• 한국재료학회지
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• 제19권10호
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• pp.527-532
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• 2009

The electrochromic properties of Au nanoparticles (NPs) incorporating poly (3, 4-ethylenedioxythiphene) (PEDOT) film were investigated. Trisodium citrate was used for stabilizing Au NPs to control the size. The capping molecules of the Au nanoparticles were exchanged from citrate to 2-mercaptoethanol (2-ME). Water was removed by centrifuge and Au NPs were redispersed in methanol (MeOH). Finally, we obtained ca. 11.7 nm diameter of Au NPs. The effects of 0.15 at% of Au NPs incorporation on the optical, electrical, and eletrochromic properties of PEDOT films were investigated. The electrical property and switching speed of Au/PEDOT film was slightly improved over that of PEDOT film because Au NPs play a hopping site role and affect packing density of the PEDOT chain. Through the ultra violet-visible spectra of PEDOT and Au/PEDOT films at -0.7 V (vs Ag/AgCl), blue shift of maximum absorption peak was observed from PEDOT (585.4 nm) to Au/PEDOT (572.2 nm) due to a shortening of conjugated length of PEDOT. The Au NPs interfered with the degree of conjugation and the maximum absorption peak was shifted to shorter wavelength.

• Computers and Concrete
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• 제26권3호
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• pp.275-283
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• 2020

Reinforced concrete (RC) does not provide sufficient resistance against impacts and blast loads, and the brittle structure of RC fails to protect against fractures due to the lack of shock absorption. Investigations on improving its resistance against explosion and impact have been actively conducted on high-performance fiber-reinforced cementitious composites (HPFRCCs), such as fiber-reinforced concrete and ultra-high-performance concrete. For these HPFRCCs, however, tensile strength and toughness are still significantly lower compared to compressive strength due to their limited fiber volume fraction. Therefore, in this study, the tensile behavior of slurry-infiltrated fiber-reinforced cementitious composites (SIFRCCs), which can accommodate a large number of steel fibers, was analyzed under static and dynamic loading to improve the shortcomings of RC and to enhance its explosion and impact resistance. The fiber volume fractions of SIFRCCs were set to 4%, 5%, and 6%, and three strain rate levels (maximum strain rate: 250 s^-1) were applied. As a result, the tensile strength exceeded 15 MPa under static load, and the dynamic tensile strength reached a maximum of 40 MPa. In addition, tensile characteristics, such as tensile strength, deformation capacity, and energy absorption capacity, were improved as the fiber volume fraction and strain rate increased.

• 약학회지
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• 제13권1호
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• pp.1-15
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• 1969

A new method of qualitative and quantitative determination of barbiturates in the pharmaceuticals by means of $\alpha$-picoline-copper (II) was studied. Barbiturates in the pharmaceuticals were dissolved in the mixed solvent of 33% $\alpha$-picoline-Carbontetrachloride to yield Complex Compounds of barbiturates-copper (II)-$\alpha$-picoline. Complex Compounds of barbiturates show uniformly maximum absorption at the wavelength of 540m.mu. and wre to be identified at the concentration of 1 X 10$^{-4}$ Mole, and also was to be quantitatively determined at the concentration of 1 X 10$^{-3}$ Mole. By this method barbiturates in the pharmaceuticals could be determined in the presence of various compounds such as sulpyrine, isopropylantipyrine, antipyrine, phenacetin and etc. But Barbiturates could be also determined by this method after seperation with aminopyrine, acetaminophen, acetylsalicylic acid and etc. by column chromatography. And barbiturates and acetylsalicylic acid could be also determined by simultaneous equation while their complex compounds show uniformly each maximum absorption at the Wavelength of 540 m${\mu}$ and 620 m${\mu}$. I.R. spectra of these complex compounds show identification of Barbiturates derivatives. The composition ratio of these complex compounds were : barbiturates : Cu : ${\alpha}$-picoline=2:1:2.

• 한국의류산업학회지
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• 제8권2호
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• pp.233-238
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• 2006

This research confirmed the chemical structure of Curcumine and Carthamin pigments whose pigments were separated and refined from the Curcuma longa and Carthamus Tinctorious which were natural dye using FT-IR, HPLC and so on. The cotton and the silk fabrics were dyed using a main pigment and then this research obtained the conclusion as it follows. The curcumine, the main pigment of Curcuma longa extracted from the mixed solvent of acetic anhydride and methanol ($CH_3OH$), had the maximum absorption wavelength at 504.0 nm and was confirmed as yellow natural pigment. The Carthamin, the main pigment of Carthamus Tinctorious extracted from the mixed solvent of dichloromethane and methanol, had the maximum absorption wavelength at 420.0nm. This pigment was confirmed as yellow natural pigment. The dyeing property of the main pigment about the silk fabrics was superior to that about the cotton in both the Curcuma longa and Carthamus Tinctorious, and the dyeing property of Carthamus Tinctorious was superior to that of Curcuma longa.

• 한국의상디자인학회지
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• 제17권2호
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• pp.45-61
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• 2015

In order to analysis on color difference of natural dyes, I have dyed Hanji, cotton, silk fabric and exposed them to carbon arc light. The results of experiment have been analysed by wavelength of maximum absorption, amounts of dye uptake, color difference, Hunter's value and Munsell's value. Gardenia Jasminoides is monogenetic dye, but it gained darker color by pre-mordanting method used Al mordant agent and greenish yellow color by Fe mordant agent. whereas Curcuma, an Amur cork, and bud of pagoda tree are shown as greenish yellow color, and A barberry root, Betel nut, and Rhubarb are shown as reddish yellow color. these gained khaki colored dyed fabric by Fe mordanting. In addition, Sappan wood showed great result in pre-mordanting. Especially, it gained dark red color by Al pre-mordanting. The pink color was shown by post-mordanting. and Logwood showed great dyeing result in Hanji and cotton better than silk. Specially pre-mordanting was effective. Hanji and cotton showed greenish blue color by Al pre-mordanting, and silk showed brown color.

• 패션비즈니스
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• 제14권4호
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• pp.174-184
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• 2010

This research was carried out to find the dyeing properties of Scutellaria baicalensis Georgi on the rayon and cotton fabrics. The best proper dyeing conditions were examined by changing dye concentrations, dyeing temperature, dyeing time, and dyeing repitition. Also dyeability and surface color changes were evaluated by various mordanting methods and agents. The maximum absorption of Scutellaria baicalensis Georgi were at 275nm and 362nm. The optimum dyeing conditions on the cotton were 80%, $80^{\circ}C$, 40minutes, 4 repitition, and those on the rayon were 80%, $80^{\circ}C$, 60minutes, 5 repitition. The K/S values of rayon and cotton fabrics were higher in pre-mordant than post-mordant. The K/S values on the rayons were lower than no mordant fabric except pre-Fe mordant, these on the cotton fabrics were higher than no mordant fabric except post-Al mordant. The value of ${\Delta}E$ was the highest in Fe mordanted fabrics, and higher on the cotton fabric than rayon. The surface colors of all mordanted fabrics were yellow.

• Archives of Pharmacal Research
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• 제4권2호
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• pp.75-84
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• 1981

As the cetyltrimenthy ammonium bromide (CTAB) concentration increases to $2{\times}10^{-4}$/M the absorption maximum of ethyl orange (EO) makes a blue shift from 475 mm to 395 mm. At higher concentration of CTAB than $2{\times}10^{-4}$ / M the absorption maximum shifts to higher wavelength than 395 nm. A new peak at 395 nm is shown to result from the mixed micelle due to dye stacking interaction rather than from a change in dye geometry. Because Raman spectra of EO on interaction with varying amount of CTAB are similar to that of EO in water. EO retains trans azo type on interaction with CTAB. There is a change of c.m.c.s. of CTAB for the mixed micelle in the presence of salt. The effect of added salt on C. M. C. of CTAB for the mixed micelle is given that the logarithm of the c. m. c. is a linear function of the logarithm of the sum of the c. m. c. and the concentration of added salt.

• 한국전기전자재료학회논문지
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• 제29권1호
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• pp.35-39
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• 2016

In this research, we focused on the improvement of cy3 dye's characteristics for LCD color filter. Solubility and thermal stability are main characteristics of dyes for LCD color filter. We performed experiment to change counter cation of cy3 dyes with alkoxy substituent for these purposes. These cy3 dyes (1b~5b) were prepared through the synthetic procedure of three steps. The synthesized new cy3 dyes were charaterized by using NMR, FT-IR, UV/Vis spectroscopy, and TGA. These cy3 dyes showed purple color and maximum absorption wavelength (${\lambda}_{max}$) in the range of 578~590 nm in UV/Vis spectrum. We confirmed that solubility and thermal stability of cy3 dyes were dependent on the structure of counter cation. Cy3 dyes with alkoxy substituent have good solubility in organic solvents such as dichloromethane, methanol, and acetone. Especially, Cy3 dye with 4-nitrobenzyl counter cation (5b) gave excellent solubility characteristics.

• Journal of Ginseng Research
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• 제37권4호
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• pp.451-456
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• 2013

Compound K is a major metabolite of ginsenoside Rb1, which has various pharmacological activities in vivo and in vitro. However, previous studies have focused on the pharmacokinetics of a single metabolite or the parent compound and have not described the pharmacokinetics of both compounds in humans. To investigate the pharmacokinetics of ginsenoside Rb1 and compound K, we performed an open-label, single-oral dose pharmacokinetic study using Korean Red Ginseng extract. We enrolled 10 healthy Korean male volunteers in this study. Serial blood samples were collected during 36 h after Korean Red Ginseng extract administration to determine plasma concentrations of ginsenoside Rb1 and compound K. The mean maximum plasma concentration of compound K was $8.35{\pm}3.19$ ng/mL, which was significantly higher than that of ginsenoside Rb1 ($3.94{\pm}1.97$ ng/mL). The half-life of compound K was 7 times shorter than that of ginsenoside Rb1. These results suggest that the pharmacokinetics, especially absorption, of compound K are not influenced by the pharmacokinetics of its parent compound, except the time to reach the maximum plasma concentration The delayed absorption of compound K support the evidence that the intestinal microflora play an important role in the transformation of ginsenoside Rb1 to compound K.

• 한국가스학회지
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• 제17권6호
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• pp.52-57
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• 2013

본 연구에서는 안전모 쉘 구조물의 정상부에 돌출부를 설치한 경우와 설치하지 않은 경우에 대해, 안전모의 두께와 하중면적을 변수로 변형률 에너지 밀도, 응력, 변위거동을 유한요소법으로 해석하였다. 변형률 에너지 밀도는 안전모로 전달되는 충격에너지 전달을 흡수하는 성능을 나타내는 변수로 안전모의 안전성을 고찰하는 중요한 요소 중의 하나이다. 유한요소 해석 결과에 의하면, 4,540N의 충격력이 안전모의 정상부 표면에 가해질 때 충격하중을 받는 하중면적이 증가할수록 최대응력은 선형적으로 줄어든다. 그러나, 최대 변형률 에너지 밀도는 하중면적이 증가할수록 커지는 것으로 나타났다. 변형률 에너지 밀도가 줄어들면, 안전모 착용자의 머리와 목 부분으로 전달되는 충격력은 줄어드는 것으로 나타났으며, 이것은 안전모의 충격에너지 흡수 안전성을 약화시키는 요인이 될 수 있다. 따라서, 안전모의 안전한 설계를 위해서는 정상부에 돌출 구조물을 설치하는 것이 좋지만, 이러한 수정 안전모는 충격에너지 흡수성능 측면에서는 불리함을 알 수 있다.