• Journal of Electrical Engineering and Technology
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• v.13 no.4
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• pp.1638-1643
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• 2018

Multi-layer ceramic capacitors as decoupling capacitor were fabricated by dielectric composition with a high dielectric constant. The fabricated decoupling capacitors were embedded in the PCB of the 10G RF transceiver module and evaluated for the characteristics of electrical noise by the level of AC input voltage. In order to further improve the electrical properties of the $BaTiO_3$ based composite, glass frit, MgO, $Y_2O_3$, $Mn_3O$, $V_2O_5$, $BaCO_3$, $SiO_2$, and $Al_2O_3$ were used as additives. The electrical properties of the composites were determined by various amounts of additives and optimum sintering temperature. As a result of the optimized composite, it was possible to obtain a density of $5.77g/cm^3$, a dielectric constant of 1994, and an insulation resistance of $2.91{\times}10^{12}{\Omega}$ at an additive content of 5wt% and a sintering temperature of $1250^{\circ}C$. After forming a $2.5{\mu}m$ green sheet using the doctor blade method, a total of 77 layers were laminated and sintered at $1180^{\circ}C$. A decoupling capacitor with a size of $0.6mm(W){\times}0.3mm(L){\times}0.3mm(T)$ (width, length and thickness, respectively) and a capacitance of 100 nF was embedded using a PCB process for the 10G RF Transceiver modules. In the range of AC input voltage 400mmV @ 500kHz to 2200mV @ 900kHz, the embedded 10G RF Transceiver modules evaluated that it has better electrical performance than the non-embedded modules.

• Journal of Life Science
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• v.28 no.6
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• pp.671-680
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• 2018

Hypoglycemic and hypolipidemic effects of Jerusalem artichoke composites (JAP) with extracts of G. procumbens (12.5%), M. charantia (12.5%), and C. longa (12.5%) to H. tuberosus concentrate (JA, 50%) were evaluated in streptozotocin (STZ) induced diabetic rats. Rats were divided into seven groups: normal (Normal), diabetic control (Diabetic), group fed G. procumbens extract (0.5 g/kg bw, D-GPE), group fed JAP (0.5 g/kg bw, D-JAP1; 1.5 g/kg bw, D-JAP2), group fed JA (0.5 g/kg bw, D-JA), and group fed Metformin (0.2 g/kg bw, D-MET) as a positive control. The blood glucose levels over 4 weeks were significantly decreased in the D-JAP2 and D-MET groups compared to the other groups after 3 weeks. The serum insulin level was not significant among the groups fed an experimental diet, but the HOMA-IR value was significantly decreased compared to the diabetic control group. AST and ALT activities in the serum were lowest in D-JAP1. Total lipid and triglyceride contents in the serum decreased in the groups fed an experimental diet, and the HDL-C contents of D-GPE, D-JAP1, and D-JAP2 were significantly increased compared to the diabetic control group. Triglyceride contents in the liver tissue were significantly lower in the D-GPE, D-JAP1, and D-JAP2 groups, and hepatic TBARS content was significantly decreased in the D-JAP1 and D-JAP2 groups compared to the diabetic control group. Hepatic antioxidative enzyme levels, such as SOD, catalase, and GSH-Px, were significantly elevated in groups fed an experimental diet compared to the diabetic control group. Therefore, JAP may be more effective than JA in the human body due to its hypoglycemic and hypolipidemic activities.

• Elastomers and Composites
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• v.45 no.2
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• pp.112-121
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• 2010

In this study, styrene butadiene rubber(SBR)/organoclay nanocomposites were manufactured using the latex method with 3-aminopropyltriethoxysilane(APTES) as a modifier. The X-ray diffraction(XRD), transmission electron microscopy(TEM) images, Fourier transform infrared(FTIR) spectroscopy, swelling ratio and mechanical properties were measured in order to study the interaction between filler and rubber according to the mixing temperature in the internal mixer. In the case of SBR/APTES-MMT compounds, the dispersion of the silicates within the rubber matrix was enhanced, and thereby, the mechanical properties were improved. The characteristic bands of Si-O-C in APTES disappeared after hydrolysis reaction in the MMT-suspension solution and the peak of hydroxyl group was increased. Therefore the formation of chemical bonds between the hydroxyl group generated from APTES on the silicate surface and the ethoxy group of bis(triethoxysilylpropyl) tetrasulfide(TESPT) was possible. Consequently, the 300% modulus of SBR/APTES-MMT compounds was further improved in the case of using TESPT as a coupling agent. However, the silanization reaction between APTES and TESPT was not affected significantly according to the increase of mixing temperature in the internal mixer.