• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.221-224
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• 2002

Nucleophilic addition reactions of benzylamines (BA; $XC_6H_4CH_2NH_2$) to ethyl-${\alpha}$-cyanocinnamates (ECC;$YC_6H_4CH$=C(CN)COOEt) have been investigated in acetonitrile at $30.0^{\circ}C$. The rate is first order with respect to BA and ECC. The rate is slower than that expected from the additive effect of ${\sigma}^-$ or $R^-$ for the activating groups (CN and COOEt). Natural. bond orbital ${\pi}^{\ast}_{c=c}$ calculations show that the contribution of COOEt group may not be fully effective despite the coplanar molecular structure. The selectivity parameters including the cross-interaction constant (${\rho}_{xy}$ = -0.22) indicate that the addition occurs in a single step. The kinetic isotope effects ($k_H/k_D$=2.5-2.8) involving deuterated BA ($XC_6H_4CH_2ND_2$) nucleophiles and activation parameters (${\Delta}H^{\neq}=4{\sim}6\;kcal\;mol^{-1};{\Delta}S^{\neq}=-45{\sim}-52\;e.u.$) suggest a cyclic transition state in which N-$C_{\alpha}$ and H-$C_{\beta}$ bonds are formed concurrently.

• Proceedings of the Ginseng society Conference
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• 1993.09a
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• pp.206-214
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• 1993

Ginseng saponins have been known as main active principles and analyzed as the index components in ginseng and its products for quality control. But it is generally difficult to analyze the saponins in crude drug preparations. Saponins, Prosapogenins and sapogenins of crude drug preparation were identified by TLC and determined quantitatively by HPLC. $Prosapogemins-Rg_3\;-Rg_2\;and\;{\Delta}^{20}-prosapogenin$ were extracted with ethyl acetate from $50\%$ acetic acid hydrolyzates of saponin fractions and identified by TLC with lower phase of $CHCl_3/MeOH/H_2$ O\65:35:10. v/v)on silica gel plate, and quantified by HPLC on $Lichrosorb-NH_2$ column with $CH_3CN/H_2O(90:10,\;v/v).$ Sapogenins. panaxadiol and panaxatriol. were extracted with ethyl ether from $7\%-sulfuric$ acid hydrolyzates of saponin fractions and identified by TLC with chloroform/acetone(1 : 1 v/v) on silica gel plate. and quantified by HPLC on u - Bondapak $C^{18}$ column with $CH_3CN/MeOH/CHCl_3(83:10:7.\;v/v).$ These analyses of prosapogenins and sapogenins are more useful for quality control than those of saponins in crude drug preparations such as So - Shi - Ho - Tang(소시호탕), Sa - Kun - Ja - Tang(사군자탕), Yook - Kun - Ja - Tang(육군자탕), and In - Sam -Tang(인삼탕)

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1774-1777
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• 1996

In this paper, applicability of SI-PD(switching impulse - partial discharge) testing method was put on an attempt as a newly proposed diagnostic method for the underground distribution power cable system in Korea. For this purpose, SI-PD testing equipment was designed, and tests were performed using artificial needle-type defects integrated into the 22.9 kV CN/CV cables in drder to prove its reliability. As a result, arc noises, generated from spark gap, were considerably decreased by use of a pneumatic switch immersed into oil, and artificial needle-type defects were well detected with impulse voltage level under $2U_0$. These results imply that it is likely possible to apply SI-PD measurement method as a the nondistructive test for the 22.9 kV CN/CV cable system in Korea.

• Journal of the Korean Society of Tobacco Science
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• v.12 no.2
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• pp.77-83
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• 1990

This study was conducted to develop the method of hydrocarbon analysis and investigate hydrocarbon contents in flue-cured and burley tobacco leaves harvested in Korea and U.S.A. Tobacco leaf was extract with hexane in soxhlet apparatus. Hydrocarbon was fractionated from hexane extract by silica gel column chromatography, and then separated and indentified by GC, GC/MS using SE-54 fused silica capillary column. The developed method was feasible to analyze neophytadiene, normal and branched hydrocarbons from Clo to Cn. The result of recovery test was decade 99%, eicosane 100%, triacontane 102%. The major hydrocarbon of tobacco leaves were neophytadiene, nC3l, iC31, nC33, aC33, aC32, aC30 and nC29. The amount of total hydrocarbon in burley and flue-cured tobacco leaves harvested in U.S.A. and Korea were 4591, 2931, 2929 and 3015$\mu\textrm{g}$/g, respectively.

• Textile Coloration and Finishing
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• v.31 no.3
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• pp.214-224
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• 2019

This investigation reported the simulation technologies to design the 3-dimensional fabrics such as 3 dimensional multi-layered fabric, 3 dimensional braided fabric and spacer fabric. The simulation system or software has been actively used to develop products of 3 dimensional fabric which can be reduced development costs and time. Thus, many countries such as Japan, Germany, China, and U.K. show great interests on simulation technologies for developing new materials and processes including 3 dimensional fabric field. In this study, simulation systems have been reviewed for the 3 dimensional fabric design system from Mikawa Textile Research Center, Japan; ProCad and ProFab from Karl Mayer and Texion, Germany; xComposites from China; TexGen from Nottingham University, U.K.; TexPro from Young Woo CnI, Korea, respectively.

• Archives of Pharmacal Research
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• v.19 no.1
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• pp.62-65
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• 1996

A homologous series of twenty, hitherto unreported, analogues of 5-halosubstituted $1, 3-Bis(\omega-cyanoalkyl)uracil$acyclic nucleosides were synthesized by the series of alkylation reactions of 5-halouracils with the corresponding chloroacetonitrile, chloropropionitrile, chlorobutyronitrile and 5-chlorovaleronitrile $(Cl-(C_ 2)_n-CN: n=l, 2, 3, 4)\; in\; anhydrous\; DMSO\; (or DMF)/K_2CO_3(or NaH)\; under\; 75^{\circ}C$ temperature. Antitumor activities for the synthesized compounds were determined against three cell lines (FM-3A cell, P-388 cell and U-938 cell lines). The compounds that exhibited moderate activity to significant activity, included la-b, 2a-b, 3a-c, and 4a, whose compounds were active against P-388, FM-3A and U-937 cell lines with the compounds la, lb, and 2a, showing significant antitumor activity (inhibitory concentrations $(IC_{50})$ ranged from 2.2 to $7.0\mug/ml$). Their strucrure-activity relationship did not show any activity differences in their effective chain length (methyl, ethyl, propyl, butyl) in 1, 3-bis(.omega.-cyanoalkyl) uracils.

• Journal of the Korean Mathematical Society
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• v.53 no.2
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• pp.381-401
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• 2016

According to Jacobson [31], a right ideal is bounded if it contains a non-zero ideal, and Faith [15] called a ring strongly right bounded if every non-zero right ideal is bounded. From [30], a ring is strongly right AB if every non-zero right annihilator is bounded. In this paper, we introduce and investigate a particular class of McCoy rings which satisfy Property (A) and the conditions asked by Nielsen [42]. It is shown that for a u.p.-monoid M and ${\sigma}:M{\rightarrow}End(R)$ a compatible monoid homomorphism, if R is reversible, then the skew monoid ring R * M is strongly right AB. If R is a strongly right AB ring, M is a u.p.-monoid and ${\sigma}:M{\rightarrow}End(R)$ is a weakly rigid monoid homomorphism, then the skew monoid ring R * M has right Property (A).

• Journal of Photoscience
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• v.9 no.1
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• pp.17-22
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• 2002

Studies have been conducted to explore photoaddition reactions of N-methylthiophthalimide with $\alpha$-silyl-n-electron donors Et$_2$NCH$_2$SiMe$_3$, n-PrSCH$_2$SiMe$_3$ and EtOCH$_2$SiMe$_3$. Photoaddition of $\alpha$-silyl amine Et$_2$NCH$_2$SiMe$_3$ to N-methylthiophthalimide occurs in $CH_3$CN and benzene to produce non-silicon containing adduct in which thiophthalimide thione carbon is bonded to $\alpha$-carbon of $\alpha$-silyl amine in place of the trimethylsilyl group. In contrast, photoaddition of EtOCH$_2$SiMe$_3$ to N-methylthiophthalimide generates two diastereomeric adducts in which thiophthalimide thione carbon is connected to $\alpha$-carbon of $\alpha$-silyl ether in place of u-hydrogen. Based on a consideration of the oxidation potentials of u-silyl-n-electron donors and the nature of photoadducts, mechanism for these photoadditions involving single electron transfer(SET) -desilylation and H atom abstraction pathways are proposed.

• Archives of Pharmacal Research
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• v.17 no.3
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• pp.135-138
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• 1994

Acyclonucleoside homologues of 1-$(\omega$-cyabnoalkyl)-and 1, 3-bis $(\omega$-cyanoalkyl) uracils were synthesized by the series of alkylation reactions of uracil with the $\omega$-chloroalkyl nitrile ${(Cl-(CH}_2)_n$-CN;n=1, 2, 3, 4) in DMSO under $50-70^circ{C}$ temperature. The 1-$(\omega$-cyanoalkyl)-and 1, 3-bis$(\omega$-cyanoalkyl) uracils were separated either by the fractional crystallization or column chromatography. The antitumor activities for these synthesized compounds were determined against four cell lines (J-82 cell, P388 cell, FM-3A cell and U-937 cell lines). These compounds failed to exhibit any significant antitumor activity.

• Korean Journal of Remote Sensing
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• v.2 no.2
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• pp.117-131
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• 1986

The purpose of this study was to develop techniques acquiring hydrologic parameters that affect runoff conditions from Landsat imagery. Runoff conditions in a study area were analyzed by employing the U.S. Soil Conservation Service(SCS) Method. SCS runoff curve numbers(CN) were estimated by the computer analysis of Landsat imagery and digiral terrain model(DTM) data. The SCS Method requires land use/cover and soil conditions of the area as input parameters. A land use/cover map of 5 hydrological classes was produced from the Landsat multi-spectral scannerr imagery. Slope-gradient and contour and contour maps were also made using the DTM topographic data. Inundation areas depending on reservoir levels were able to be mapped on the Landsat scene by combining the contour data.