• Analytical Science and Technology
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• v.12 no.1
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• pp.1-6
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• 1999

Copper(II) complex of piperidine dithiocarbamate (Pipdtc) was synthesized from the reaction of Cu(II) and piperidine dithiocarbamate. The possible structure of the complex was proposed on the basis of elemental analysis, molar conductivity, infrared spectroscopy, electronic absorption spectroscopy, and $^{13}C-NMR$ studies. The extraction of copper(II)-Pipdtc complex by carbon tetrachloride can be achieved in the pH range of 6.0~10. The solution of copper(II) with piperidine dithiocarbamate was bey Beer's law in the concentration up to ${\sim}8.0{\times}10^{-5}M$ at pH 9.0.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.238-243
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• 2006

The methanol extract of waxy brown rice fermented with Agrocybe cylindracea was prepared. The extract was then freeze dried and fed to rats at the level of 0.5, 1.0, 2.0 g/kg body weight for 14 days, followed by the treatment with carbon tetrachloride for three consecutive days to induce hepatotoxicity. After sacrificing the rats, the enzyme activity of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), and ${\gamma}$-glutamyl transpeptidase (${\gamma}$-GTP) in serum was determined. Biochemical analysis on serum for albumin, total protein, triglyceride, and total as well as HDL-cholesterol were carried out along with a histopathological study of liver tissues. Based on these data, we suggest that the waxy brown rice cultured with A. cylindracea may exert hepatoprotective activity against hepatotoxicity caused by chemicals such as carbon tetrachloride.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.4
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• pp.261-268
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• 1999

Laser-induced thermochemical etching has been recognized as a new powerful method for processing a variety of materials, including metals, semiconductors, ceramics, insulators and polymers. This study presents characteristics of direct etching for Si substrate using focused argon ion laser beam in aqueous KOH and $CCl_2F_2$ gas. In order to determine process conditions, we first theoretically investigated the temperature characteristics induced by a CW laser beam with a gaussian intensity distribution on a silicon surface. Major process parameters are laser beam power, beam scan speed and reaction material. We have achieved a very high etch rate up to $434.7\mum/sec$ and a high aspect ratio of about 6. Potential applications of this laser beam etching include prototyping of micro-structures of MEMS(micro electro mechanical systems), repair of devices, and isolation of opto-electric devices.

• Biomolecules & Therapeutics
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• v.6 no.3
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• pp.261-268
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• 1998

Propolis is a lipophilic, natural product prepared by mixing the exudates collected from various plants by honeybees with beeswax for the purpose of using to seal hive walls and to strengthen the borders of combs. Because of its versatile bioactivities, propolis has been attracting many investigators'interest. But the pharmacological studies on propolis has, to date, been exclusively performed for an alcohol extract, there is few information of water extract. Therefore, in this study, we investigated the various effects of water extract of Chinese propolis. The water extract of propolis and its fractions of organic solvents showed strong antioxidative activities, especially ether and ethylacetate fractions, and reduced the lipid peroxidation of rat liver in viro. Additionally the ether fraction of propolis (10 mg/ml) inhibited the activity of hyaluronidase by 50%. In vivo, the water extract of propolis considerably decreased s-GOT, s-GPT and s-LDH activities which represent for the hepatotoxicity induced by $CCl_4$ in rats, and prolonged the MST (Medium revival tinge) and ILS (Increasing in MST over control) by 18% in mice which inoculated with sarcoma 180 ascites cells. These results suggest that the water extract of propolis has various bioactivities as well as the alcohol extract.

• Korean Journal of Pharmacognosy
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• v.27 no.3
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• pp.196-206
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• 1996

In order to characterize the chemical change, of the constituents and pharmacological transformation of Glycyrrhizae Radix(GR) which may occur during its processing, processed GR has been investigated in comparison with unprocessed GR. It was found that glycyrrhizin(GL) and other several constituents contained in GR were remarkably changed by processing, and the decrease of contents of GL was identified by making use of thin layer chromatography-chromatoscanner. And also, it was found that glycyrrhetic acid (GA) was identified from processed GR. We recognized that commonly processed GR showed less hemolytic effect than unprocessed GR and processed GR at $190{\circ}c$. It was also found that commonly processed GR showed more effective analgesic effect and prolonged the duration of hypnosis induced by pentobarbital-Na in mice as compared with corresponding unprocessed GR and processed GR at $190{\circ}c$. And then, commonly processed GR significantly suppressed the increases of s-GOT, s-GPT and s-LDH activities in injured mice induced by $CCl_4$.

• Journal of Life Science
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• v.11 no.6
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• pp.574-581
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• 2001

This study was performed to evaluate the inhibition effects of fermented soybean on lipid perosidation and antioxidative relative enzyme activity. in vivo. Fermented soybean was induced the high SOD activity, while significantly inhibited on the peroxide value of linoleic acid and lipid perxidation from rat microsome induced by Fe$^{2+}$ ascorbate system, Sprague-Dawley(SD) male rats were fed basic diet, and experimental diets group added 200 or 500 mg/kg fermented soybean for 2 weeks. The effect of fermented soybean is also significantly increased catalase and glutathione peroxidase activities, while significantly inhibited the lipid peroxidation of rat liver microsome in a dose dependent manner. Therefore, these results suggest that fermented soybean has antioxidative activity which is related enzyme to prevention of oxidative stress.s.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.112-112
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• 1995

간장 손상시에는 여러 혈청의 효소 활성과 함께 혈청 $\beta$-glucuronidase의 활성도 증가한다는 것이 보고되었으나 심한 간부전이나 간암의 경우 이들의 활성은 오히려 정상치보다 감소하는 것으로 나타났다. Silymarin은 간장 보호효과로 이미 임상에 널리 사용되고 있는 약물로서 김 등에 의해 silymarin이 장내세균의 $\beta$-glucuronidase와 간장의 $\beta$-glucuronidase의 활성을 억제한다는 것이 보고되었다. 이에 연자 둥은 $\beta$-glucuronidase의 저해 효과가 관찰된 영지버섯온 유기용매로 분획하여 간장 보호효과를 검색하였다. 영지버섯의 70% MeOH 추출물(GT)과 그 ether 분획(GE)에 대해 생쥐 1군을 6마리로 하여 20% $CCl_4$0.1$m\ell$/10g(olive oil로 희석)을 경구투여 하였다. 검액 GE는 50mg/kg과 250mg/kg, GT는 100mg/kg과 500mg/kg을 각각 사염화탄소 투여 30분 전에 경구투여 하였으며 사염화탄소를 투여하고 24시간 후에 심장 채혈하고 혈청을 분리하여 혈청성분 및 혈청효소의 활성을 측정하였다. 대조군에는 생리식염수를 투여하였고 양성 비교약물로는 silymarln 100mg/kg을 경구투여 하여 비교 관찰하였다. 실험 결과, 영지버섯의 ether 분획에서는 혈청중 GOT, GPT의 활성과 triglyceride의 함량에 대해 silymarin보다 우수한 효과를 보였으며, 70% MeOH 추출물은 silymarin에 미치지 못했다.

• Journal of the Korean Chemical Society
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• v.36 no.1
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• pp.100-106
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• 1992

The fluorescence characteristics of copolymers of styrene-maleic anhydride(PSMAn), styrene-maleic acid (PSMA), and PSMA complexed with $Eu^{3+}$ (PSMA-Eu) in tetrahydrofuran were studied. The excimer of PSMA and PSMA-Eu with 75% mole fraction of styrene appears to have larger binding energy than that with 50% or 67% styrene. The ratio of excimer to monomer intensities showed little change with the increase of styrene concentration up to $8.0{\times}10^{-3}M$, indicating the excimer formation is due to intramolecular process. Three existing mechanisms for intramolecular excimer formation are considered inadequate to explain the observed behavior. The quenching of excimer intensity by benzyl-acetate, mesitylene, and $CCl_4$ is interpreted in terms of the molar volume of quencher.

• Journal of the Korean Chemical Society
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• v.9 no.2
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• pp.88-95
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• 1965

The exo adduct between furfuryl derivatives (furan, furfuryl acetate and furfuryl alcohol) and maleic anhydride were prepared in the presence of ethyl ether. The bromination of the exo adduct of each derivatives gave a monobromolactone and dibromoacid when the reaction was done in the presence of water. The formation of the bromolactone was proved to be dependent to the carboxylic participation to the incipient rearranged carbonium ion of a classical type, and the participation was sterically hindered by the steric structure of the substituents. The bromination of the furan-maleic anhydride adduct in the presence of organic solvent $(CCl_4,\;CH_2Cl_2)$ gave the dibromide, whereas the photochlorination of the same adduct in the presence of carbon tetrachloride gave the tetrachloride. The procedure of the preparation and the reaction path of the halogenation were described.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.569-573
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• 2013

In this study, activated carbon fabric was prepared from a cellulose-based polymer (viscose rayon) via a combination of physical and chemical activation (mixed activation) processes by means of $CO_2$ as a gasifying agent and surface and adsorption properties were evaluated. Experiments were performed to investigate the consequence of activation temperature (750, 800, 850 and $925^{\circ}C$), activation time (15, 30, 45 and 60 minutes) and $CO_2$ flow rate (100, 200, 300 and 400 mL/min) on the surface and adsorption properties of ACF. The nitrogen adsorption isotherm at 77 K was measured and used for the determination of surface area, total pore volume, micropore volume, mesopore volume and pore size distribution using BET, t-plot, DR, BJH and DFT methods, respectively. It was observed that BET surface area and TPV increase with rising activation temperature and time due to the formation of new pores and the alteration of micropores into mesopores. It was also found that activation temperature dominantly affects the surface properties of ACF. The adsorption of iodine and $CCl_4$ onto ACF was investigated and both were found to correlate with surface area.