• Proceedings of the Korean Nuclear Society Conference
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• 2002.05a
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• pp.420.1-420
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• 2002

Thermal decomposition reaction of gas-phase UO2(hfacac)2. THF was investigated in a static cell. IR spectroscopic method was used to study the thermal decomptsition of gas phase uranyl complexes. The decomposition reaction products were separated by using thermal-gradient fractional sublimation method utilizing the differences in their volatility.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.332-333
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• 2001

Genomic DNA was extracted from the blood of the freshwater crucian carp(Carassius carassius) from Kunsan in Korea, representing genetic similarity by polymerase chain reaction amplification of DNA as twelve of arbitrary primers. The electrophoretic analysis of polymerase chain reaction-random amplified polymorphic DNAs(PCR-RADP) products showed the high levels of similarity between different individuals in crucian carp.

• Bulletin of the Korean Chemical Society
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• v.21 no.9
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• pp.901-904
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• 2000

The mechanism for the photo-Fries rearrangement of phenyl acetate andbiphenylyl acetates were reinvestigat-ed in phenol (or phenol derivatives) containing media. The results showed that the phenol (or phenol deriva-tives) which is the most common by-product of Fries reaction reacts with acyl radical togive Fries-product. These phenol (or phenol derivatives) contributions to the Fries-products were suggested as the Trivial mecha-nism for the photo-Fries reaction.

• Archives of Pharmacal Research
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• v.18 no.1
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• pp.27-30
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• 1995

The Hantzsh reaction of 7-hydroxy-8-methoxy-2-oxo-2H-benzopyran-6-carboxaldehyde (1) with ethyl acetoacetate and ammonia yields the dihydropyridine derivative 2 together with the pyridine derivative 3 and the eight membred ring derivative 4. Reaction of 1 with ethyl cyanoacetate and malononitrile gives the iminodicoumarin derivatives 5 and 6 respectiely. The latter compound was reacted with butan-2-one and acetophenone to produce the Michael adduct 71, b and the 2-aminopyridine derivatives 8a, b.

• Korean Journal of Oriental Medicine
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• v.1 no.1
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• pp.471-476
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• 1995

Natural products used for oriental medicine often come from various geographical sources, after several different distribution channels. Therefore some form of quality control procedure is required to safeguard naturl products for prescriptions purposes. To achieve this, systematic apprroaches such as morphological examination, microscopic analysis of powdered herbs and chemical analysis can be carried out. However, to ensure absolute criteria for quality assurance of natural products, DNA fingerprinting method such as RAPD(Random amplified polymorphism DNA) analysis can be used for authentication of natural products for authenticatin of natural products. In this study, warious oligonucleotide primers will be synthesized for the detection of RAPD markers and also parameters of affecting PCR(Polymerase Chain Reaction) in the detection of RAPD markers of rare and high-priced natural products will be studied with genomic DNA of chosen samples.

• International Journal of Concrete Structures and Materials
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• v.18 no.2E
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• pp.125-132
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• 2006

Waste glass has been increasingly used in industrial applications. One shortcoming in the utilization of waste glass for concrete production is that it can cause the concrete to be weakened and cracked due to its expansion by alkali-silica reaction(ASR). This study analyzed the ASR expansion and strength properties of concrete in terms of waste glass color(amber and emerald-green), and industrial by-products(ground granulated blast-furnace slag, fly ash). Specifically, the role of industrial by-products content in reducing the ASR expansion caused by waste glass was analyzed in detail. In addition, the feasibility of using ground glass for its pozzolanic property was also analyzed. The research result revealed that the pessimum size for waste glass was $2.5{\sim}1.2mm$ regardless of the color of waste glass. Moreover, it was found that the smaller the waste glass is than the size of $2.5{\sim}1.2mm$, the less expansion of ASR was. Additionally, the use of waste glass in combination with industrial by-products had an effect of reducing the expansion and strength loss caused by ASR between the alkali in the cement paste and the silica in the waste glass. Finally, ground glass less than 0.075 mm was deemed to be applicable as a pozzolanic material.

• Applied Chemistry for Engineering
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• v.16 no.4
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• pp.513-518
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• 2005

The co-pyrolysis characteristics of poly(vinyl chloride) (PVC) and polystyrene (PS) mixtures with ZnO have been studied by thermogravimetry (TG) and gas chromatograph-mass spectrometry (GC-MS) under various mixing ratios and reaction temperatures. From this work, it was found that the yield of liquid products increased as PS in mixtures increased, whereas that of gaseous products decreased. And as ZnO in mixtures increased, the yields of gaseous products and HCI decreased. The optimal reaction temperature for the maximum yield of liquids products and the control of HCI gas was $500^{\circ}C$.

• Korean journal of food and cookery science
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• v.18 no.6
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• pp.603-612
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• 2002

The study was carried out to compare the relation between the color intensity and antioxidant activity of caramelization products using xylose(XY), glucose(GL). sucrose(SU), glucose＋citric acid(GLCA), glucose＋sodium citrate(GLSC), heated at 80, 120 and 140$\^{C}$ for 24hrs, respectively. The color intensity(absorbance at 490nm) of the browning mixtures increased as the browning temperature and time increased. But the degrees of color intensity of SU and GLCA changed very little. The hydrogen donating ability(HDA) of browning reaction products was generally enhanced as the browning temperature and time increased. When browning mixtures were heated at 80$\^{C}$, the HDA of GLGC was the highest, but the HDA of GLSC was the highest when heated at 120 and 140$\^{C}$. The antioxidant activities for the corn oil substrate containing the anhydrous ethanol extracts from the browning mixtures was inferior to that of SU, but was superior to that of GLCA. The relations among the color intensity, the antioxidant activity, and the hydrogen donating ability(HDA, reducing power) of the browning reaction mixtures were as follows: As the color intensity increased, the antioxidant activity decreased. The correlation coefficient of the color intensity and the antioxidant activity by regression equation was -0.73 ∼ -0.82. As the reducing power increased, the antioxidant activity decreased. The correlation coefficient between the reducing power and the antioxidant activity by regression equation was -0.98 ∼ -0.99. Therefore, the antioxidant activity of browning reaction mixtures seemed not correlated with the color intensity and the reducing power.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.4
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• pp.273-281
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• 1987

In this work the antioxidant effects of browning reaction products prepared by xylose-tryrtophan reaction system were discussed. The antioxygenic brown pigments were separated by solvent extraction, and column chromatography and isolated by gel filteration. The functional groups of the brown pigments which had antioxidant activity were examined. The brown pigments extracted with methanol showed antioxidant effect and were fractionated in 5portions on DEAE-cellulose column. The elutes with methanol: acetic acid(10:30 v/v sol n(A), methanol: chloroform(95:5 v/v) sol n(C), and chloroform: acetic acid(10:30 v/v) sol n(E) only showed antioxidant activity and their compositions were 22.43, 21.51 and $34.43\%$ respectively. When each fraction on DEAE-cellulose column was reseparated on Sephadex LH-20 column, 2 fractions were obtained from portion A and C respectively. Molecular weights of A, C and E fraction of brown pigments were from 2,600 to 3,700. By elucidation of IR spectra, the pigment fractions which showed a strong antioxidant activity were tearing the indole group. It is suggested that the antioxidant function of the brown pigment is due to hydroxy and amino group. A higher activity of the brown pigment fraction E might be attributed to carboxylic acid or carboxylic ester compounds.

• Korean Journal of Veterinary Research
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• v.34 no.1
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• pp.115-125
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• 1994

In this study, we try to establish the rapid and specific detection system for Salmonella species. The PhoE gene of Salmonella species was amplified with two specific primers, ST5 and ST8c, using PCR. The probe prepared from the amplified PhoE gene was sequenced and applied for Southern blot analysis. After PCR with ST5 and ST8c primers for PhoE gene, DNA bands of expected size(365bp) from 7 different Salmonella species were detected, but not from 12 enterobacteriaceae and 3 gram positive bacteria. PCR was highly sensitive to detect up to 10fg of purified DNA template and to identify Salmonella species with only 320 heat-lysed bacterial cells. The inhibition of PCR amplification from stool specimen was occurred with 50-fold dilution but disappeared over 100 fold dilution of samples. It was confirmed that the PhoE genes were amplified and cloned with over 97% nacleotide sequence homology of PCR products compared with that of S. typhfmurium LT2. The DNA probe derived from S. typhimurium TA 3,000 showed highly specific and sensitive reaction with PCR products of all tested Salmonella species. These results indicate that PCR was rapid and sensitive detection method for Salmonella species and DNA probe prepared from S. typhimurium TA 3,000 was specific to identify PCR products of different Salmonella species.