• 대한화학회지
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• 제39권7호
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• pp.552-558
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• 1995

배위자인 이소부틸, 노르말 부틸 및 메틸티오아세트아미드옥심과 출발 물질인 단핵 및 다핵 착물과의 반응에서 $X_2[M_{O4}O_12{R'C(NH_2)NO}_2](X=n-Bu_4N^+$, $R'=(CH_3)_2CH$, $CH_3CH_2CH_2$, $CH_3SCH_2$; $X=(CH_3)_2CHC(=NH_2)NH_2^+$, $R'=(CH_3)_2CH$; $X=CH_3CH_2CH_2C(=NH_2)NH_2^+$, $R'=CH_3_CH_2CH_2$; $X=CH_3SCH_2C(=NH_2)NH_2^+$, $R'=CH_3SCH_2)$을 합성하였다. 합성한 착물은 원소분석, 적외선 및 핵자기공명에 의해 구조를 규명하였다. 얻은 착물중 ${(CH_3)_2CHC(NH_2)_2}_2[M_{O4}O_{12}{(CH_3)_2CHC(NH_2)NO}_2]$은 X-선 단결정 회절에서 결정구조를 밝혔고, 얻은 데이타는 Monoclinic, $P2_{1/c}$, $a=10.168(3){\AA}$, $b=11.768(1){\AA}$, $c=13.557(1){\AA}$, ${\beta}=102.08(1)^{\circ}$, $V=1586.2(5){\AA}^3$, Z = 2이었고, 회절강도 2951개($F_0>3s(F_0)$)에 대한 최종 신뢰도 인자는 0.026이었다. 이 착물의 구조는 평면상의 환형$[Mo_4({\mu}-O)_4]$과 두 개의 ${\mu}_4$-아미드옥시메이트로 구성되어 있다.

• Environmental Engineering Research
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• 제12권4호
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• pp.157-175
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• 2007

The membrane biofilm reactor (MBfR) creates a natural partnership of a membrane and biofilm, because a gas-transfer membrane delivers a gaseous substrate to the biofilm that grows on the membrane's outer wall. $O_2$-based MBfRs (called membrane aerated biofilm reactors, or MABRs) have existed for much longer than $H_2$-based MBfRs, but the $O_2$-based MBfR is a versatile platform for reducing oxidized contaminants in many water-treatment settings: drinking water, ground water, wastewater, and agricultural drainage. Extensive bench-scale experimentation has proven that the $H_2$-based MBfR can reduce many oxidized contaminant to harmless or easily removed forms: e.g., ${NO_3}^-$ to $N_2$, ${ClO_4}^-$ to $H_2O$ and $Cl^-$, ${SeO_4}^{2-}$ to $Se^0$, and trichloroethene (TCE) to ethene and $Cl^-$. The MBfR has been tested at the pilot scale for ${NO_3}^-$ and ${ClO_4}^-$ and is now entering field-testing for many of the oxidized contaminants alone or in mixtures. For the MBfR to attain its full promise, several issues must be addressed by bench and field research: understanding interactions with mixtures of oxidized contaminants, treating waters with a high TDS concentration, developing modules that can be used in situ to augment pre-denitrification of wastewater, and keeping the capital costs low.

• 한국결정학회지
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• 제12권4호
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• pp.212-215
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• 2001

NaOAC·3H₂O 존재 하에서, manganese nitrate(Mn(NO₃)₂·H₂O )와 imidzole-4,5-dicarboxylic acid(IDCH₂)가 수열반응하여, 실험식 [Mn(IDC)(H₂O)]을 가지는 2차원 배위고분자 합성되었다. 화합물 1의 구조가 분광학적 방법(IR) 및 X-ray 회절법으로 규명되었다. 화합물의 1의 결정학적 자료: 사방정계 공간군 Pbca, a=7.257(5) Å b=13.687(5)Å, c=14.332(6)Å Z=8, R(wR₂)=0.0498(0.0999).

• 한국결정학회지
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• 제12권3호
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• pp.145-149
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• 2001

Pyrazine 존재 하에서, Zn(NO₃)₂·존재 하에서 . Zn(NO,)7·6H₂O와 K₂HPO₄가 수열반응하여 Zn₃(PO₄)₂(H₂O) (1)실험식을 갖는 3차원 zinc-phosphate 배위 고분자가 합성되었다. 화합물 1의 구조가 IR 분광법 및 X-ray 회절법으로 규명되었다. 화합물 1의 결정학적 자자료: 단사정계 공간군 P2₁/c, a=8.750(1)Å, b=4.901(1)Å, c=16.759(3)Å, β=94.98(2)°, Z=4, R(wR₂)=0.0332(0.0927).

• 한국자기학회지
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• 제5권5호
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• pp.552-555
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• 1995

The magnetic properties of Mg-Mn ferrites were investigated in the composition range of $Mg_{a}Mn_{b}Fe_{c}O_{4\pm\delta}$ (a+b+c=3) with the addition of $Al_{2}O_{3}$. In $MgO-MnO-Fe_{2}O_{3}$ ternary system, the spinel single phase existed within the composition range of MgO-50 mol%, MnO-70 mol% and $Fe_{2}O_{3}-60\;mol%$. The saturation magnetic flux density increased with the increase of $Fe_{2}O_{3}$ content and showed the maximum at the stoichiometric composition of $(Mg,Mn)Fe_{2}O_{4}$. In $Mg_{x}Mn_{1-x}Fe_{2}O_{4}(x=0.2~0.8)$ system, the saturation magnetic flux density showed the maximum at $Mg_{0.2}Mn_{0.8}Fe_{2}O_{4}$. The addition of $Al_{2}O_{3}$ resulted in the decrease of saturation magnetic flux density but increased the electrical resistivity.

• Bulletin of the Korean Chemical Society
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• 제27권7호
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• pp.1038-1042
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• 2006

A new type of DTPA-bis-amides (L1-L4) and their Gd(III)-complexes of the type $[Gd(L)(H_2O)]{\cdot}nH_2O$ (5: L1; 6: L2; 7: L3; 8: L4) have been prepared and characterized by analytical and spectroscopic techniques. The X-ray crystal structure of 8 has been determined for structural confirmation. The coordination geometry adopts a tricapped trigonal prism geometry with L4 acting as a chelate octadentate and a water molecule in the coordination sphere. Crystals are monoclinic, $P2_1$, a = 14.468(3), b = 19.235(4), c = 13.527(2) $\AA$ $\beta$ = $107.245(3)^{\circ}$, V = 3595.2(11) $\AA^3$, Z = 4, $D_{calc}$ = 1.570. Significant increases in relaxivities are observed with 6 and 7 as compared with that of $Omniscan^{(R)}$, a commercial MR agent: R1 = 12.46 $mM^{-1}\;s^{-1}$, R2 = 8.76 $mM^{-1}\;s^{-1}$ for 6; R1 = 12.77 nm-1 s-1, R2 = 7.60 mM-1 s-1 for 7; R1 = 4.9 $mM^{-1}\;s^{-1}$, R2 = 4.8 $mm^{-1}\;s^{-1}$ for $Omniscan^{(R)}$. In the case of 5, however, both R1 and R2 are found to be lower to show 2.09 $mM^{-1}\;s^{-1}$, and 1.82 $mM^{-1}\;s^{-1}$, respectively.

• Bulletin of the Korean Chemical Society
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• 제15권1호
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• pp.37-45
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• 1994

$(NH_4)_{4.5}[H_{3.5}{\alpha}-PtMo_6O_{24}]{\cdot}1.5\;H_2O(A),\;(NH_4)_4[H_4{\beta}-PtMo_6O_{24}]{\cdot}1.5\;H_2O(B),\;and\;K_{3.5}[H_{4.5}{\alpha}-PtMo_6O_{24}]{\cdot}3\;H_2O(C)$ have been synthesized and their molecular structures have been also determined by single-crystal X-ray diffraction technique. The space groups, unit cell parameters, and R factors are as follows: Compound A, monoclinic, $A_{2/a}$, a= 19.074 (3), b=21.490 (3), c=15.183 (2) ${\AA};\;{\beta}$=109.67 (1) ${\AA}$; z=8; R=0.075($IF_0I>4{\sigma}(IF_0I);$ Compound B, triclinic, P$bar{1}$, a=10.776 (2), b=15.174 (4), c=10.697 (3) ${\AA};\;{\alpha}$ =126.29 (2), ${\beta}$=111.55 (2), ${\gamma}$=93.18 (2) ${\AA}$; Z=2; R=0.046($IF_0I>3{\sigma}(IF_0I);$): Compound C, triclinic, Pl, a=12.426 (2), b=13.884 (2), c=10.089 (1) ${\AA}$; ${\alpha}$=102.59 (2), ${\beta}$=110.73 (1), ${\gamma}$=53.93 (1) ${\AA}$; Z=2; R=0.074 ($IF_0I>3{\sigma}(IF_0I)$. Compounds A and C contain the well-known Anderson structure (planar structure) heteropoly oxometalate having approximate $bar{3}_m(D_{3d})$ symmetry, while compound B contains the bent structure heteropoly oxometalate having appproximate $2_{mm}(C2_v)$ symmetry. The bent structure and the planar one are geometrical isomers. These compounds are rot only novel heteroply molybdates containing platinate(IV) but also the first example of geometrical isomerism in the hexamolybdoheteropoly oxometalates. That isomerization surprisingly occurred because of the change of only 0.5 non-acidic hydrogen atom attached to the polyanion such as $[H_{3.5}{\alpha} -PtMo_6O_{24}]^{4.5-}{\to}[H_4{\beta}-PtMo_6O_{24}]^{4-}{\to}[H_{4.5}{\alpha} -PtMo_6O_{24}]^{3.5-}$. It seems that the gradual protonation of the polyanion plays an important role in that isomerism. These heteropolyanions form dimers by strong hydrogen bonds between two heteropolyanions in the respective crystal system.

• 한국전기전자재료학회논문지
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• 제29권10호
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• pp.652-658
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• 2016

Thermal batteries use inorganic salt as electrolyte, which is inactive at room temperature. As soon as heat pellets are fired by an igniter, all the solid electrolytes are instantly melted into excellent ionic conductors. However, the abnormal heat generation by the igniter flame or heat pellets causes the thermal decomposition of the electrode and the melting of the anode, eventually leading to a thermal runaway, which results in overheating or explosion. The thermal runaway can be significantly reduced by the adoption of $Zr/BaCrO_4$ heat papers. In this study, the heat papers with various ratios of fuel (Zr) and oxidizer ($BaCrO_4$) were prepared by the paper-making process. We have investigated the calorimetric value, burning rate, and ignition sensitivity. The ignition test of heat pellets and the discharge test of thermal batteries were also carried out. At the composition of 40 wt.% of Zr, the heat papers showed the highest specific calorimetric value and burning rate. As a result, $Zr/BaCrO_4$ heat paper made by the paper-making process has shown the applicability for thermal batteries.

• 미생물학회지
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• 제32권3호
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• pp.182-185
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• 1994

구름버섯에 의한 Poly R-478염료의 탈색에 미치는 탄소원과 질소원의 영향을 조사하였다. 2.0% glucose, 0.04% ammonium tartrate, 2% $KH_2PO_4$, 0.5% $MgSO_4{\cdot}7H_2O$, 0.1% $CaCl_2{\cdot}2H_2O$, 0.002% thiamine-HCI, 10 mM 2,2-dimethylsuccinate(sodium)와 0.02% Poly R-478 염료 등으로 조성된 질소제한배지에서 균주를 $28^{\circ}C$에서 10일간 정치배양 했을때 염료의 탈색율은 87.2%로 나타났다. 염료의 탈색은 배지내에 질소원이 존재할 때에 일어났으며 탈색율은 배지내에 질소원이 고갈된 직후에 급격히 증가하였다.

• 한국결정학회지
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• 제13권1호
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• pp.12-16
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• 2002

[Ni(L)](BDC)·4H₂O (1) (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[16,4,O/sup 1.18/,O/sup 7.12/]docosane;BDC = 1,3-benzenedicarboxylate) 착물을 합성하고 구조를 규명하였다. 이 착물은 사방정계, 공간군 Pcnb, a = 8.764(2) , b = 17.687(2) , c = 19.475(1) , V = 3018.7(8) ³, Z = 4로 결정화 되었다. 이 착물의 구조는 최소자승법으로 정밀화하였으며, 최종 신뢰도 R₁(wR₂)값은 2148개의 회절반점에 대하여 0.0822 및 0.2236이었다. 화합물 1은 수소결합들로 연결된 삼차원의 그물 구조를 갖는다.