• Title/Summary/Keyword: MgB$_{2}$

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Effect of B-9 and Uniconazole on the Growth of Mentha piperita, Origanum vulgare L., and Thymus vulgaris L. (몇몇 허브식물의 생육에 미치는 B-9과 Uniconazole 처리효과)

  • Lee, Jeong Hwa;Moon, Yuon Ja;Park, Ki Bae;Huh, Moo Ryong;Park, Joong Choon
    • Horticultural Science & Technology
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    • v.17 no.2
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    • pp.131-133
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    • 1999
  • The plant height and internodal length of Mentha piperita, Origanum vulgare L., and Thymus vulgaris L. were reduced according to the treatment of 500, 2,500, 5,000 mg/L B-9 and 0.5, 1.0, 5.0 mg/L uniconazole. On the efficiency of dwarfing in 3 herb species, uniconazole was more effective than B-9, but plant height of Thymus vulgaris was more shortened with 2,500mg/L B-9 treatment than 3 levels of uniconazole treatments. Cuttings from 3 kinds of herbs tested were died with 5,000mg/L B-9 treatment. The number of lateral shoots per plant was heighest at control plants and uniconazole was more effective in reducing lateral shoots than B-9. There was no significant difference in leaf growth between B-9. There was no significant difference in leaf growth between B-9 and uniconazole treatments. The root growth of Mentha poperita, Origanum vulare, and Thymus vulagris was not significantly affected by B-9 or uniconazole.

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The Crystallization of LiO2-MgO-MgF2-SiO2 Glass System by B2O3 addition (B2O3의 첨가에 따른 저온 소결기판용 LiO2-MgO-MgF2-SiO2계 유리의 결정화에 관 한 연구)

  • 김병일
    • Journal of the Microelectronics and Packaging Society
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    • v.5 no.1
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    • pp.31-38
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    • 1998
  • 저온소결기판용 Glass-ceramics를 제조하기 위해 LiO2-MgO-MgF2-SiO2계 조성에 서 B2O3첨가가 결정화 특성 및 물성에 미치는 영향을 고찰하였다. 145$0^{\circ}C$에서용융하여 제조 한 모유리의 핵형성 온도와 결정화 온도를 결정하기 위해 TMA와 DTA분석을 실시하였다. 결정화시킨 유리의 결정상과 미세구조를 관찰하기 위하여 XRD와 SEM관찰을 실시하였다. Water swelling을 통해 Glass-ceramics powder를 제조하였으며 제조한 powder의 평균입자 크기는 8.32$\mu$m였다.

The Crystallization of $Li_2O-MgO-MgF_2-SiO_2$ Glass System by $B_2O_3$ addition (B$_2$O$_3$의 첨가에 따른 저온 소결기판용 $Li_2O-MgO-MgF_2-SiO_2$)

  • 박대현;강원호
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1997.11a
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    • pp.39-43
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    • 1997
  • Effects of B$_2$O$_3$ addition in the Li$_2$O-MgO-MgF$_2$-SiO$_2$g1ass system were investigated in order to make glass-ceramics for low temperature firing substrate. Base glass was made by melting at 145$0^{\circ}C$ . This glass was analyzed by THA and DTA to settle nucleation and crystallization temperature. After crystallization. crystal phase and microstructure were absorvated by XRD and SEM. Glass powders were made by water swelling method. Average particle size was 5.44${\mu}{\textrm}{m}$

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Acute Oral Toxicity Study of Standardized Herbal Preparations(Gami-Samhwang-San, SH-21-B) in Rats (HPLC로 표준화한 가미삼황산(加味三黃散) 분획물(SH-21-B)의 랫드에 대한 단회경구투여독성시험)

  • Yu, Young-Beob;Kim, Seon-Hyeong;Yoon, Yoo-Sik
    • Toxicological Research
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    • v.21 no.3
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    • pp.255-261
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    • 2005
  • Gami-Samhwang-San, a herbal prescription for obesity treatment, is composed of seven crude herbs such as Rehmanniae Radix Preparata, Ephedrae Herba, Scutellariae Radix, Acori Gramineri Rhizoma, Polygalae Radix, Typhae Pollen, Armeniacae Semen, Menthae Herba. In this study, marker substances in n-butanol fraction (SH-21-B) from Gami-Samhwang-San were analyzed by high performance liquid chromatography (HPLC) and acute toxicity of standardized SH-21-B was evaluated by good laboratory practices (GLP) guideline of Korea Food and Drug Administration. Therefore we confirmed that there were baicalin of 15.92%, amygdalin of 6.57% and ephedrine of 2.49% in SH-21-B. SH-21-B was administered in rats at dose of 0 mg/kg, 2,000 mg/kg, and 5,000mg/kg. Clinical signs of both sexes of rats were observed daily for 14 days after single oral administration. Two female rats one administered at 2,000 mg/kg and the other administered at 5,000 mg/kg, died, but no dead animal was observed among male rats. Therefore $LD_{50}$ in the female rat is observed to be 8,710 mg/kg, and MLD (Minimun Lethal Dose) of the male rat is observed to be more than 5,000 mg/kg.

Superconducting Properties of Mg(B1-xCx)2 Bulk Synthesized Using Magnesium and Glycerin-treated Boron Powder (마그네슘과 글리세린 처리한 붕소 분말로 합성한 Mg(B1-xCx)2의 초전도 특성)

  • Kim, Yi-Jeong;Jun, Byung-Hyuk;Park, Soon-Dong;Tan, Kai Sin;Kim, Bong-Goo;Sohn, Jae-Min;Kim, Chan-Joong
    • Journal of Powder Materials
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    • v.15 no.3
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    • pp.182-187
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    • 2008
  • Carbon was known to be one of effective additives which can improve the flux pinning of $MgB_2$ at high magnetic fields. In this study, glycerin $(C_3H_8O_3)$ was selected as a chemical carbon source for the improvement of critical current density of $MgB_2$. In order to replace some of boron atoms by carbon atoms, the boron powder was heat-treated with liquid glycerin. The glycerin-treated boron powder was mixed with an appropriate amount of magnesium powder to $MgB_2$ composition and the powder pallets were heat treated at $650^{\circ}C\;and\;900^{\circ}C$ for 30 min in a flowing argon gas. It was found that the superconducting transition temperature $(T_c)$ of $Mg(B_{1-x}C_x)_2$ prepared using glycerin-treated boron powder was 36.6 K, which is slightly smaller than $T_c$(37.1 K) of undoped $MgB_2$. The critical current density $(J_c)$ of $Mg(B_{1-x}C_x)_2$ was higher than that of undoped $MgB_2$ and the $T_c$ improvement effect was more remarkable at higher magnetic fields. The $T_c$, decrease and $J_c$ increase associated with the glycerin treatment for boron powder was explained in terms of the carbon substitution to boron site.

Effects of Glucosamine Hydrochloride, Taurine and Their Combined Administration on Anti-inflammatory and Analgesic Action in Rats (흰쥐의 항염증 및 진통작용에 대한 Glucosamine Hydrochloride와 Taurine 및 그 혼합 투여시의 효과)

  • 김옥경
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.28 no.5
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    • pp.1113-1123
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    • 1999
  • The purpose of this study was to see the effect of anti inflammatory and analgesic action of the glucosamine hydrochloride(GA HCl) or taurine. Male Sprague Dawley rats(100~250g) and ICR mice(20 ~30g) were used. Experimental groups were divided into seven groups, one control group given as saline and six groups given as oral administration of GA HCl or taurine; GA HCl 250mg/kg, b.w group, taurine 250mg/kg, b.w group, GA HCl 250mg/kg, b.w+taurine 250mg/kg, b.w group, GA HCl 500mg/kg, b.w group, taurine 500mg/kg, b.w group, GA HCl 500mg/kg, b.w+taurine 500mg/kg, b.w group. Carrageenan induced edema test were shown to be significantly inhibited in the GA HCl 250mg/kg group and taurine 250mg/kg group compared to the control group, but the GA HCl 500mg/kg+taurine 500mg/kg group were significantly inhibited than the control group. Capillary permeability test were shown to be sig nificantly inhibited in the taurine 500mg/kg group, but the GA HCl 500mg/kg+taurine 500mg/kg group were significantly inhibited than the control group. Leucocyte emigration test were shown to be significantly inhibited in the GA HCl 250mg/kg+ taurine 250mg/kg group and GA HCl 500mg/kg+taurine 500mg/kg group compared to the control group. Acetic acid, Phenyl p benzoquinone writhing syndrome were shown to be significantly inhibited in the GA HCl 500mg/kg+taurine 500mg/kg group compared to the control group. Inhibitory action against COX 1 and COX 2 were not significantly inhibited in the experimental group. These results suggest that the combined administration of the GA HCl and taurine have potential action in anti inflammatory and analgesic action.

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Domination of glassy and fluctuation behavior over thermal activation in vortex state in $MgB_2$ thin film ($MgB_2$ 박막에서의 열적 활성화에 비해 두드러진 볼텍스 유리화 및 열적 요동현상의 연구)

  • Kim, Heon-Jung;W. N. Kang;Kim, Hyeong-Jin;Park, Eun-Mi;Kim, Kijoon H. P.
    • Progress in Superconductivity
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    • v.3 no.1
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    • pp.23-27
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    • 2001
  • We have investigated the mixed-state magnetoresistance of high quality c-axis-oriented MgB2 thin film for magnetic field from 0.5 T to 5.0 T, applied normal to ab-plane. The temperature dependence of magnetoresistance was well described by vortex glass and fluctuation theories for different temperature regimes. We observed glassy exponent of v(z-1)~3 and upper critical field of $H_{c2}$(0)~35 T, which is consistent with previous data obtained from direct $H_{c2}$(0) measurements. Interestingly, the thermally activated flux flow region was observed to be very narrow, suggesting that the pinning strength of this compound is very strong. This finding is closely related to the recent reports that the bulk pinning is dominant in $MgB_2$and the critical current density of $MgB_2$ thin film is very high, comparable to that of cuprate superconductor. The present results further suggest that $MgB_2$is beneficial to technical applications.ons.

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Culture Characteristics on the Activity of ${\gamma}-Glutamyltranspeptidase{\;}({\gamma}-GTP)$ by Bacillus subtilis Fusant (배양조건이 Bacillus subtilis 융합주의 ${\gamma}-Glutamyltranspeptidase{\;}({\gamma}-GTP)$ 활성에 미치는 영향)

  • 김관필;김성호;정낙현
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.3
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    • pp.395-402
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    • 2001
  • A fusant FG-21 was selected on the basis of higher ${\gamma}-GTP$ activity following fusion process between SM-2 and SM-10 of Bacillus subtilis mutants. ${\gamma}-GTP$ activity of the mutant FG-21 was increased up to 612 U/mL when grown for 36 hr at $37^{\circ}C$ in culture media containing 1% glycerol 1% glycerol, 1% peptone, 0.1% citric acid, 5 mM $K_2HPO_4$, 1 mM $FeCl_3$, 1 mM $MgCl_2$, 1 mM $NH_4Cl$, pH 7.0. In fusnat FG-21, the ratio of protein to total sugar contents for biopolymer A was 38 to 59. for biopolymer B from parental strains it was 19 to 78. Fructose contents determined by HPLC were $573.7\;\mu\textrm{g}/mg\;and\;764.4\;\mu\textrm{g}/mg$ for biopolymer A and B, respectively. And glutamic acid content were $163.7\;\mu\textrm{g}/mg\;and\;94.6\;\mu\textrm{g}/mg$ for biopolymer A and B, respectively. In fusant FG-21, the ratio of fructose to glutamic acid contents for biopolymer A was 78 to 22. For biopolymer B from parental strains it was 89 to 11.

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A Study on the Composition of Seasoning Using Lentinus edodes. (표고버섯을 이용한 조미료의 주요성분에 관한 연구)

  • 차월석;이명렬;조배식;박세영
    • Journal of Life Science
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    • v.14 no.5
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    • pp.829-833
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    • 2004
  • The major compositions of Lentinus edodes seasoning(LES) compose of 30.3% of Lentinus edodes fruit body, 18.1 % of anchovy (Engraulis japonicus) powder and 51.6% of sea tangle (Laminaria japonica), prawn and green tea powder and so on were investigated in order to evaluate the nutritional value. Sodium concentration in LES was high up to 5,042.99 mg/IOO g and K, Ca, P, Mg, Fe, Zn, Mn and Cu were followed. There were nineteen total amino acids in LES. The glutamic acid content was high up to 4.62 mg/100 mg and glycine, leucine, alanine, aspartic acid were followed. Among twenty free amino acids, glycine content was high up to 2.37 mg/100 mg and glutamic acid, asparanine, proline, taurin and aspartic acid were followed. The contents of vitamin C in LES was high up to 224.78 mg/100 g and pantothenic acid, vitamin B$_{6}$, niacin, vitamin E, folic acid, vitamin B$_{l}$ vitamin B$_{2}$, vitamin D$_{3}$, vitamin A, vitamin B$_{12}$ and vitamin $K_{l}$ were followed.wed.

Characteristics of a Novel Acinetobacter sp. and Its Kinetics in Hexavalent Chromium Bioreduction

  • M., Narayani;K., Vidya Shetty
    • Journal of Microbiology and Biotechnology
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    • v.22 no.5
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    • pp.690-698
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    • 2012
  • Cr-B2, a Gram-negative hexavalent chromium [Cr(VI)] reducing bacteria, was isolated from the aerator water of an activated sludge process in the wastewater treatment facility of a dye and pigment based chemical industry. Cr-B2 exhibited a resistance for 1,100 mg/l Cr(VI) and, similarly, resistance against other heavy metal ions such as $Ni^{2+}$ (800 mg/l), $Cu^{2+}$ (600 mg/l), $Pb^{2+}$ (1,100 mg/l), $Cd^{2+}$ (350 mg/l), $ZN^{2+}$ (700 mg/l), and $Fe^{3+}$ (1,000 mg/l), and against selected antibiotics. Cr-B2 was observed to efficiently reduce 200 mg/l Cr(VI) completely in both nutrient and LB media, and could convert Cr(VI) to Cr(III) aerobically. Cr(VI) reduction kinetics followed allosteric enzyme kinetics. The $K_m$ values were found to be 43.11 mg/l for nutrient media and 38.05 mg/l for LB media. $V_{max}$ values of 13.17 mg/l/h and 12.53 mg/l/h were obtained for nutrient media and LB media, respectively, and the cooperativity coefficients (n) were found to be 8.47 and 3.49, respectively, indicating positive cooperativity in both cases. SEM analysis showed the formation of wrinkles and depressions in the cells when exposed to 800 mg/l Cr(VI) concentration. The organism was seen to exhibit pleomorphic behavior. Cr-B2 was identified on the basis of morphological, biochemical, and partial 16S rRNA gene sequencing chracterizations and found to be Acinetobacter sp.