• Journal of the Korean Magnetics Society
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• v.4 no.2
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• pp.122-125
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• 1994

The magnetic properties of Nd-Fe-B alloys of containing 4 at.% Nd have been studied for the development of new type rare-earth magnets. The amorphous phase of a melt-spun $Nd_{4}Fe_{85.5}B_{10.5}$ alloy is transformed into the phases which have a small amount of $Nd_{2}Fe_{14}B_{1}$ in ${\alpha}-Fe$ matrix by annealing above their crystallization temperature. The addition of Mo, Nb, V or Cu to $Nd_{4}Fe_{85.5}B_{10.5}$ alloy results in the reduction of grain size and the sub¬sequent improvement of the coercivity. The coercivity of $Nd_{4}Fe_{82}B_{10}M_{3}Cu_{1}$(M = Mo, Nb, V) alloys increases in the order of M = V < Nb < Mo and shows the highest value of 2.7 kOe when M = Mo. On the other hand, the rem¬anence of these alloys shows the opposite trend and the rn>st improved value of 1.35 T is observed when M = V.

• 한국균학회소식:학술대회논문집
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• 2015.11a
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• pp.23-23
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• 2015

Rice blast disease caused by M. oryzae is the most devastating fungal disease in rice. During the infection process, M. oryzae secretes a large number of glycosyl hydrolase (GH) proteins into the apoplast to digest host cell wall and assist fungal ingress into host tissues. In this study, we identified a novel M. oryze arabinofuranosidase B (MoAbfB) which is secreted during fungal infection. Live-cell imaging exhibited that fluorescent labeled MoAbfB was highly accumulated in fungal invasive structures such as appressorium, tips of penetration peg, biotrophic interfacial complex (BIC), as well as invasive hyphal tip. Deletion of MoAbfB mutants extended biotrophic phase followed by enhanced disease severity, whereas, over-expression of OsMoAbfB mutant induced rapid defense responses and enhanced rice resistance to M. oryzae infection. Furthermore, exogenous treatment of MoAbfB protein showed inhibition of fungal infection via priming of defense gene expression. We later found that the extract of MoAbfB degraded rice cell wall fragments could also induce host defense activation, suggesting that not MoAbfB itself but oligosaccharides (OGs) derived from MoAbfB dissolved rice cell wall elicited rice innate immunity.

• Journal of the Korean Chemical Society
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• v.37 no.7
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• pp.655-661
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• 1993

The neutral monomeric compounds $[Mo(NO)_2Cl_2(phen)]$ and $[W(NO)_2Cl_2(phen)]$ (phen= 1,10-phenanthroline) have been prepared by reactions of polymeric compounds $[{Mo(NO)_2Cl_2}n],\;[{W(NO)_2Cl_2}n]$ with chelate ligands. Additions of one equivalent of silver(I) perchlorate to these cis-dinitrosyl compounds in acetone solution produce $[Mo(NO)_2(phen)(S)Cl][ClO_4]\;and\;[W(NO)_2(phen)(S)Cl][ClO_4]$ (S = acetone). The homo- and hetero-dinuclear complexes, $[Cl(phen)(NO)_2M(pyz)M'(NO)_2(phen)Cl][ClO_4]_2$ (M = Mo, W) and $[Cl(phen)(NO)_2M(pyz)M'(NO)_2(phen)Cl][C1O_4]_2$ (M = Mo, M' = W) have been prepared by these monocationic complexes with pyrazine ligand respectively. These complexes characterized by elemental analysis, $1^H-\;and\;^{13}C-NMR$, infrared, and UV-visible spectroscopy are reported. The spectral data indicate that homo- and hetero-dinuclear complexes were symmetrical structures of $C_{2v}$.

• Analytical Science and Technology
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• v.6 no.3
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• pp.329-334
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• 1993

The formation of Mo(VI)-alizarin red S chelate ion its extraction into an organic solvent by ion-pairing for the separarive determination of trace Mo(VI) in natural water was applied in seawater samples. Removed Fe(III) and Zn(II), and Cu(II) by precipitating with anthranilic acid at pH 4.0 and 2.0, seawater 100mL was sampled in 250mL separatory funnel. After Mo(VI)-ARS chelate ion was formed by adding 0.01M alizarin red S solution 1.0mL to the water sample of pH 4.6, 0.6% aliquat-336 chloroform solution 10mL was added and the solution was vigorously shaked for about 30 seconds to form the ion-pair between Mo(VI)-ARS and aliquat-336 perfectly. The solution was stood for about 30 minutes. And the organic phase was taken for the absorbance measurement of the ion-pair at 520nm. The content of Mo(VI) was obtained from the standard calibration curve. Several extraction conditions such as pH, adding amounts of alizarin red S and aliquat-336, and shaking and standing times were optimized and the interferences and release of concomitant ions was also studied. This procedure was applied to the analysis of Eastern and Yellow seawaters. It could be confirmed from the recoveries of over 85% in samples spiked with a given amount of Mo(VI) that this method was also quantitative in the determination of trace Mo(VI) in a seawater.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.05a
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• pp.1393-1396
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• 2004

모바일 환경에서 멀티캐스트를 구현하는 방법으로 대표적인 방법으로는 원격가입(MIP-RS)와 양방향 터널링(MIP-BT)이 있으며 이의 단점을 보완한 MoM이 제안되었다. 하지만 터널링 경로가 최적으로부터 멀어지는 현상을 처리하지 못함에 따라 이를 해결하기 위해 터널링 범위에 제한을 가하는 RB MoM이 제안되었다. RB MoM의 경우 터널링 경로의 조절은 가능할 수 있었으나 이동호스트의 이동에 따른 HA 등록 등과 같은 등록메시지의 양은 줄일수는 없었다. 따라서 본 논문에서는 RB MoM의 장점인 터널링 경로 조절기능을 살리면서 이동호스트의 이동에 따른 등록메시지를 줄이고 GFA의 터널링 부하를 분산시키기 위해 멀티캐스트 터널링 범위에 제한을 둔 지역등록 기법을 제안하였다.

• Journal of Mechanical Science and Technology
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• v.16 no.11
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• pp.1420-1427
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• 2002

The Monkman-Grant (M-G) and its modified parameters were evaluated for type 316LN and modified 9Cr-Mo stainless steels prepared with minor element variations. Several sets of creep data for the two alloy systems were obtained by constant-load creep tests in 550～650$\^{C}$ temperature range. The M-G parameters, m, m', C, and C' were proposed and discussed for the two alloy systems. The m value of the M-C relation was 0.90 in type 316LN steel and 0.84 in modified 9Cr-Mo steel. The m' value of the modified relation was 0.94 in type 316LN steel and 0.89 in 9Cr-Mo steel. Although creep fracture modes and creep properties between type 316LN and modified 9Cr-Mo steels showed a basic difference, the M-G and its modified relations demonstrated linearity quite well. The m' of modified relation almost overlapped regardless of the creep testing conditions and chemical variations in the two alloy systems, and the parameter m' was closer to unity than that of the M-G relation.

• Journal of the Korean Chemical Society
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• v.29 no.5
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• pp.510-515
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• 1985

Color of $MoO_{(aq)}^{3+}$ in concentrated methanesulfonic acid (∼10M) changes dark green due to the formation of $Mo_2O_2(OH)_{2(aq)}^{4+}$ dimer. This color is similar to that shown by addition of water to that shown by addition of water to green $MoO_{(aq)}^{3+}$ solution in 15-16M methanesulfonic acid. The molar extinction coefficient of monomer in 15M methanesulfonic acid is about 20 at 415nm. Rate constants are independent on the aquomolybdenum (V) and hydrogen ion concentration under the condition of this experment. Bridging hydroxides of $Mo_2O_2(OH)_{2(aq)}^{4+}$ are dehydrogenated at the less concentration of ∼6 M for HPTS and ∼10M for $CH_3SO_3H$. The structure of both the yl-oxygens and the bridging oxygens of final product is identified to (*image)unit.

• Journal of the Korean Magnetics Society
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• v.1 no.2
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• pp.37-41
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• 1991

Amorphous $Fe_{68.5}Co_5M_3Cu_1Si_{13.5}B_9(M=Nb, Mo, Mn, Cr)$ alloys were prepared by using rapidly quenching techinque and were annealed above their crystallization temperatures. Coercive force, initial permeability and AC power loss of the annealed $Fe_{68.5}Co_5M_3Cu_1Si_{13.5}B_9(M=Nb, Mo, Mn, Cr)$ alloys have been studied systematically. Nanocrystallines are formed in the annealed alloys which include Mo and Nb. Remarkably improved soft magnetic properties are obtained in the alloys whose average grain size is around 10 nm. However, soft magnetic properties of the alloys are degraded when grain size is less than IOnm or larger than 15nm. It is considered that the degradation of soft magnetic properties in the alloys whose average grain size is less than 10 nm is due to the Fe-rich amorphous phase retained at grain boundary during the initial crystallization process.

• Elastomers and Composites
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• v.40 no.3
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• pp.174-180
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• 2005

Sonochemical synthesis of fullerene oxides $[C_{70}O_n](n=1{\sim}2)$ by fullerene$[C_{70}]$ and metal hexacarbonyl complexes $M(CO)_6$(M=Cr, Mo, W) took place under air atmosphere. The reactivity of fullerene$[C_{70}]$ and several metal hexacarbonyl complexes $M(CO)_6$(M=Cr, Mo, W) under same ultrasonic condition increased in the order of $Mo(CO)_6$ > $W(CO)_6$ > $Cr(CO)_6$. The MALDI-TOF-MS, UV-visible spectra, and HPLC analysis confirmed that the products of sonochemical reaction were $[C_{70}O_n](n=1{\sim}2)$.

• Analytical Science and Technology
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• v.6 no.3
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• pp.289-296
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• 1993

The formation of Mo(VI)-alizarin red S chelate ion and its extraction into an organic solvent by ion-pairing were studied for the separative determination of trace Mo(VI) in natural water samples. Natural water 100mL was sampled in 250mL separatory funnel. After Mo(VI)-ARS chelate ion was formed by adding 0.01M alizarin red S solution 0.5mL to the water sample of pH 4.0, 0.2% aliquat-336 chloroform solution 10mL was added and the solution was vigorously shaked for about 30 seconds to from the ion-pair between Mo(VI)-ARS and aliquat-336, completely. The solution was stood for about 90 minutes. And the organic phase was taken for the absorbance measurement of the ion-pair at 520 nm. The content of Mo(VI) in sample was obtained from the standard calibration curve. Several extraction conditions such as pH, adding amounts of alizarin red S and aliquat-336, and shaking and standing times were optimized. This procedure was applied to the analysis of river and tap waters. It could be confirmed from the recoveries of over 99% in samples spiked with a given amount of Mo(VI) that this method was quantitiative in the determination of trace Mo(VI) in a natural water.