• Journal of the Korean Wood Science and Technology
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• 제35권5호
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• pp.93-99
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• 2007

Paulownia coreana inner bark was collected, extracted in 70% acetone, concentrated under reduced pressure and sequentially fractionated using n-hexane, $CH_2Cl_2$, EtOAc and $H_2O$, then freeze dried to give brown powders. A portion of the EtOAc soluble powder was chromatographed on a Sephadex LH-20 column using a serious of aqueous methanol and ethanol-hexane mixture as eluting solvents. Two phenolic acid, $\rho$-courmaric acid and caffeic acid, two isomeric phenylethanoid glycosides, verbascoside and iso-verbascoside, and one epimeric phenylpropanoid glycoside, cistanoside F, were isolated and their structures were elucidated by spectroscopic analysis such as NMR and MS.

• Advances in Traditional Medicine
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• 제8권4호
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• pp.374-379
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• 2008

In the present study, various extracts of Clerodendrum infortunatum leaves have been studied for its anthelmintic, antimicrobial and antipyretic activities. In the anthelmintic and antipyretic study it was observed that the benzene extract was more potent than the other two extracts (ethanol and aqueous) even though all the three extracts were endowed with both the properties. The study reveals antimicrobial activity of the extracts against the tested strains of microorganisms between concentration ranges of $75\;{\mu}g/ml$ and $350\;{\mu}g/ml$ and shows effectiveness more against gram-positive bacteria than the gram-negative bacteria.

• Fibers and Polymers
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• 제2권2호
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• pp.58-63
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• 2001

Silk fibroin (SF) was dissolved in calcium chloride/ethanol/water mixture(1/2/8 in mole ratio) at $70^{\circ}C$ for 4h. The dissolved silk fibroin was regenerated by casting the dialyzed solution into films. The films were treated with 50% aqueous solution of methanol for different times, and their antithrombogenicity was evaluated by in vivo tests. In vivo blood tests were made by a method of peripheral vein indwelling suture. It was found that the silk fibroin had a good antithrombogenicity and an absorbability even though the polymer showed foreign body reaction. Finally, the blood compatibilty of silk fibroin films which were subjected to structural change by the methoanl treatment, was examined in connection with their interfacial surface energy, and a correlation between these properties was found to be present.

• 약학회지
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• 제37권3호
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• pp.209-215
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• 1993

Basic drugs could be extracted as ion-paired complexes with Lumogallion, Superchrome Garnet Y and their alkyl derivatives from aqueous acid solution, and then determined fluoro-metrically after addition of aluminum ion. The analysis was carried out as follows; To a 1 ml portion of basic drugs (10$^{-9}$~2$\times$0$^{-8}$mole/ml), 1ml of 0.01w/v% fluorescent reagent solution, and 10ml of dichloroethane are added. The mixture is stirred for 1 minute. After standing for a few minutes, the dichloroethane layer is transfered to 1 ml of 0.1w/v% Al(NO$_{3}$)$_{3}$ ethanol solution. After mixing, and standing for 30 minutes at room temperature, the fluorescence intensity is measured with each maximum excitation and emission wavelength. The reagent blank is run through the whole procedure. From the degree of enhancement of fluorescence intensity, hexyl and dodecyl lumogallion and Superchrome Garnet Y were judged to be the useful one of fluorescent reagent for basic drugs analysis.

• Elastomers and Composites
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• 제52권2호
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• pp.131-135
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• 2017

Zinc nitrate hexahydrate [$Zn(NO_3){\cdot}6H_2O$] and sodium hydroxide [NaOH] were used as source reagents in the preparation of ZnO nanoparticles in an aqueous solution containing deionized water and ethanol in a ratio of 2:5 (v/v). ZnO nanoparticles were heated in an electric furnace at $700^{\circ}C$ for 2 h under an atmosphere of inert argon gas. The morphological and structural properties of the nanoparticles were characterized by scanning electron microscopy (SEM) and powder X-ray diffractometry (XRD). UV-vis spectrophotometry was used to analyze the photocatalytic degradation of 3-nitrophenol with ZnO nanoparticles as photocatalyst under ultraviolet irradiation at 254 nm. Evaluation of the kinetic of the photo-catalytic degradation of 3-nitrophenol indicated that the degradation of 3-nitrophenol with ZnO nanoparticles obeyed the pseudo-first order reaction rate model.

• Journal of Ginseng Research
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• 제22권3호
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• pp.211-215
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• 1998

A rapid separation of an edible panaxadiol (PD) and panaxatriol (PT) in ginseng saponins has been investigated by benzene ethylene resin adsorption method. Briefly, powdered red ginseng was extracted with water. The obtained ginseng extract were dissolved in suitable volume of distilled water, and adsorbed on the benzene ethylene resin with 200 folds water of the resin weight. Sugars and hydrophilic character compounds not absorbed were washed with water, and eliminated by 10-fold water of the resin weight. An edible panaxadiol and panaxatriol can be perfectly separated from ginseng saponins with the fractions below 40% aqueous ethanol and over 45% as an fluent.

• Preventive Nutrition and Food Science
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• 제10권3호
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• pp.267-271
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• 2005

Many of plants had been reported having immunostimulating activity. This study reports the immunostimulating activity of Cassia tora L. (Leguminosae) seed, by means of solvent extraction method. Ethanol extract and solvent fractions, n-hexane, chloroform, ethylacetate, n-butanol and aqueous layer of Cassia tora L. seed were tested for immunostimulating activity in vitro. The ethylacetate-soluble fraction caused significant inhibition on the production of nitric oxide by murine macrophages (RAW 264.7), and mouse splenocytes were also stimulated at the concentration of 10 pgfmL. Three anthraquinones, chrysophanol (1), isochrysophanol (2) and aloe-emodin (3) with immunostimulating activity were isolated from the ethylacetate-soluble fraction of Cassia tora L. seed through activity-monitored fractionation and isolation method. These results permit Cassia tora L. to be useful as one the of natural immunostimulating crops.

• 대한화학회지
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• 제32권6호
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• pp.567-574
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• 1988

바나듐(IV)촉매가 존재하는 물 및 알코올 수용매에서 과산화수소에 의한 디메틸술폭시드의 산화반응은 디메틸술폭시드와 산농도에 각각 일차의존성임을 보여주었다. 이 산화반응의 속도 결정단게는 황이 바나듐(V)-과산화물의 O-O결합에 대하여 친핵적 공격을 함으로서 디메틸술폭시드가 산화되는 과정임을 제시한다.

• 통합자연과학논문집
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• 제2권3호
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• pp.207-210
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• 2009

Multiple rugate structures can be etched on a silicon wafer and placed in the same physical location, showing that many sharp spectral lines can be obtained in the optical reflectivity spectrum. Porous silicon samples were prepared by electrochemical etch of heavily doped p-type silicon wafers. The etching solution consisted of a 3:1 volume mixture of aqueous 48% hydrofluoric acid and absolute ethanol. Galvanostatic etch was carried out in a Teflon cell by using a two-electrode configuration with a Pt mesh counterelectrode. A sinusoidal current density waveform varying between 51.5 and $74.6mA/cm^2$ is applied. The anodization current was supplied by a Keithley 2420 high-precision constant current source which is controlled by a computer to allow the formation of PSi multilayer.

• 대한화학회지
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• 제11권4호
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• pp.173-178
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• 1967

强酸性溶液 中에서 ${\beta}$-4-Nitroazoxybenzene이 4-Hydroxy-4'-Nitroazobenzene으로 轉位하는 反應을 UV 分光光度法에 의하여 確認하였다. 20Vol%의 알코올과 80Vol.%의 여러가지 농도의 황산수용액에서의 이 轉位反應 反應速度을 究明하였으며, 그 結果 이 反應이 酸觸媒에 의한 擬1次反應임을 알았으며, 또한 이 轉位反應의 機構도 考察하였다.