• Bulletin of the Korean Chemical Society
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• 제26권8호
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• pp.1185-1189
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• 2005

Two new copper vanadium borophosphate compounds, $(NH_4)(C_2H_{10}N_2)_{5.5}[Cu(C_2H_8N_2)_2]_3[V_2P_2BO_{12}]_6{\cdot}17H_2O,\;Cu-VBPO1\;and\;(NH_4)(C_2H_{10}N_2)_{3.5}[Cu(C_2H_8N_2)_2]_5[V_2P_2BO_{12}]_6{\cdot}18H_2O$, Cu-VBPO2 have been hydrothermally synthesized and characterized by single crystal X-ray diffraction, thermogravimetric analysis, IR spectroscopy, and elemental analysis. The structure of Cu-VBPO1 contains a layer anion, {$[Cu(C_2H_8N_2)_2]_3[V_2P_2BO_{12}]_6$}$^{12-}$, whereas Cu-VBPO2 has an open framework anion, {$[Cu(C_2H_8N_2)_2]_5[V_2P_2BO_{12}]_6$}$^{8-}$. Crystal Data: $(NH_4)(C_2H_{10}N_2)_{5.5}[Cu(C_2H_8N_2)_2]_3[V_2P_2BO_{12}]_6{\cdot}17H_2O$, monoclinic, space group I2/m (no. 12), $\alpha$ = 15.809(1) $\AA$, b = 31.107(2) $\AA$, c = 12.9343(8) $\AA$, $\beta$ = 104.325(1)$^{\circ}$, Z = 2; $(NH_4)(C_2H_{10}N_2)_{3.5}[Cu(C_2H_8N_2)_2]_5[V_2P_2BO_{12}]_6{\cdot}18H_2O$, tetragonal, space group $P4_2$/mnm (no.136), $\alpha$ = 26.832(1) $\AA$, c = 18.021(1) $\AA$, Z = 4.

• 대한수학회지
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• 제42권4호
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• pp.621-634
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• 2005

Let$P{\rightarrow}M$ be an oriented $S^2-fiber$ bundle over a closed manifold M and let Q be its associated SO(3)-bundle, then we investigate the ring structure of the cohomology of the total space P by constructing the coupling form TA induced from an SO(3) connection A. We show that the cohomology ring of total space splits into those of the base space and the fiber space if and only if the Pontrjangin class $p_1(Q)\;{\in}\;H^4(M;\mathbb{Z})$ vanishes. We apply this result to the twistor spaces of 4-manifolds.

• 대한수학회지
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• 제32권3호
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• pp.471-482
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• 1995

A complex n-dimensional Kaehlerian manifold of constant holomorphic sectional curvature c is called a comples space form, which is denoted by $M_n(c)$. A complete and simply connected complex space form consists of a complex projective space $P_nC$, a complex Euclidean space $C^n$ or a complex hyperbolic space $H_nC$, according as c > 0, c = 0 or c < 0. The induced almost contact metric structure of a real hypersurface M of $M_n(c)$ is denoted by $(\phi, \zeta, \eta, g)$.

• 대한수학회보
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• 제34권2호
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• pp.173-184
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• 1997

An n-dimensional complex space form $M_n(c)$ is a Kaehlerian manifold of constant holomorphic sectional curvature c. As is well known, complete and simply connected complex space forms are a complex projective space $P_n C$, a complex Euclidean space $C_n$ or a complex hyperbolic space $H_n C$ according as c > 0, c = 0 or c < 0.

• 대한수학회지
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• 제32권4호
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• pp.835-848
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• 1995

Let $M_n$(c) be an n-dimensional complete and simply connected Kahlerian manifold of constant holomorphic sectional curvature c, which is called a complex space form. Then according to c > 0, c = 0 or c < 0 it is a complex projective space $P_nC$, a complex Euclidean space $C^n$ or a complex hyperbolic space $H_nC$.

• 대한수학회논문집
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• 제9권2호
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• pp.369-383
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• 1994

A complex n-dimensional Kahler manifold of constant holomorphic sectional curvature c is called a complex space form, which is denoted by $M_{n}$ (c). A complete and simply connected complex space form consists of a complex projective space $P_{n}$ C, a complex Euclidean space $C^{n}$ or a complex hyperbolic space $H_{n}$ C, according as c > 0, c = 0 or c < 0.(omitted)

• Bulletin of the Korean Chemical Society
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• 제18권2호
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• pp.213-217
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• 1997

Magnesium reduction of Mo(N-C6H3-2,6-i-Pr2)2Cl2(DME) in the presence of trimethylphosphine led to a mixture of Mo(N-C6H3-2,6-i-Pr2)(PMe3)2Cl3, 1, and Mo2(PMe3)4Cl4, 2. In solution 1 is slowly air-oxidized to Mo(N-2,6-i-Pr2-C6H3)(OPMe3)(PMe3)Cl3, 3. 1 is chemically inert to carbon nucleophiles (ZnMe2, ZnEt2, AlMe3, AlEt3, LiCp, NaCp, TlCp, NaCp*, MeMgBr, EtMgBr), oxygen nucleophiles (LiOEt, LiO-i-Pr, LiOPh, LiOSPh), and hydrides (LiBEt3H, LiBEt3D). Crystal data for 1: orthorhombic space group P212121, a=11.312(3) Å, b=11.908(3) Å, c=19.381(6) Å, Z=4, R(wR2)=0.0463 (0.1067). Crystal data for 2: monoclinic space group Cc, a=18.384(3) Å, b=9.181(2) Å, c=19.118(3) Å, b=124.98(1)°, Z=4, R(wR2)=0.0228 (0.0568). Crystal data for 3: orthorhombic space group P212121, a=11.464(1) Å, b=14.081(2) Å, c=16.614(3) Å, Z=4, R(wR2)=0.0394 (0.0923).

• Bulletin of the Korean Chemical Society
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• 제25권7호
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• pp.986-990
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• 2004

Condensation of salicylaldehyde $(2-HOC_6H_4C(O)H)$ with allylamine afforded the unsaturated salicylaldimine, $2-HOC_6H_4C(H)=NCH_2CH=CH_2$. Similar reactivity was observed with substituted salicylaldehydes. Further reaction of these Schiff bases with palladium acetate or $Na_2PdCl_4$ afforded complexes of the type $PdL_2$, where L = deprotonated Schiff base. The molecular structure of the parent salicylaldimine palladium complex $[trans-(2-OC_6H_4C(H)=NCH_2CH=CH_2)_2Pd]$ (1) was characterized by an X-ray diffraction study. Crystals of 1 were monoclinic, space group $P2_1/n,\;a\;=\;14.0005(9)\;{\AA},\;b\;=7.2964(5)\;{\AA},\;c\;=\;17.5103(12)\;{\AA},\;{\beta}\;=\;100.189(1)^{\circ}$, Z = 4. Analogous chemistry with 4-vinylaniline also gave novel palladium complexes containing a pendant styryl group. Crystals of $[trans-(2-HOC_6H_4C(H)=N-4-C_6H_4CH=CH_2)_2Pd]$ (4) were monoclinic, space group $P2_1/c$, a = 13.7710(14) ${\AA}$, b = 11.0348(11) ${\AA}$, c = 7.8192(8) ${\AA}$, ${\beta}\;=\;98.817(2)^{\circ}$, Z = 2.

• 대한수학회논문집
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• 제11권1호
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• pp.153-167
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• 1996

In this paper we investigate the existence of solutions of a nonlinear wave equation $u_{tt} - u_{xx} = p(x, t, u)$$ in $H_0$, where $H_0$ is the Hilbert space spanned by eigenfunctions. If p satisfy condition $(p_1) - (p_3)$, this nonlinear gave equation has at least one solution.

• 한국미생물·생명공학회지
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• 제25권3호
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• pp.258-265
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• 1997

The effects of medium pH and culture temperature on the expression and secretion of inulinase and invertase were investigated with recombinant Saccharomyces cerevisiae cells. These cells were obtained by transformation of 2$\mu$-based plasmids pYI10 and pYS10 which contain Kluyveromyces marxianus inulinase gene (INU1A) and S. cerevisiae invertase gene (SUC2), respectively, in the downstream of GAL1 promoter. The expression level and localization of inulinase and invertase were not affected significantly by the initial medium pH: secretion efficiencies of inulinase and invertase into the medium were about 90% and 60%, respectively, in the pH ranges of 4.0 to 6.5. However, the expression and secretion of both enzymes were strongly dependent on the culture temperature. The highest expression (7.7 units/mL) and secretion (6.7 units/mL) of inulinase were observed at 28$\circ$C and 30$\circ$C. As a consequence of decreased localization of inulinase in the periplasmic space, the secretion efficiency increased from 68% at 20$\circ$C, to 95% at 35$\circ$C,. The total expression level and secretion efficiency of invertase increased from 19 units/mL and 55% at 20$\circ$C to 25 units/mL and 68% at 35$\circ$C, respectively. Irrespective of the culture temperature, the invertase activity in the cellular fraction (periplasmic space and cytoplasmic fractions) was kept constant at around 33-45%.