• Journal of the Korean institute of surface engineering
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• v.53 no.5
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• pp.265-270
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• 2020

We investigated mechanochemical radical, which is concomitant with chemical lift-off lithography(CLL), on the self-assembled monolayer(SAM)/electrodes and a polydimethylsiloxane(PDMS) using a colorimetric and a spectroscopic method. The 11-mercaptoundecanol(MUO)/Au or the 11-hydroxyundecylphosphonic acid (HUPA)/ITO were contacted with bare or activated PDMS. After contact, the each of SAM/substrates and the PDMS were immersed in a 2,2 Diphenyl-1-picrylhydrazyl(DPPH) radical scavenger. The color of the DPPH exposed to the PDMS was changed from purple to yellow and the absorbance decreased definitely at 515 nm wavelength. The SAM/substrates, however, have caused small changes in spectroscopic property, indicating no existence of radical species. We concluded that mechanochemical radicals were formed by homolytic cleavage of PDMS molecules upon external force and hardly transferred on the SAM/substrates.

• Korean Journal of Pharmacognosy
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• v.19 no.2
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• pp.93-96
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• 1988

Three flavonoids were isolated from Epimedium koreanum and identified as quercetin(1), $anhydroicaritin-3-O-{\alpha}-rhamnoside(2)$ and icariin(3) by spectroscopic methods. The former two compounds are the first isolation from this plant.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.55-56
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• 2002

Nanotribological characteristics of hydrophobic surfaces were studied experimentally using an atomic force microscope (AFM). Two kinds of thiolic self-assembled monolayers (SAM) having different spacer chains and their mixture were deposited onto gold-coated mica, where the deposited SAM resulted in the hydrophobic nature. Results showed that the mixed thiolic SAMs resulted in low adhesion and friction in nano-scale contact. It was argued that the water wetting characteristics played a central role on nano-scale adhesion and friction. Also the effect of mixing the thiolic SAMs were discussed on the basis of real area on contact and the stiffness of the SAM layers.

• Journal of National Security and Military Science
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• s.9
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• pp.1-139
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• 2011

• Polymer Science and Technology
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• v.8 no.4
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• pp.391-397
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• 1997

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.164-166
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• 2013

Using a simple random walk model, this study simulated the growth of a self-assembled monolayer (SAM) pattern generated by dip-pen nanolithography (DPN). In this model, the SAM pattern grew mainly via the serial pushing of molecules deposited from the tip. This study examined various SAM patterns, such as lines, crosses and letters, by changing the tip scan speed.

• Korean Journal of Pharmacognosy
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• v.27 no.4
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• pp.371-377
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• 1996

In previous studies we reported that the levels of RBC, hemoglobulin (HGB) and hematocrit (HCT) in SAM P6 were increased significantly from 7 day after oral administration of the pilose antler extract, 5 g/kg/day, and were lasted during the study. Thus, this study was performed to elucidate mechanism of erythropoietic action by the extract administration. SAM R1 and SAM P6 were chosen as experimental animals. At age of 12 weeks, pilose antler extract were given 0.3 and 5 g/kg/day (p.o.) each for 0, 7 and 14 days in both animals. Complete blood cells such as RBC, HGB, and HCT were counted. And plasma concentration of erythropoietin (EPO) which is the major regulator of erythropoiesis was measured using $^{125}I-antierythropoietin$ IgG. Total iron concentration in plasma was also analyzed. The levels of RBC and HCT were increased significantly after administration at both doses of 0.3 and 5 g/kg/day in SAM P6, however, these were increased only at dose of 5 g/kg/day in SAM R1. The plasma EPO concentration was increased significantly after administration in SAM P6. The plasma concentrations of total iron were significantly decreased after administration of the extract in SAM P6. These results suggest that the changes in erythropoietic effects after the administration of pilose antler extract may be mediated, at least in part, through the change in the plasma EPO.

• Journal of the Korean Electrochemical Society
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• v.5 no.3
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• pp.143-152
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• 2002

The growth of Polypyrrole film has been investigated during electropolymerization in an aqueous solution on bare and SAM modified gold electrodes by in-situ EQCM and ex-situ AFM. According to the result of cyclic voltammetry measurements, in the case of a bare gold electrode, the electrochemical deposition of polypyrrole were dependent on the limiting oxidative potential, but not on scan numbers. When the limiting potential higher than 0.8 V was applied on the electrode, the amount of polypyrrole deposited on a gold electrode was rapidly increased and the abnormal mass change attributed to the rearrangement of polypyrrole films was observed as the scan number increased. The polypyrrole film Prepared on electrodes modified with 1-dodecanethiol SAM or thiophene SAM grew 3-dimensionally with the rearrangement of film. However, in the case of BPUS SAM, 2-dimensional layer-by-layer growth of film was observed without the rearrangement of film. AFM images showed films with chain-shaped and/ or donut-shaped polymers when grown rapidly and a wrinkled film at the steady state condition.

• The Journal of Korea Robotics Society
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• v.16 no.3
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• pp.179-188
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• 2021

Construction monitoring is one of the key modules in smart construction. Unlike structured urban environment, construction site mapping is challenging due to the characteristics of an unstructured environment. For example, irregular feature points and matching prohibit creating a map for management. To tackle this issue, we propose a system for data acquisition in unstructured environment and a framework for Intensity and Ambient Enhanced Lidar Inertial Odometry via Smoothing and Mapping, IA-LIO-SAM, that achieves highly accurate robot trajectories and mapping. IA-LIO-SAM utilizes a factor graph same as Tightly-coupled Lidar Inertial Odometry via Smoothing and Mapping (LIO-SAM). Enhancing the existing LIO-SAM, IA-LIO-SAM leverages point's intensity and ambient value to remove unnecessary feature points. These additional values also perform as a new factor of the K-Nearest Neighbor algorithm (KNN), allowing accurate comparisons between stored points and scanned points. The performance was verified in three different environments and compared with LIO-SAM.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.444-451
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• 1999

We performed this study to determine the radioprotective effect of Sam Ryung Baek Chul San (San Ling Bai Shu San), as a prescription of traditional Oriental medicine, and its major ingredients. Jejunal crypt survival, endogenous spleen colony formation, and apoptosis in jejunal crypt cells were investigated in irradiated mice with high and low dose of rays. Sam Ryung Baek Chul San administration before irradiation increased the formation of endogenous spleen colony(p<0.05) and reduced the frequency of radiation induced apoptosis(p<0.05). In the experiment on the effect of ingredients of Sam Ryung Baek Chul San, the result indicated that the extracts of Panax ginseng, Poria cocos and Coix lacryma jabi might have the major radioprotective effects. Although the mechanisms of these inhibitory effects remain to be elucidated, these results indicated that Sam Ryung Baek Chul San might be a useful radioprotector, especially since it is a relatively nontoxic natural product.