• Korean Journal of Crystallography
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• v.1 no.2
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• pp.84-90
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• 1990

1,3-Diazatricyclo (5.2.1.Os .to) decane-2,11-dione , C8H10N2O2. MW=166.15, Monoclinic, P2/n a= 6.585(7) , b=9.089(4), c=12.937(10)A, β=95.72(5)˚, V=770.4A3, Z=4, Dc=1.43(4) g/cm3, λ (Mo Ka)=0.7093A, r=1.Ocm-1, T=295˚K, final R=0.037 for 698 unique observed reflections. The compound is the product of the intramolecular (2+2) photocycloaddition of Nl-(w-butenyl)uracil and belongs to a (5.2.1.O5.10) tricyclic system. A pair of molecules related by the inversion symmetry are held together by the strong hydrogen bonding interactions between 02 and H3 of the uracil moiety.

• Journal of the Korean Chemical Society
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• v.12 no.4
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• pp.184-189
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• 1968

Molybdenum chelate compounds have been prepared as new compounds; $MoO(CNS)_3{\cdot}2C_{12}H_8N_2,\;MoO(CNS)_3{\cdot}C_{10}H_8N_2$ and $MoO(CNS){\cdot}2C_9H_6ON$. Properties and configuration of the complexes were studied by chemical and physical method.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.2
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• pp.105-110
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• 2000

The $\alpha$-$Fa_{2}O_{3}/SnO_{2}$ thin film gas sensor was fabricated by APCVD and heat treated. The gas sensitivity to flammable gases ($CH_4$, $H_2$, LPG) was measured. This device was to heat treatment at $400^{\circ}C$, $450^{\circ}C$, $500^{\circ}C$, $550^{\circ}C$, $600^{\circ}C$ for 2 h to enhance the gas sensitivity. The heat treated device at $500^{\circ}C$ for 2 h had the best properties and especially it shows high sensitivity to H2 gas. The sensitivity to gases was studied in the temperature range from lOoC to $300^{\circ}C$ in order to find the optimum detection temperature. In the range of detection from 500 ppm to 10,000 ppm at $175^{\circ}C$ the fabricated device showed that the gas sensitivity to $H_2$ was from 62%~76% and to $CH_4$ was from 16 %~58% and to LPG was from 8%~37 %. The sensitivity difference between heat treated device and as fabricated one was about 10 8 The long-term stability to LPG at 1,000 ppm was converged to sensitivity of 30 %.

• Korean Chemical Engineering Research
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• v.45 no.5
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• pp.455-459
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• 2007

Plasma catalytic methane conversion was carried out in the presence of sol-gel derived $Pt/TiO_2$ catalysts within a dielectric-barrier discharge (DBD) reactor. Plasma-assisted reduction (PAR) was applied to reduce the prepared $Pt/TiO_2$ catalysts in DBD reactor, and prepared catalysts were successively reduced by PAR within 20 min irrespective of the Pt loading and the calcination temperature. The highest methane conversion was 40% when 3 wt% $Pt/TiO_2$ and 5 wt% $Pt/TiO_2$ catalysts were used after calcination at $600^{\circ}C$. The selectivities of light alkanes ($C_2H_6$, $C_3H_8$, $C_4H_{10}$) were highly increased when $Pt/TiO_2$ catalysts were used in DBD reactor.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.12
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• pp.2002-2010
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• 2009

The degradation behavior of berberine is examined using GC-MS to select the fingerprint products that can be used to identify berberine dye in badly faded archaeological textiles. A total of $100^{\circ}C$ thermal and $H_2O_2/UV/O_2$ degradation systems were used to degrade berberine chloride 0.1% solution up to 408 hours. The samples were analyzed using the GC-MS. Dihydroberberine, 2-pteridinamine, 6,7-dimethyl-N-[(trimethylsilyl) oxy]-, and 8-methoxy-11-[3-methylbutyl]-11H-indolo[3,2-c]-quinoline, 5-oxide were detected as the major products of thermal degradation and identified as the fingerprint products for berberine dye at the early stage of degradation. Isobenzofuran-1,3-dione,4,5-dimethoxy-, 9H-fluorene,3,6-bis(2-hydroxyethyl)-,1,3-dioxolo[4,5-g]isoquinolin-5(6H)-one,7,8-dihydro-, and 3-tert-butyl-4-hydroxyanisole were detected as the major products generated by the $H_2O_2/UV/O_2$ degradation and identified as the fingerprint products for berberine dye under severe degradation conditions.

• Food Science and Preservation
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• v.16 no.5
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• pp.636-643
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• 2009

Inactivation by UV-C irradiation of Escherichia coli O157:H7 and Listeria monocytogenes inoculated onto washed carrots was examined. Carrot samples were inoculated with 6-7 log CFU/mL of E. coli O157:H7 or L. monocytogenes, treated with doses of 0, 1, 3, 5, or $10\;kJ/m^2$ UV-C, and stored at $4{\pm}1^{\circ}C$ for 8 d. The populations of E. coli O157:H7 and L. monocytogenes significantly decreased with increasing irradiation dose (p<0.05). In particular, E. coli O157:H7 and L. monocytogenes populations fell significantly by 2.35 and 2.38 log CFU/g at $10\;kJ/m^2$, respectively, compared to control values. UV-C irradiation inhibited color changes and decreased the whiteness index in carrot during storage, compared to controls. Sensory evaluation results showed that UV-C-treated carrots had better sensory characteristics than did the control. Therefore, the results suggest that UV-C irradiation could be useful to improve the microbial safety and sensory qualities of fresh-cut carrots during storage.

• YAKHAK HOEJI
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• v.39 no.6
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• pp.600-609
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• 1995

Studies on the pharmaco-constituents from the leaves of Cercts chinensis which have been used for the treatment of inflammation, contusion, dilated blood, pain of heart and stomach, edema, etc. in Korean folk remedies were carried out. Dried leaves of the plant were extracted with MeOH. The MeOH extract was suspended in distilled water and subsequently fractionated with $Et_{2}O$ and n-BuOH. From the $Et_{2}O$ and n-BuOH fractions, six phenolic compounds were isolated and identified as myricitrin($C_{21}H_{20}O_{12}, {\;}m.p.{\;}199~200^{\circ}$. $4myricetin-3-O-{\alpha}-L-rhamnopyranoside$), kaempferol($C_{15}H_{10}O_{6}, {\;}m.p. 276^{\circ}$), quercetin($C_{15}Ha_{10}O_{7}, {\;}m.p.{\;}313~314^{\circ}$), quercitrin ($C_{21}H_{20}O_{12}, {\;}m.p.{\;}176~178^{\circ}, {\;}quercetin-3-O-{\alpha}-L-rhamnopyranoside$), gallicin ($C_{8}H_{8}O_{5}, {\;}m.p.{\;}202~203^{\circ}$. methyl gallate), gallic acid ($C_{7}H_{6}O_{5}, {\;}m.p.{\;}260~265^{\circ}) through their physico-chemical data and UV, IR, EI-MS, $^{13}C-NMR$, and $^{1}H-NMR$ analysis with authentics.

• Korean Chemical Engineering Research
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• v.49 no.5
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• pp.541-547
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• 2011

Nanorod-clustered $MnO_2$ precursors with ${\alpha}$-, ${\beta}$-, and ${\gamma}$-phases are synthesized by hydrothermal reaction of $MnSO_45H_2O$ and $(NH_4)S_2O_8$. The formation of nanorod-clustered ${\beta}-MnO_2$ is particularly confirmed under the conditions of high reactant concentration and hydrothermal reaction at $150^{\circ}C$. The spinel $LiMn_2O_4$ nanorod-clusters are also prepared by lithiating the $MnO_2$ precursors, varying the concentration of lithiating agent ($LiC_3H_3O_2{\cdot}2H_2O$) and heat treatment temperature, and characterized for use as cathode material of lithium-ion batteries. As a result, the nanorod-clustered $LiMn_2O_4$ prepared from the ${\beta}-MnO_2$ at higher $LiC_3H_3O_2{\cdot}2H_2O$ concentration and the annealing at $800^{\circ}C$ is proven to show the cubic spinel structure and to achieve the high initial discharge capacity of 120 mAh/g.

• Journal of Integrative Natural Science
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• v.8 no.3
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• pp.192-203
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• 2015

In view of the growing medicinal importance of pyrazole and its derivatives, the single crystal X-ray diffraction study was carried out for the potential active 2-Benzyl-3-[3-(4-bromo-phenyl)-1-phenyl-1H-pyrazol-4yl]-4,6-dioxo-5-phenyl-octahydro-pyrrolo[3,4-C]pyrrole-1-carboxylic acid ethyl ester ($C_{37}H_{31}BrN_4O_4$, H2O). In the title compound are two molecules exist in the asymmetric unit. It crystallizes in the monoclinic space group $P{\hat{i}}$ with unit cell dimension $a=13.361(18){\AA}$, $b=13.424(17){\AA}$ and $c=21.649(2){\AA}$ [${\alpha}=80.745(9)^{\circ}$, ${\beta}=79.770(10)^{\circ}$ and ${\gamma}=60.788(6)^{\circ}$]. The pyrazole ring adopts planar conformation. The sum of the bond angles at nitrogen atom of the pyrazole ring indicates the $Sp^2$ hybridized state. The crystal structure is stabilized by intramolecular C-H...O hydrogen bond interaction.

• Journal of the Korean Ceramic Society
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• v.27 no.3
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• pp.361-368
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• 1990

The properties of the powder of ZrO2＋3m/o Y2O3 system prepared by co-precipitation method at the pH values of 7, 9, 10 and 11 were investigated. ZrOCl2.8H2O and YCl3.6H2O were used as starting materials and NH4OH as a precipitation agent. Zirconium hydroxide near by Zr(OH)4 structure showed more excellent crystallinity and lower formation temperature of tetragonal ZrO2. In the range of this study, cubic ZrO2 was not formed and stability of tetragonal ZrO2 prepared in the conditiion of pH 7 was most excellent. Average particle sizes and specific surface areas of tetragonal ZrO2 powders, prepared as calcining amorphous zirconium hydroxides at $600^{\circ}C$ for 1h, were 0.6-0.8${\mu}{\textrm}{m}$ and 45-70$m^2$/g, respectively.