• Bulletin of the Korean Chemical Society
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• 제33권5호
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• pp.1581-1585
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• 2012

Two pyridinecarboxamide dicyanidecobalt(III) building blocks and two mononuclear seven-coordinated macrocycle manganese(II) compounds have been rationally selected to assemble cyanide-bridged heterobimetallic complexes, resulting in three cyanide-bridged $Co^{III}-Mn^{II}$ complexes. Single X-ray diffraction analysis show that these complexes $\{[Mn(L^1)][Co(bpb)]\}ClO_4{\cdot}CH_3OH{\cdot}0.5H_2O$ ($\mathbf{1}$), $\{[Mn(L^2)][Co(bpb)]\}ClO_4{\cdot}0.5CH_3OH$ ($\mathbf{2}$) and ${[Mn(L^1)][Co(bpb)]\}ClO_4{\cdot}H_2O$ ($\mathbf{3}$) ($L^1$ = 3,6-diazaoctane-1,8-diamine, $L^2$ = 3,6-dioxaoctano-1,8-diamine; $bpb2^{2-}$ = 1,2-bis(pyridine-2-carboxamido)benzenate, $bpmb2^{2-}$ = 1,2-bis(pyridine-2-carboxamido)-4-methyl-benzenate) all present predictable one-dimensional single chain structures. The molecular structures of these one-dimensional complexes consists of alternating units of $[Mn(L)]^{2+}$ ($L=L^1$ or $L^2$) and $[Co(L^{\prime})(CN)2]^-$ ($L^{\prime}=bpb2^{2-}$, or $bpmb2^{2-}$), forming a cyanide-bridged cationic polymeric chain with free $ClO_4{^-}$ as the balance anion. The coordination geometry of manganese(II) ion in the three one-dimensional complexes is a slightly distorted pentagonal-bipyrimidal with two cyanide nitrogen atoms at the trans positions and $N_5$ or $N_3O_2$ coordinating mode at the equatorial plane from ligand $L^1$ or $L^2$. Investigation over magnetic properties of these complexes reveals that the very weak magnetic coupling between neighboring Mn(II) ions connected by the diamagnetic dicyanidecobalt(III) building block. A best-fit to the magnetic susceptibility of complex ${\mathbf}{1}$ leads to the magnetic coupling constants $J=-0.084(3)cm^{-1}$.

• Bulletin of the Korean Chemical Society
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• 제34권10호
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• pp.2947-2952
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• 2013

Three coordination polymers, [$ML_2(H_2O)_2$] (M = Co (1), Ni (2), Mn (3)), were prepared from metal acetates ($M(CH_3COO)_2{\cdot}4H_2O$) and 3-pyridinepropionic acid ($HL=(3-py)-CH_2CH_2COOH$) by solvent-layer methods. By contrast, a discrete molecular compound, trans-[$Pd(HL)_2Cl_2$] (4), was synthesized by replacing benzonitrile (PhCN) ligands in trans-[$Pd(PhCN)_2Cl_2$] with HL under microwave-heating conditions. Compounds 1-3 have a 2D framework, and compound 4 contains a square-planar Pd metal.

• 한국자기공명학회논문지
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• 제14권2호
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• pp.76-87
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• 2010

The structural phase transition of $Cs_2MnCl_4{\cdot}2H_2O$ single crystals was investigated by determining the $^{133}Cs$ spin-lattice relaxation time $T_1$. The number of resonance lines in the $^{133}Cs$ spectrum changes from seven to one near 375 K, which means that above 375 K the Cs sites are symmetric. Further, the $T_1$ of the $^{133}Cs$ nucleus undergoes a significant change near 375 K, which coincides with the change in the splitting of the $^{133}Cs$ resonance lines. The change in $T_1$ near $T_C$ is related to the loss of $H_2O$, and means that the forms of the octahedra of water molecules surrounding $Cs^+$ are disrupted.

• Journal of Microbiology and Biotechnology
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• 제32권2호
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• pp.248-255
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• 2022

Phlebia sp. MG-60 is the salt-tolerant, white-rot fungus which was isolated from a mangrove forest. This fungus expresses three kinds of manganese peroxidase (MGMnP) isozymes, MGMnP1, MGMnP2 and MGMnP3 in low nitrogen medium (LNM) or LNM containing NaCl. To date, there have been no reports on the biochemical salt-tolerance of these MnP isozymes due to the difficulty of purification. In present study, we established forced expression transformants of these three types of MnP isozymes. In addition, the fact that this fungus hardly produces native MnP in a high-nitrogen medium (HNM) was used to perform isozyme-selective expression and simple purification in HNM. The resulting MGMnPs showed high tolerance for NaCl compared with the MnP of Phanerochaete chrysosporium. It was worth noting that high concentration of NaCl (over 200 mM to 1200 mM) can enhance the activity of MGMnP1. Additionally, MGMnP1 showed relatively high thermo tolerance compared with other isozymes. MGMnPs may have evolved to adapt to chloride-rich environments, mangrove forest.

• 한국식품영양학회지
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• 제13권4호
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• pp.383-389
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• 2000

한국산 자초 적색소의 안정성을 연구한 결과 적색소의 온도에 대한 영향은 40~8$0^{\circ}C$의 조건에서 1~2 시간 정도의 가열로는 색상의 변화는 거의 없으나 장시간 보관시 55$^{\circ}C$ 이상 에서는 시간의 경과에 따라 색상이 현저하게 변화하였다. 적색소의 햇빛에 대한 영향은 적색 및 녹색 포장에서는 색상이 안정 하였으나 황색 및 청색 포장에서는 심한 색상의 변화를 보였다. 적색소의 pH에 대한 영향은 pH 4~8의 조건에서 색상이 매우 안정하게 나타났으며 pH 10 이상에서는 색상의 변화가 심하게 나타났다. 적색소의 금속이온에 대한 영향은 KCl, NaCl 첨가에서는 색상이 거의 변화하지 않았으나 CaCl$_2$, FeCl$_3$, CoCl$_2$, AlCl$_3$, MnCl$_2$ 첨가시에는 완전히 다른 색상으로 변화하였다. 적색소의 구연산, 초산에 대한 색소 안정성은 양호한 편이며 특히 초산에서는 색상의 변화가 없었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.343-346
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• 2001

To implementation of white electroluminescnet device in this paper, two methods were tried without synthesis of new white EL phosphor. At first, ZnS:Mn,Cl was mixed with ZnS:Cu from 20 to 50 weight percents. Second, ZnS:Mn,Cl was mixed with blue dye from 0 to 1.2 weight percents. The devices for experiments were measured as following; current-voltage, emission spectrum, brightness-voltage and CIE coordinate system and frequency properties.

• 한국수소및신에너지학회논문집
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• 제7권1호
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• pp.19-28
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• 1996

Ti-Mn based hydrogen storage alloy were modified by substituting alloying elements such as Zr, V and Ni in order to design a high capacity MH electrode for Ni/MH rechargeable battery. When V was substituted in Ti-Mn binary system, the crystal structure was maintained as $Cl_4$ Laves phase at a composition of $Ti_{0.2}V_{0.4}Mn_{0.4}$ and $Ti_{0.4}V_{0.2}Mn_{0.4}$ and equilibrium pressure decreased below 1 atm without decreasing hydrogen storage capacity considerably. It was found that Ni should be included in Ti-V-Mn alloy in order to hydrogenate it electrochemically in KOH electrolyte. But substitution of Ni for Mn in Ti-V-Mn system caused the increase of equilibrium pressure above 1atm and decrease of hydrogen storage capacity. Zr was able to increase the reversible hydrogen storage capacity of Ti-V-Mn-Ni alloy without considerable change of hydrogenation properties. The electrochemical discharge capacity of Ti-Zr-V-Mn-Ni system were in the range of 350 - 464mAh/g and among them $Ti_{0.8}Zr_{0.2}V_{0.5}Mn_{0.5}Ni_{1.0}$ alloy had $Cl_4$ Laves single phase and very high electrochemical discharge capacity of 464mAh/g.

• 한국결정성장학회지
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• 제6권4호
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• pp.600-608
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• 1996

리튬 이온이 intercalation되어 스핀넬 구조를 이루고 있는 $Li_{x}Mn_{2}O_{4}(0.2{\leq}x{\leq}2.0)$의 구조적 특성을 X-선 회절분석과 Li/1M $LiClO_{4}$-propylene carbonate solution/$Li_{x}Mn_{2}O_{4}$ 전지에서 이들의 구조적 특징에 의한 전기화학적 특성을 연구하였다. $Li_{x}Mn_{2}O_{4}$의 전기화학적 특성에 대한 조성과 반응온도의 영향은 상전이 현상과, 결정 상수 측정과 열분석에 의하여 연구하였다. 산처리 후 $Li_{x}Mn_{2}O_{4}$는 거의 순수한 ${\lambda}-MnO_{2}$구조로 상전이 되었으며 이때 격자상수 $a_{c}$가 8.255에서 $8.031\;{\AA}$으로 수축되었다. $Li_{x}Mn_{2}O_{4}$의 조성 범위가 $0.2{\leq}x{\leq}0.6$일 때 격자상수 $8.255\;{\AA}$의 단일상을 나타내며 3.9~3.7 V의 전위 평탄 영역을 나타낸다.

• 대한간호학회지
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• 제28권4호
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• pp.869-880
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• 1998

In order to investigate of the effects of rapid rotating shift work on physiological stress, the activities of urinary Na$^{+}$, $K^{+}$, Cl$^{[-10]}$ were measured in 14 rotational shift nurses, during day shifts(8AM-4PM, n=4), evening shifts(4PM-l2MN, n=5), and night shifts(12MN-8AM, n=5) in hospital twenty students attending nursing college a used as a control group. Urine specimens were collected in 30 minutes before and after work on the second day of shift work. In day shift nurses, Na$^{+}$ activity was 137mM at 8AM and increased to 206mM at 4PM, whereas $K^{+}$ activity was 42mM at 8AM and no significant change at 4PM. Cl$^{[-10]}$ activity was changed from 234mM to 344mM at 4PM at 8AM. In the evening shift, Na$^{+}$ activity was 117mM at 4PM and 140mM at 12MN, $K^{+}$ activity was 22mM and 32mM, respectively. Cl$^{[-10]}$ activity was 169mM and changed to 270mM. During the night shift, Na$^{+}$ activity was 128mM at 12MN and changed to 161mM at 8AM, $K^{+}$ activity was 42mM at 12MN and 8AM, and Cl$^{[-10]}$ activity was from 303mM and changed to 355mM. In general, the urinary ion activities seemed to increase after work, however there were no significant changes in ion activities except the Na$^{+}$ increase in day shift. The mean of the activities of $K^{+}$ and Cl$^{[-10]}$ before and after work during the day and night shift were significantly higher than those in control group (P＜0.05). $K^{+}$ activities were also higher than that of evening shift(P＜0.05). However, there was no difference in Na$^{+}$ activity among the control group and three shifts. There was a significant relationship among urinary Na$^{+}$, Cl$^{[-10]}$ and $K^{+}$ in the control group and rotating shift nurses except between Na$^{+}$ and $K^{+}$ in shift. The relationship between Na$^{+}$ and Cl$^{[-10]}$ was low in shift work and there was no significant relationship between Na$^{+}$ and $K^{+}$ in shift, suggesting that the active regulation $K^{+}$ and/or Na$^{+}$ in response to stress upon the shift work disruped the ratio of urinary Na$^{+}$ to $K^{+}$ and also lowered the relationship between $K^{+}$ and Cl$^{[-10]}$ . These results suggest that nurses working the day shift were overloaded and under stress, and the night shift interfered with the physiological rhythm of the nurses.red with the physiological rhythm of the nurses.

• 한국세라믹학회지
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• 제36권1호
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• pp.82-88
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• 1999

본 연구에서는 fine ceramics의 합성법을 traditional ceramics 합성에 적용하여 합성한 내화재료용 mullite에 광화제를 첨가함으로서 광화제가 mullite 생성에 미치는 영향을 관찰하고자 한다. 출발물질로 하동 kaolin과 boehmite를 사용하였으며, 여기에 광화제로 MnO와 TiO2를 액상으로 첨가하였다. 그 결과 3.5 wt% MnO를 첨가한 경우, 1,25$0^{\circ}C$에서 미반응 silica와 alumina가 존재하지 않는 단일상의 mullite를 합성할 수 있었으며, TiO2 첨가시 2~3.5wt% MnO의 경우 mullite 생성 온도를 약 10$0^{\circ}C$ 낮출 수 있었다. 이때의 mullite 생성율은 1$650^{\circ}C$에서 84%이며, 부피 비중과 흡수율 및 상온에서 꺾임강도는 각각 2.72, 0.27%, 180MPa을 나타내어 광화제를 첨가하지 않은 경우보다 특성도 향상함을 알 수 있었다.