• Journal of the Korean Magnetics Society
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• v.13 no.4
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• pp.171-175
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• 2003

Electron paramagnetic resonance (EPR) of Fe$^{3+}$ in LiTaO$_3$ single crystal, grown by Czochralski method, has been studied by employing an X-band spectrometer. Resonance spectra of Fe$^{3+}$ ion on the crystallographic principal axes were obtained with 9.447 ㎓ at room temperature. The spectroscopic splitting parameter g and zero-field splitting (ZFS) parameter D (= 3 B$_{2}$sup 0/) are calculated with effective spin Hamiltonian. Fe$^{3+}$ center in stoichometric single crystal turns out to be different with that in congruent single crystal reported previously. From the analysis of temperature dependence of resonance fields for Fe$^{3+}$ ion, there is no any phase transition at the temperature range (from -160 $^{\circ}C$ to 20 $^{\circ}C$).

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1291-1296
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• 2006

This study was performed to determine the antimutagenic and anticancer effects of Fagopyrum esculentum Moenech noodles (FEMN) extracts using Ames test and cytotoxicity, respectively. FEMN made buckwheat wet noodles (BWN), buckwheat extruded noodles (BEN) and buckwheat dehydrated noodles (BDN) by 60% buckwheat flour and 70% buckwheat flour. The inhibitory effects of FEMN extracts on cell proliferation in A549, Hep3B, MCF-7, AGS and HeLa were investigated by SRB assay. The cytotoxic effects of FEMN against the cell lines with human lung carcinoma (A549), human gastric carcinoma (AGS), human hepatocellular carcinoma (Hep3B), human cervical adenocarcinoma (HeLa) and human breast adenocarcinoma (MCF-7) were inhibited with the increase of the extract concentration. The treatment of 1.0 mg/mL FEMN of 60% BEN extracts showed strong cytotoxicities of 74.7%, 75.3% and 70.5% against AGS, A549 and HeLa, respectively. The inhibition rate of 70% BWN of FEMN extracts in the S. Typhimurium TA100 strain showed 41% against the mutagenesis induced by MNNG. The inhibition rate of 70% BEN of FEMN extracts in the S. Typhimurium TA98 strain showed 45% against the mutagenesis induced by 4NQO.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.9
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• pp.714-719
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• 2001

SrBi$_2$Ta$_2$$O_{9}$ thn films were etched in inductively coupled Cl$_2$/CF$_4$/Ar plasma. THe maximum etch rate was 1060 $\AA$/min at a Cl$_2$/(Cl$_2$+CF$_4$+Ar)=0.2. The 20% additive Cl$_2$ into CF$_4$/Ar plasma decreased carbon and fluorine radicals, but increased Cl radicals. Sr was effectively removed by reacting with Cl radical because the boiling point of SrCl$_2$(125$0^{\circ}C$) is lower than that of SrF$_2$(246$0^{\circ}C$). The chemical reactions on the etched surface were studied with x-ray photoelectron spectroscopy and secondary ion mass spectrometry. The etching profile was evaluated by using scanning electron microscopy.y.

• Journal of Life Science
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• v.11 no.5
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• pp.432-438
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• 2001

Various lactic acid bacteria were isolated from Korean Dongchimi (whole radish Kimichi with added water) in order to study their antimutagenic activity. Ames test using Salmonella enterica serovar typhimurium TA98 and TA100 showed the strain DLAB19 to have the highest antimutagenic activity among the 300 isolated strains against MNNG(N-methyl-N-nitro-N-nitrosoguanidine), NPD (4-nitro-O-phenylenediamine), 4-NQO(4-nitroquinoline-1-oxide) and AFB$_{1}$(aflatoxin B$_{1}$). The strain was identified as Leuconostoc mesenteroides subsp. cremoris according to the Bergeys Mannual Systematic Bscteriology based on its morphological, cultural, physiological characteristics and biological system Antimutagenic activity of Leu. mesenteroides subsp. cremoris DLAB19 was found in the culture supernatant suggesting the bacterium secretes, the antimutagenic substance in the media. The antimutagenic activity of Leu. mesenteroides subsp. cremoris DLAB19 was reconfirmed by the spore-rec assay using spores of Bacillus subtilis H17 (Rec$^{+}$) and M45 (Rec$^{[-10]}$ ).).

• Journal of the Korean Magnetics Society
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• v.9 no.2
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• pp.98-103
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• 1999

We have studied changes of coercivity $(H_c)$, exchange anisotropy field $(H_{ex})$ and MR ration in glass/Ta/NiFeI/CoI(t)/Cu/CoII(3/4 t)/NiFeII/FeMn spin valve structures by changing Ar pressure and thicknesses of Co layers using DC, RF sputtering methods. We obtained minimum coercivity of 2.8 Oe at 4 mTorr of Ar pressure, exchange anisotropy field of 50.0 Oe at 6 mTorr and 5.3 % of MR ratio at 10 mTorr. Also, we obtained 3.0 Oe of coercivity at 40 $\AA$ of CoI layer, 65.9 Oe at 13 $\AA$ and 4.7 % of MR ratio at 27 $\AA$ and 34 $\AA$ by changing the thicknesses of Co layers.

• Journal of the Korean Ceramic Society
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• v.47 no.5
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• pp.461-466
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• 2010

In this study, $Al_2O_3/TaAlO_4/SiO_2$ (A/TAlO/S) structures with tantalum aluminate charge trap layer were fabricated for Nand flash memory device. We evaluated the memory window and retention characteristic as the thickness of the tunnel oxide was varied among 3 nm, 4 nm, and 5 nm. All tunnel oxide thicknesses were measured by ellipsometer and TEM (Transmission Electron Microscope). The A/TAlO/S multi-layer film consisted of 5 nm tunnel oxide showed the best result of memory window of 1.57 V and retention characteristics. After annealing the 5 nm tunnel oxide A/TAlO/S multi-layer film at $900^{\circ}C$. The memory window decreased to 1.32 V. Moreover, the TEM images confirmed that the thickness of multi-layer structure decreased 14.3% after annealing and the program conditions of A/TAlO/S multi-layer film decreased from 13 V to 11 V for 100 ms. Retention properties of both as-deposited and annealed films stably maintained until to $10^4$ cycles.

• Food Science and Preservation
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• v.15 no.4
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• pp.598-605
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• 2008

Korean traditional soy paste(Doenjang) was fermented for 90 days using, as a starter, a Meju prepared by inoculation of Bacillus subtilis cells. Changes in physiochemical and functional properties were investigated during fermentation. Amylase and protease activities increased and showed maximal levels(4.11 and 7.75 units/mL, respectively) after 60 days of fermentation. Both enzyme activities then fell. Inhibitory activities of the soy paste against tyrosinase and angiotensin converting enzyme(ACE) increased during the fermentation period. Antimutagenic activities during fermentation were determined using the S. enterica serovar Typhimurium TA100 and TA98 analysis system. No significant differences in activity were observed in soy pastes prepared with or without B. subtilis. Antimutagenic activities against the activities of N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) and 4-nitro-O-phenylenediamine (NPD) increased and reached 70.33% and 60.22%, respectively, after 90 days of fermentation, as assessed using the tester strain TA100. Against the actions of NPD and 4-nitroquinoline-1-oxide(NQO), antimutagenic activities also increased during fermentation and reached 50.84% and 47.01%, respectively, as assessed using the tester strain TA98. The genistin content was much higher(187.48 g/g) in soy paste prepared using B. subtilis inoculation than the level(31.30 g/g) seen in soy paste prepared without bacterial inoculation, although the contents of daidzein and genistein were slightly reduced under such circumstances.

• Proceedings of the Korean Ceranic Society Conference
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• 2000.04a
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• pp.32.1-32.1
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• 2000

• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.97.2-97
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• 2003

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.4
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• pp.416-421
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• 2008

This study was performed to determine the antimutagenic and anticytotoxic effects of soybean paste (doenjang) added deep sea water salt and see tangle in Salmonella Typhimurium TA98, TA100 and human cancer cell lines. In the Ames test, methanol extract of doenjang did not exhibit any mutagenicity but showed substantial inhibitory effects against mutation induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and 4-nitroquinoline-1-oxide (4NQO). The methanol extracts of doenjang ($200{\mu}g$/plate) added deep sea salt and see tangle (doenjang C) showed approximately 89.1% and 70% inhibitory effect on the mutagenesis induced by MNNG and 4NQO against TA100 strain, whereas 84.4% inhibitions were observed on the mutagenesis induced by 4NQO against TA98 strain. The cytotoxic effects of doenjang methanol extracts against the cell lines with human cervical adenocarcinoma (HeLa), human hepatocellular carcinoma (Hep3B), human gastric carcinoma (AGS), human lung carcinoma (A549) and human breast adenocarcinoma (MCF-7) were inhibited with the increase of the extract concentration. The treatment of 1.0 mg/mL doenjang C of methanol extracts showed strong cytotoxicities of 71%, 74.4%, 66.2%, 77.3%, and 71.2% against HeLa, Hep3B, AGS, A549, and MCF-7, respectively. In contrast 1 mg/mL treatment of doenjang C methanol extracts had only $10{\sim}40%$ cytotoxicity on normal human embryonal kidney cell (293). Doenjang methanol extract inhibited significantly the tumor growth in mice injected sarcoma-180 cells. Especially, doenjang C methanol extract showed an inhibition of tumor cell activity of 33% by the administration of 25 mg/kg methanol extracts.