• Solar Energy
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• v.16 no.2
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• pp.87-96
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• 1996

Electochromic tungsten oxide thin films were prepared on the ITO coated glass by rf magnetron sputtering from a compressed powder tungsten oxide target in an argonoxygen atmosphere. The influence of the preparation conditions, especially the substrate temperature, on the chemical stability of film was investigated. These films were cycled in 0.6M $LiClO_4$ and 0.6M $H_2SO_4$ electrolyte respecitively, and exhibited electrochromic behavior upon the electrochemical insertion and extraction of ion. Among these tungsten oxide thin films, films prepared at a substrate temperature of $150^{\circ}C$ were found to be most stable in terms of cyclic durability.

• YAKHAK HOEJI
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• v.39 no.3
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• pp.306-313
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• 1995

The aim of the present study was to produce low molecular weight cathepsin B inhibitor. A strain of Streptomyces aburabiensis isolated from soil in Korea was selected and the optimum condition for the production of the inhibitor was evaluated. Glucose and soytone were selected as best carbon and nitrogen sources, respectively. From the kinetic analysis in batch fermentation, it was found that the specific cathepsin B inhibitor production rate (q$_{p}$) was linearly related to specific growh rate ($\mu$). The inhibitor in culture filtrate was purified by adsorption on activated charcoal, butanot extraction, silica gel chromatography, ion exchange chromatography using Dowex-1 (Cl form) and Amberlite IRC-50 (H$^{+}$ form), and preparative TLC. From the UV, IR, Mass spectroscopy and $^{1}$H-NMR, the inhibitor was thought to be a new inhibitor of which molecular weight was 199.

• YAKHAK HOEJI
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• v.35 no.5
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• pp.444-455
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• 1991

Two kinds of new lectin fractions (LOA-I, LOA-II) were obtained from loach (Misgurnus spp.) meat by 0.15 M NaCl extraction, salt fractionation, ion exchange and hydroxyapatite column chromatographies. On polyacrylamide gel electrophoresis, LOA-I exhibited one major and a few minor bands, but LOA-II exhibited three minor bands. The partially purified loach lectins agglutinated not only erythrocytes of human B and AB type, rabbit, dog, but also murine splenic lymphocytes. Agglutinability was relatively labile at various pH and stable at increasing temperature, but was not affected by tested several metal ions. By the sugar specificity test, D-glucosamine and metyl-$\beta$-galactopyranose inhibited agglutinating activity at a final concentration of 3 mM. The lectins contained relatively high amounts of aspartic acid, valine and leucine, but sulfur containing amino acids, cystein, methionine and isoleucine were not determined. LOA-I, LOA-II lectins were nonmitogenic toward murine lymphocytes.

• Annual Conference on Human and Language Technology
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• 2000.10d
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• pp.19-25
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• 2000

명사 추출기는 정보검색, 문서분류, 문서요약, 정보추출 등의 분야에서 사용되고 있으며, 정확한 명사 추출과 빠른 색인 속도는 이들 시스템 성능과 밀접한 관계가 있다. 한국어에서 명사를 추출하기 위해서는 형태소 분석이 필요한데, 본 논문에서는 대량의 품사부착된 말뭉치로부터 추출한 분석배제 정보와 후절어를 이용함으로써 형태소 분석을 생략하거나 보다 단순한 처리에 의해 명사를 추출하는 방법을 제안한다. 또한 형태소 분석시 복잡한 음운 현상을 처리하기 위해 많은 음운 규칙을 적용하는 대신 음운 복원 정보를 사용하여 음운 현상을 처리하는 방법을 제안한다. 실험결과에 의하면, 제안된 방법에 의한 명사추출기는 비교적 높은 정확률과 재현율을 나타내며, 빠른 속도를 보였다.

• Archives of Pharmacal Research
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• v.4 no.2
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• pp.85-90
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• 1981

A quantitative GC-MS spectrometric assay was used for the determination of residual N, N-dimethylaniline as a contaminant in commercial penicillin derivatives from various sources. The assay utilizes selective ion focusing to monitor in a GC effluent the molecular ions of DMA generated by electron impact ionization. This method includes dissolution of the sample in alkaline solution, extraction of organic base with cyclohexane and injection into GC-MS with a 3% OV-17 column. Levels of 50 ppb of DMA were easily measured with a coeffecient of varation less than 5 % and recoveries from spiked samples exceeded 97 %. The results of the determinations of DMA in various commercial penicillins were relatively free of this contaminant.

• Archives of Pharmacal Research
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• v.19 no.6
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• pp.566-569
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• 1996

A sensitivity method has been developed for the detection and determination of niflmic acid(NA) in human urine. Samples were extracted with diethylether. Flunixin (FN) was added to the sample prior to extraction as an internal standard. Niflumic acid was converted to its methyl derivative and analyzed by capillary gas chromatography/negative chemical isonization mass spectrometry. Using selected ion monitoring (SIM), the levels of NA down to 5 pg/ml could be detected in 5 ml spiked urine sample. Calibration curve was linear over the range of 0.5 ppm-50 ppm. The recovery of niflumic acid from urine at 40 pg/ml was to be $91.7{\pm}3.8(n=3)$ and the coefficient of variation was 4.1%.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.667-671
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• 2009

Extract of water-soluble polysaccharide (CFWx), showing inhibiting activity on ${\alpha}-glucosidase$, was prepared from the fruiting bodies of Cordyceps militaris by hot-water extraction, and ethanol precipitation. Chemical characteristics of CFWx were as follows: carbohydrate content 30% including 16% of uronic acid; 51% protein content; monosaccharide composition, Man:Glu:Gal (30:43:27); molecular weight $3-5{\times}10^4$. CFWx was further purified by ion-exchange, gel-permeation, and affinity chromatography and $CFWx-AH-{\alpha}$ fraction was isolated. Fundamental structure of $CFWx-AH-{\alpha}$ was deduced as ${\alpha}-(1{\to}4$)-D-glucan with ${\alpha}-(1{\to}3$)- and/or ${\alpha}-(1{\to}6$)-D-glycosidic side chains based on methylation analysis.

• Preventive Nutrition and Food Science
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• v.4 no.4
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• pp.270-275
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• 1999

Radiation-induced hydrocarbons and 2-alkylcyclobutanones are formed from the fatty acids of irradiated fats. Peanuts were irradiated with a dose of 0.1∼10 kGy. The method consists of the extraction of fat from peanuts, separation of hydrocarbons and 2-alkylcyclobutanones with florisil column chromatography and identification of hydrocarbons by the GC/MS method and 2-alkylcyclobutanones by GC/MS/selected ion monitoring (SIM). Concentrations of hydrocarbons and 2-alkylcyclobutanones were linearly increased with the dose levels of radiation. The major hydrocarbons in the irradiated peanut samples were 8-heptadecene and 1,7-hexadecadiene from oleic acid and 6,9-heptadecadiene and 1,7,10-hexadecatriene from linoleic acid. 2-(5'-Tetradecenyl)cyclobutanone, one of 2-alkylcyclobutanones, was the highest amount in the irradiated peanuts. Radiation-induced hydrocarbons in the peanuts were detected at doses of 0.5 kGy and over, and radation-induced 2-alkylcyclobutanones were detected at doses of 1 kGy and over. These compounds were not confirmed in unirradiate peanuts.

• Journal of the Korean institute of surface engineering
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• v.23 no.4
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• pp.218-224
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• 1990

Silicon nitride thin(SiNx) is deposited onto 3 inch silicon wafor using ECR plasma apparatus. For the two different plasma extraction windows size, the thin films which were deposited by changing the SiH4/N2 gas fole at at 1.5mTorr without substrate heating are analyzed through the XPS and wlliposometer measurements. The very uniform and good quality silicon nitride thin film were obtained with the analyzed results of the deposited films, and particularly, ion temperature perpendicular to the magnetic filed was nearly same as the neutral gas temperature. The large amount of plasma loss in the transport process following magnetic field lines could be seen from the plasma emission intensity measurements.

• Analytical Science and Technology
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• v.17 no.1
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• pp.85-89
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• 2004

Fragrance components of lilac (Syringa vulgaris) blossom have been characterized in this paper. The accurate characterization of fragrances collected from lilac blossom was carried out by solid-phase trapping-solvent extraction and gas chromatography-ion trap mass spectrometry. According to lilac species, the chemical compositions were significantly different. Benzaldehyde, phenylacetaldehyde, and ${\alpha}$-farnesene were found as the predominant component of white lilac blossom whereas benzaldehyde, ${\alpha}$-pinene, and ocimene were those of pale purple lilac. The enantiomeric analysis of ${\alpha}$-pinene in lilac blossom was found in the form of ( ).