• YAKHAK HOEJI
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• v.36 no.6
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• pp.577-581
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• 1992

Norfloxacin complexes of $Fe^{2+}$, $Cu^{2+}$ and $Al^{3+}$ have been prepared as solids. The stoichiometry of the complexes has been established. IR investigation indicates the metal-ligating sites in norfloxacin. The bioactivities of complexes all lower than that of norfloxacin. The solubilities and partition coefficients have been measured as a function of temperature. The data are used to evaluate the thermodynamic parameters ${\Delta}G$, ${\Delta}H$, ${\Delta}S$ for the solute transfer process and compared with the parent quinolone, norfloxacin. The existence of such complexes is discussed in the light of quinolone mode-of-action theories.

• Journal of the Korean Chemical Society
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• v.41 no.2
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• pp.77-81
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• 1997

The transport rates of transition metal cations were increased in order of Ni(II)$(NtnOenH_4)$and 1,12,15-triaza-3,4;9,10-dibenzo-5,8-dioxacyclo-heptadecane$(NdienOenH_4)$as carriers. The transport rates of transition metal cations was found to be of first order to the salt concentrations. It was also found that the dissociation process in the transport process is rate determining step. From the measurements of the transport rates at various temperatures, the partition free energies of hydration$({\Delta}G_p)$for the transition metal cations were calculated. The results showed that the order of transport rates of transition metal cations was found to be proportional to the magnitudes of negative value of the partition free energies of hydration$({\Delta}G_p)$.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.17 no.2
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• pp.67-85
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• 2013

Reproducing Polynomial Particle Method (RPPM) is one of meshless methods that use meshes minimally or do not use meshes at all. In this paper, the RPPM is employed for free vibration analysis of shear-deformable plates of the first order shear deformation model (FSDT), called Reissner-Mindlin plate. For numerical implementation, we use flat-top partition of unity functions, introduced by Oh et al, and patchwise RPPM in which approximation functions have high order polynomial reproducing property and the Kronecker delta property. Also, we demonstrate that our method is highly effective than other existing results for various aspect ratios and boundary conditions.

• The Korean Journal of Food And Nutrition
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• v.27 no.3
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• pp.532-537
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• 2014

Cortex Phellodendri (CP) is derived from the dried bark of Phellodendron amurense. It has been widely used as a drug in traditional Korea medicine for treating diarrhea, jaundice, swelling pains in the knees and feet, urinary tract infections, and infections of the body surface. Many analytical methods have been used to study oriental herbal medicines, such as thin-layer chromatography, column liquid chromatography, and high performance liquid chromatography (HPLC). In this study, preparative centrifugal partition chromatography (CPC) was successfully carried out in order to separate pure compounds from a CP methanol extract. The optimum two-phase CPC solvent system was composed of n-butanol: acetic acid: water (4:1:5 v/v/v). The flow rate of the mobile phase was 3 mL/min in ascending mode with rotation at 1,000 rpm. The CPC-separated fraction and purification procedures were carried out by preparatory HPLC. The $^1H$ NMR spectrum revealed that the resonances at ${\delta}$ 4.10 and 4.20 ppm corresponded to three protons ($-OCH_3$), whereas those at ${\delta}$ 6.10 ppm corresponded to two protons ($-OCH_2O-$). Further, two aromatic protons (H-11 and H-12) conveys a doublet-doublet pattern. The H-11 doublet and H-12 doublet appear at ${\delta}$ 7.98 and 8.11, respectively. The $^{13}C$ NMR. spectrum showed a tetrasubstituted with a methylenedioxy group at C2 and C3, and two methoxy groups at C9 and C10. The chemical structure of the berberine was identified by $^1H$, $^{13}C$-nuclear magnetic resonance and electrospray ionization-mass spectroscopy spectral data analysis.

• Journal of the Korean Applied Science and Technology
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• v.15 no.4
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• pp.1-9
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• 1998

The lipids from the seeds of Pinus koraiensis mostly composed of triacylglycerols (TGs), in which linoleic acid (46.2 mol%) and oleic acid (25.6 mol%) are present as main components in the fatty acid composition. Surprisingly, they also have unusual fatty acids with ${\Delta}^5$-double bond systems such as ${\Delta}^{5.9.12}-C_{18:3}$ (16.0 mol%), ${\Delta}^{5.9}-C_{18:2}$ (2.3 mol%) and ${\Delta}^{5.11.14}-C_{20:3}$ (0.8 mol%). Saturated fatty acids of palmitic, stearic and arachidic acid were present in less than 8.0 mol%. TG was resolved into 17 fractions by reverse-phase HPLC according to so-called partition number (PN) suggested by Plattner, in which TG molecules with ${\Delta}^{5}$-NMDB acyl chains eluted later than did those with ${\Delta}^{9}$-MDB acyl radicals. $Ag^+$-HPLC separated the TG into 14 fractions more clearly than did those with ${\Delta}^{9}$-MDB acyl radicals. $Ag^+$-HPLC separated the TG into 14 fractions more clearly than did reverse-phase HPLC, and the complexity of ${\Delta}^{5.9.12}-C_{18:3}$ moiety with silver ion impregnated in the column bed was in the level between ${\Delta}^{9.12.15}-C_{18:3}$ ($C_{18:3{\omega}3}$) and $C_{18:2{\omega}6}$ (${\Delta}^{9.12}-C_{18:2}$). In the $Ag^+$-HPLC, it was found that the molecular species having a given-numbered double bonds widely spreaded in the acyl chains eluted earlier than those concentrated in one acyl chain. The main molecular species are $(C_{18:2{\omega}6})_2/{\Delta}^{5.9.12}-C_{18:3}$ (14.8 mol%), $C_{18:1{\omega}9}/C_{18:2{\omega}6})_2$ (12.8 mol%) and $C_{18:1{\omega}9}/C_{18:2{\omega}6}/{\Delta}^{5.9.12}-C_{18:3}$ (10.9 mol%).

• Textile Coloration and Finishing
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• v.15 no.5
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• pp.316-320
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• 2003

In order to investigate the dyeing property of poly trimethylene terephthalate(PTT) fabric, the dyeing of PTT fabric was carried at under condition of different dyeing temperature by using several disperse dyes with different energy level. Particularly, this study discussed the PTT dyeing thermodynamically. Used disperse dyes were selected based on the their chemical structure and energy level. The obtained results were as followings; The dye adsorption of S type disperse dye such as C. I. Disperse Blue 79 increased with increasing dyeing temperature. In a exhaustion rate of PTT fabric with disperse dyes, C. I. Disperse Blue 56 showed higher values than that of C. I. Disperse Orange 29 and Blue 79. For the interpretation of thermodynamic dyeing behavior, the partition coefficient ( K ) and some several thermodynamic parameters such as standard affinity$(-\mu^\circ)$ and heat of dyeing$(\Delta{H}^\circ)$ calculated from the adsorption isotherm. From above results, as the energy level of disperse dye is small, the partition coefficient and standard affinity increased. But the heat of dyeing of PTT fabric with disperse dye showed high negative value in order of E type(C. I. Disperse Blue 56), SE type(C. I. Disperse Orange 29) and S type(C. I. Disperse 79).

• Journal of the Korean Applied Science and Technology
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• v.14 no.1
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• pp.61-76
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• 1997

Triacylglycerols of the seeds of Ginkgo biloba have been resolved by high-performace liquid chromatography(HPLC} in the silver-ion and reverse-phase modes. The fatty acids were identified by a combination of capillary gas chromatography and gas-chromatography /mass spectrometry as the methyl and /or picolinyl ester. The main components are $C_{18:2{\omega}6}$(39.0mol%), $C_{18:1{\omega}7}$(asclepic acid 21.5mol%), and $C_{18:1{\omega}9}$(oleic acid, 13.8mol%). Considerable amounts of unusual acid such as $C_{20:3{\Delta}^{5,11,14}$ (5.7mol%), $C_{18:2{\Delta}^{5,9}$(2.8mol%), and $C_{18:3}{\Delta}^{5,9,12}$(1.6mol%), were checked. In addition, an anteiso-branched fatty acid, 14-methylhexadecanoic acid, was also present as a minor component(0.9 mol%). The triacylglycerols were separated into 17 fractions by reverse-phase HPLC, and the fractionation was achieved according to the partition numnber(PN) in which a ${\Delta}^5$-non methylene interrupted double bond($^5$-NMDB) showed different behaviour from a methylene interrupted double bond in a molecule with a given cahinlength. Silver-ion HPLC exhibited excellent resolution in which fractions(23 fractions) were resolved on the basis of the number and configuration of double bonds. In this instance, the strength of interaction of a ${\Delta}^5$-NMDB system with silver ions seemed to be weaker than a methylene interrupted double bond system. The principal triacylglycerol species are as follows ; $(C_{18:2{\omega}6)2}/C_{18:1{\omega}7}$, $C_{18:1{\omega}9}/C_{18:1{\omega}7}/C_{18:2{\omega}6}$, $(C_{18:1{\omega}7)2}/C_{18:2{\omega}6}$, $C_{16:1{\omega}7}/C_{18:1{\omega}9}/C_{20:3}{\Delta}^{5,11,14}$, $C_{16:1{\omega}7}/C_{18:1{\omega}7}/C_{20:3}{\Delta}^{5,11,14}$, $C_{18:1{\omega}9}/C_{18:1{\omega}7}/C_{18:2{\omega}6}$, $C_{18:1{\omega}9}/C_{18:2}{\Delta}^{5,5}/C_{20:3}{\Delta}^{5,11,14}$, $(C_{18:1{\omega}7)2}/C_{18:2{\omega}6}$ and $(C_{18:1{\omega}9)2}/C_{18:2{\omega}6}$, while simple triacylglycerols without $C_{18:2{\omega}6})_3$ were not present. Stereospecific analysis showed that fatty acids with ${\Delta}^5$-NMDB system and saturated chains were predominantly located at the site of sn-3 carbon of glycerol backbones. It is evident that there is asymmetry in the distribution of fatty acids in the TG molecules of Ginkgo nut oils.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2008.04a
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• pp.172-176
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• 2008

In this paper, three dimensional linear conforming variable-finite elements are presented with the aid of a smoothed integration (a class of stabilized conforming nodal integration), for mnltiscale mechanics problems. These elements meet the desirable properties of an interpolation such as the Kronecker delta condition, the partition of unity condition and the positiveness of interpolation function. The necessary condition of linear exactness is fully relaxed by employing the smoothed integration, which renders us to meet the linear exactness in a straightforward manner. This novel element description extend the category of the conventional finite elements space to ration type function space and give the flexibility on the number of nodes of element which are fixed in the conventional finite elements. Several examples are provided to show the convergence and the accuracy of the proposed elements, and to demonstrate their potential with emphasis on the multiscale mechanics problems such as global/local analysis, nonmatching contact problems, and modeling of composite material with defects.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2021.06a
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• pp.361-362
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• 2021

본 논문에서는 VVC(Versatile Video Coding) 부호화 시간 감소를 위해 ISP(Intra Sub-Partition) 모드의 복잡도를 감소시키는 방법을 제안한다. 이 방법은 ISP 모드 적용을 위한 RDO(Rate-Distortion Optimization) 탐색을 수행할 때 현재 블록의 모양에 따라 특정 ISP 모드 방향을 사전에 제한하여 RDO 과정을 생략함으로써 부호화 시간을 단축한다. 실험 결과, 기존 VVC 방법 대비 BDBR(Bjøntegaard Delta Bit Rate) 측면에서 AI(All Intra) 구성하에 Y 채널에서 0.01%, Cb, Cr 채널에서 각각 -0.04%, -0.08% 변화로 2%의 부호화 시간 감소의 결과를 얻을 수 있었다.

• Bulletin of the Korean Chemical Society
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• v.25 no.2
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• pp.271-279
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• 2004

The aroma component of Hallabong peel has been characterized by GC-MS with two different extraction techniques: solid-phase trapping solvent extraction (SPTE) and headspace solid-phase microextraction (HSSPME). Aroma components emitted from Hallabong peel were compared with those of other citrus varieties: lemon, orange and grapefruit by SPTE and GC-MS. d-Limonene (96.98%) in Hallabong was the main component, and relatively higher peaks of cis- ${\beta}$-ocimene, valencene and -farnesene were observed. Other volatile aromas, such as sabinene, isothujol and ${\delta}$-elemene were observed as small peaks. Also, principal components analysis was employed to distinguish citrus aromas based on their chromatographic data. For HSSPME, the fiber efficiency was evaluated by comparing the partition coefficient ($K_{gs}$Kgs) between the HS gaseous phase and HS-SPME fiber coating, and the relative concentration factors (CF) of the five characteristic compounds of the four citrus varieties. 50/30 ${\mu}$m DVB/CAR/PDMS fiber was verified as the best choice among the four fibers evaluated for all the samples.