeCoGe/phenol composites is measured under the external magnetic field. A few Measurement are carried out by using the electrical-resistance strain gage, the Wheaton Bridge for eliminating the unnecessary voltage, the lock-in-amplifier for the signal amplification and noise filtering. When the external magnetic field is applied to the longitudinal direction against those samples which is the 10wt.% phenol in composites, the theoretical maximum strain of 120ppm is obtained. According to the larger strain than that of others solid state actuators and piezoelectric actuators. FeCoGe/phenol composites could be useful as an actuator.

• Journal of Korean Vacuum Science & Technology
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• v.4 no.1
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• pp.11-17
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• 2000

The low temperature electron mobilities were investigated in Si/$Si_{1-x}Ge_{x}$ modulation Doped (MOD) quantum well structure with thermally grown oxide. N-type Si/$Si_{1-x}Ge_{x}$ structures were fabricated by a gas source MBE. Thermal oxidation was carried out in a dry $O_2$ atmosphere at $700^{\circ}C$ for 7 hours. Electron mobilities were measured by a Hall effect and a magnetoresistant effect at low temperatures down to 0.4 K. Pronounced Shubnikov-de Haas (SdH) oscillations were observed at a low temperature showing two dimensional electron gases (2 DEG) in a tensile strained Si quantum well. The electron sheet density ($n_{s}$) of 1.5${\times}$$10^{12}$[$cm^{-2}$] and corresponding electron mobility of 14200 [$cm^2$$V^{-1}$$s^{-1}$] were obtained at low temperature of 0.4 K from Si/$Si_{1-x}Ge_{x}$ MOD quantum well structure with thermally grown oxide.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.9
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• pp.765-770
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• 2003

We have developed a low-temperature, and low-pressure radical induced oxidation (RIO) technology, so that high-quality ultrathin silicon dioxide layers have been effectively produced with a high reproducibility, and successfully employed to realize high performace SiGe heterostructure complementary MOSFETs (HCMOS) lot the first time. The obtained oxide layer showed comparable leakage and breakdown properties to conventional furnace gate oxides, and no hysteresis was observed during high-frequency capacitance-voltage characterization. Strained SiGe HCMOS transistors with a 2.5 nm-thick gate oxide layer grown by this method exhibited excellent device properties. These suggest that the present technique is particularly suitable for HCMOS devices requiring a fast and high-precision gate oxidation process with a low thermal budget.

• Advances in aircraft and spacecraft science
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• v.2 no.3
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• pp.233-248
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• 2015

Frame structures have been traditionally represented as an assembling of components, these last described within the beam theory framework. In the case of frames involving complex components in which classical beam theory could fail, 3D descriptions seem the only valid route for performing accurate enough analyses. In this work we propose a framework for frame structure analyses that proceeds by assembling the condensed parametric rigidity matrices associated with the elementary beams composing the beams involved in the frame structure. This approach allows a macroscopic analysis in which only the condensed degrees of freedom at the elementary beams interfaces are considered, while fine 3D parametric descriptions are retained for local analyses.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.325-328
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• 2003

The magnetostriction of FeCoGeW/phenol composites is measured under the external magnetic field. A few Measurement are carried out by using the electrical-resistance strain gage, the Wheaton Bridge for eliminating the unnecessary voltage, the lock-in-amplifier for the signal amplification and noise filtering. When the external magnetic field is applied to the longitudinal direction against those samples which is the 10wt.% phenol in composites, the theoretical maximum strain of 120ppm is obtained. According to the larger strain than that of others solid state actuators and piezoelectric actuators. FeCoGeW/phenol composites could be useful as an actuator.

• YAKHAK HOEJI
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• v.27 no.1
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• pp.1-10
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• 1983

Voltammetric deposition and differential pulse anodic stripping (DPASV) of Ge(IV)at a gold electrode was investigated. Germanium (IV) exhibits two stripping peaks by DPASV in sodium borate solution, the first peak at about -1.1v. vs SCE and the second one, in the range of -0.6 to -0.2v. vs SCE. Factors affecting the sensitivity and precision included the nature of working electrode, supporting electrolytes, deposition potential, deposition time, pH, pulse height, voltage scan rate. The relative standard deviation of the measurements of the peak currents, for 100ng/ml Ge(IV), was less than ${\pm}3%$. The detection limit of Ge(IV) was 0.01ng/ml. Percent recovery in the extraction procedure of Ge(IV) from matrices by benzene in c-HCl, followed by back extraction with saturated borax solution, ranged from 96 to 104%.

• Korean Journal of Environmental Agriculture
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• v.27 no.3
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• pp.245-252
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• 2008

The growth characteristics and the Germanium (Ge) uptake of rice plant (Hopyungbyeo) in soil with Ge were investigated under different soil textures to obtain the basic information for agricultural utilization of Ge. This study was carried out in the Wagner pot ($15,000^{-1}a$). Ge concentration in soils such as clay loam, silt loam, loam and sandy loam for rice plant cultivation was treated at $8mg\;kg^{-1}$. The growth status of rice plant was almost similar in all soil texture, and rice yield was higher in the order of silt loam > clay loam > loam > sandy loam. In rice bran, the Ge uptakes in silt loam, clay loam, loam and sandy loam were 980, 868, 754 and $803{\mu}g\;pot^{-1}$, respectively. The Ge uptakes of brown rice and polish rice were greater in the order of silt loam > sandy loam > clay loam > loam. In silt loam, the Ge uptake rates in leaf, stem, root, rice bran and brown rice were 19.7, 2.3, 0.03, 3.1 and 0.44%, respectively. Therefore, under the given experimental condition the optimum soil texture for production of functional rice with Ge is a silt loam.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.5
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• pp.285-290
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• 2015

The phase change memory material is an active element in phase change memory and exhibits reversible phase transition behavior by thermal energy input. The doping of the phase change memory material with Ga leads to the increase of its crystallization temperature and the improvement of its amorphous stability. In this study, we investigated the effect of GaGe sputtering power on the formation of the phase change memory material including Ga. The deposition rate linearly increased to a maximum of 127 nm and the surface roughness remained uniform as the GaGe sputtering power increased in the range from 0 to 75 W. The Ga concentration in the thin film material abruptly increased at the critical sputtering power of 60 W. This influence of GaGe sputtering power was confirmed to result from a combined sputtering-evaporation process of Ga occurring due to the low melting point of Ga ($29.77^{\circ}C$).

• YAKHAK HOEJI
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• v.42 no.3
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• pp.330-335
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• 1998

Gastrodia elata (GE) is a oriental medicinal herb which has been used traditionally for the treatment of various brain diseases including convulsion and epilepsy. In orde r to examine the mechanism of anticonvulsive effect, we treated the methanol extract of GE (500mg/kg, P.0) to the pentylenetetrazole (PTZ)-induced convulsive rats. Methanol extracts of GE significantly inhibited (35%) the convulsion state as well as the level of lipid peroxidation (25%) in the brain. The ether fraction of methanol extracts among the others effectively ibhibited in vitro lipid peroxidation dose dependently ($5.O{\times}10^{-6}{\sim}2.O{\times}1O^{-5}g/ml$). The scavenging effect on hydroxy radicals was found in all the fractions of ether, butanol, and dichloromethane. These results suggest that the anticonvulsive effect of GE is possibly due to the antioxidative effects of the active components in GE.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.5
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• pp.329-333
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• 2012

For phase transition method, good record sensitivity, low heat radiation, fast crystallization and hi-resolution are essential. Also, a retention time is very important part for phase-transition. In our past papers, we chose composition of $Ge_1Se_1Te_2$ material to use a Se factor which has good optical sensitivity than conventional Sb. Sb/Ge-Se-Te thin films are fabricated and irradiated with UV light source to investigate a reversible phase change by Sb-doped condition. Because of Sb atoms, the Sb inserted sample showed better performance than conventional one. We should note that this novel one showed another possibility for phase-change random access memory.