• Proceedings of the Ginseng society Conference
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• 1998.06a
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• pp.31-39
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• 1998

We have investigated the antinociceptive efficacy of ginseng saponins in mice using l% formalin, which induce two phases of pain (acute and tonic pains) and is known to induce a clinically related pain. Ginseng total saponins (GTS) relieved both phases of pain with EDso of 162 mghg for acute and 92 mg/kg for tonic pain, respectively. Both protopanaxadiol (PD) and protopanaxatriol (PT) saponins did not attenuated acute phase of pain but relieved tonic phase of pain with EDso of 45 mg/kg for PD saponins and 105 mghg for PT saponins, respectively. Moreover, ginsenoside Rc, Rd, and Re among representative ginsenosides such as Rbl, Rc, Rd, Re and Rgl relieved slightly but significantly acute phase of pain and strongly attenuated tonic phase of pain but Rf relieved only tonic phase of pain. However, PD and PT saponins, and the individual ginsenosides tested except GTS did not greatly attenuate thermal noxious pain (tail-flick test). These results suggest that single ginsenoside or mixture of various ginsenosides mainly induce differential antinociception in mice.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.631-635
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• 2000

Recently, the epoxy molded type PT for indoor and applied 25.8kV was often distroyed by degradation of insulation that effected many electric stress and defect of manufactured goods. therefore In this work, We can present a method of solution in the process of produce the PT through analysis of experiments. In order to reduce the PD (Partial Discharge) which was occurred at the insulation material of epoxy resin, we has many tried to remove faults In the process of the products,

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.133-133
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• 2013

For both oxygen reduction (ORR) and hydrogen oxidation reactions (HOR) of proton electrolyte membrane fuel cells (PEMFCs), alloying Pt with another transition metal usually results in a higher activity relative to pure Pt, mainly due to electronic modification of Pt and bifunctional behaviour of alloy surface for ORR and HOR, respectively. However, activity and stability are closely related to the preparation of alloy nanoparticles. Preparation conditions of alloy nanoparticles have strong influence on surface composition, oxidation state, nanoparticle size, shape, and contamination, which result from a large difference in redox priority of metal precursors, intrinsic properties of metals, increasedreactivity of nanocrystallites, and interactions with constituents for the synthesis such as solvent, stabilizer, and reducing agent, etc. Carbon-supported Pt-Ni alloy nanoparticles were prepared by the borohydride reduction method in anhydrous solvent. Pt-Ru alloy nanoparticles supported on carbon black were also prepared by the similar synthetic method to that of Pt-Ni. Since electrocatalytic reactions are strongly dependent on the surface structure of metal catalysts, the atom-leveled design of the surface structure plays a significant role in a high catalytic activity and the utilization of electrocatalysts. Therefore, surface-modified electrocatalysts have attracted much attention due to their unique structure and new electronic and electrocatalytic properties. The carbon-supported Au and Pd nanoparticles were adapted as the substrate and the successive reduction process was used for depositing Pt and PtM (M=Ru, Pd, and Rh) bimetallic elements on the surface of Au and Pd nanoparticles. Distinct features of the overlayers for electrocatalytic activities including methanol oxidation, formic acid oxidation, and oxygen reduction were investigated.

• Journal of Environmental Impact Assessment
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• v.27 no.5
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• pp.405-416
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• 2018

In this research, the distribution of Platinum Group Elements (PGEs) at roadside dust in Daejeon, Korea was examined using an ICP-MS (Inductively Coupled Plasma-Mass Spectrometry) technique. For the quality assurance of the determination, method validation based on its accuracy and precision was conducted using SRM (Standard Reference Material). It was found that the relative errors of Pt, Pd, and Rh against each SRM value were -0.7%, -10.0%, and -20.4%, respectively, while relative standard deviations for three elements were less than 10%. The concentrations of Pt, Pd and Rh in roadside dust averaged as $17.4{\pm}9.2{\mu}g/kg$, $283.6{\pm}20.5{\mu}g/kg$, and $7.3{\pm}2.8{\mu}g/kg$, respectively. The concentrations of Pt and Rh have significantly higher distribution patterns in the dust at roadside and underground parking lot than those in soil of the background or other urban area. The correlation analysis between concentrations of PGEs in roadside dust indicates that the distribution of Pt and Rh concentration were strongly affected by automobile sources.

• Journal of the Korean Chemical Society
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• v.27 no.4
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• pp.268-272
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• 1983

Polyurethane foam impregnated with ${\beta}$-diphenylglyoxime has been applied to the extraction of palladium(II) from platinum(IV) and nickel(II) in aqueous solution. Palladium(II) is quantitatively extracted from $0.01{sim}0.05M$ HCl. On the other hand, platinum(Ⅳ) was slightly extracted and nickel(II) was not found to be extraction in the same experimental condition. Based on the results obtained, the selective separation, removal and recovery of Pd(II) from Pt(IV) or Ni(II) was possible by batch or elution method.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.2
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• pp.121-130
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• 1996

The catalysts composed of Pt, Pd and W as active-components, $Al_{2}O_{3}$ and $SiO_{2}$ as supports, were perpared on the honeycomb type substrate and characterized by BET, SEM, TGA, FT-IR and XRD for diesel emission control. CO, $C_{3}H_{6}$, and $SO_{2}$ oxidation was carried out over these catalysts in a fixed bed continuous flow reactor at the temperatures between 100-500.deg.C and reactant gas was composed of 10 vol.% $O_{2}$, 1 vol.% CO, 0.8 vol.% $C_{3}H_{6}$ and 88.2 vol.% $N_{2}$. It was found that under these experimental conditions, the CO, $C_{3}H_{6}$ oxidation activity of Pt-W catalyst was higher than that of any other prepared catalyst, and this catalyst had also a good inhibition effect on $SO_{2}$ oxidation. Also it was show that the influence of $SO_{2}$ on $Al_{2}O_{3}$ was more sever than that of $SO_{2}$ on $SiO_{2}$.

• Korean Chemical Engineering Research
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• v.44 no.3
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• pp.314-318
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• 2006

Direct formic acid fuel cells (DFAFCs) are potential alternative power sources for portable devices such as cellular phone, personal digital assistants (PDA) and laptop computers. In this study, we developed the catalysts for great performance of fuel cell, and investigated their characteristics by using EDS and SEM. Pt-Pd catalysts showed uniform size and homogeneous distribution. As the content of palladium increased, the performance of DFAFC increased. Pd black showed the greatest performance among the five catalysts tested. Also, Pt-Pd (1:1) catalyst had an excellent maximum power density of $120mW/cm^2$. As the operating temperature increased, fuel cell performance was increased due to a reaction activity increases of catalyst. But, temperature had only a slight effect on the performance of fuel cell in the best activity range of membrane.

• Journal of the Korean Chemical Society
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• v.30 no.3
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• pp.320-326
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• 1986

The antitumor properities of metal are not limited to Pt(II) complexes. Recently, it was reported that some Pt(II) and Pd(II) complexes with sulfur and nitrogen ligands had potential antitumor reactivity. Pt(II) complexes is toxic drug for anticancer. Therefore, the complexes of Pd(II) with adenine, uracil, cytosine and malonate ligands are interesting for anticancer drug. We synthesized new palladium complexes containing nucleosides. The reactions of Pd(II) with adenine, uracil, cytosine and malonate ligands have been studied in aqueous solutions. The complexes isolated from these reactions have the following formulas; $[Pd(en)(C_5H_5N_5)_2](NO_3)_2,\;[Pd(en)(C_4H_3N_2O_2)Cl],\;[Pd(en)(C_3H_2O_4)]\;and\;[Pd(en)(C_4H_5N_3O)_2](NO_3)_2{\cdot}(C_4H_5N_3O)$. The compounds have been identified by elemental analysis, mass spectra, infrared spectra and electronic spectra.

• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.442-445
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• 1999

In this work, to detect of hydrogen in DI water in the generator area of nuclear power plants was fabricated Pd/Pt gate MISFET sensor using Pd membrane. $H_2$ permeation through Pd accounts for external mass transfer, surface adsorption and desorption, transitions to and from the bulk metal, and diffusion within the metal. The identification of pinholes in the generator area of plant is an important safety consideration, as hydrogen build-up gives rise to explosion. For this type of application the sensor needs to be isolated in DI water, accordingly, a Pd membrane was used to separate the DI water. The hydrogen in the DI water was then absorbed on the Pd thin film and diffused into the oil through the thin film. The Pd/Pt gate MISFET sensor, encapsulated by oil, will thereby detect permeated hydrogen.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.11a
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• pp.623-623
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• 2008