• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.332-332
• /
• 2006

Well difined sulfonated styrene and n-butyl acrylate (nBA) block copolymers were synthesized by CuBr catalyzed living radical polymerization followed by acification by thermolysis. Neopentyl styrene sulfonate (NSS) was polymerized with PnBA macroinitator precursor ($M_{n}=19,500,\;PDI\;<\;1.09$) and CuBr catalyst with N,N,N',N' -pentamethylethyleneamine (PMDETA) to give nBA-NSS block copolymer with narrow polydispersity ($M_{n}=29,900,\;PDI\;<\;1.15$). PNSS segments in the block copolymer were then acidified by thermolysis at $150^{\circ}C$ resulting in polystyrene segments with 100 % sulfonic acid groups.

• Journal of the Korean Chemical Society
• /
• v.16 no.1
• /
• pp.6-12
• /
• 1972

The crystal structure of monoethanolamine hydrochloride is triclinic P1 with two formula units in a cell of dimensions a = $4.42\pm0.02$, b = $7.44\pm0.02$, c = $7.48\pm0.02$, $\alpha$ = $102.4\pm0.3$, $\beta$ = $91.1\pm0.3$, $\gamma$ = $77.2\pm0.3^{\circ}.$ The configuration of monoethanolamine is a gauche form with dihedral angle, $90^{\circ}$. The nitrogen atom forms four hydrogen bonds, three to Cl- ions(3.15, 3.24, $3.28\AA)$ and one to a hydroxyl group of another molecule (N${\cdot}{\cdot}{\cdot}$O, $2.90{\AA})$. The oxygen also forms two such bonds, one to a Cl- ion $(3.14\AA)$, one to an amine group of another molecule (O${\cdot}{\cdot}{\cdot}$N, $2.90{\AA}).$ Molecules are linked into two-dimensional network by hydrogen bonds.

• Korean Journal of Crystallography
• /
• v.11 no.1
• /
• pp.42-45
• /
• 2000

The complex [Zn(L)Cl](H₂O)(ClO₄) (1) (L=3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,O/sup 1.18/,O/sup 7.12/]docosane) has been prepared and characterized by X-ray crystallography. 1 crystallizes in the monoclinic space group P2₁/c, with a=8.883(1), b=19.319(9), c=15.124(2)Å, β=101.65(1)°, V=2542.0(13) ų, Z=4, R₁(wR₂) for 4457 observed reflections of [I>2σ(I)] was 0.0640(0.1557). The coordination geometry around the zinc is a distorted square-pyramid with four nitrogen atoms of the macrocycle occupying the basal sites(Zn-N/sub av/=2.131(2)Å) and a chloride atom at the axial position with the Zn-Cl distance of 2.315(2)Å.

• Journal of the Korean Chemical Society
• /
• v.16 no.4
• /
• pp.214-218
• /
• 1972

The quadratic force constants of heteronuclear diatomic molecules, LiH, BeH, BH, CH, NH and OH are evaluated by use of the one center function of Bishop et. al. The master formula on which the computation is based was suggested by the previous work of one of the present authors. The results are in good agreement with the experimental values. It is found that around the nucleus of the atom located in the close vicinity of the expansion center of the one center function, the electronic distribution is relatively unrealistic, and the suggested formula would lead an erroneous result when one takes the origin of variables of $P_2(cos{\theta})/r_3$ at the atomic nucleus.

• Journal of the Korean Chemical Society
• /
• v.7 no.1
• /
• pp.74-84
• /
• 1963

Hexamethylenediamine dihydroiodide is monoclinic, with cell dimensions $a=4.85{\AA}$, $b=12.77{\AA}$, $c=9.73{\AA}$, ${\beta}=91.5^{\circ}$ The space group is $P2_1/c$, with two molecules per unit cell. It has a center of symetry in the molecule. All atomic positions are determined by means of a two-dimensional patterson synthesis and fourier synthesis. The C-N bond distance is $1.48{\AA}$ and the C-C bond distances are lying between $1.55{\AA}$, and $1.59{\AA}$. The iodine atom is bonded by hydrogen bridges of $3.59{\AA}{\pm}0.1{\AA}$ to nitrogen atoms and surrounded by three nitrogen atoms. The hexamethylenediamine chain is zigzag in the hexamethylenediamine dihydrochloride molecules though, it is not zigzag in the hexamethylenediamine dihydroiodide.

• Bulletin of the Korean Chemical Society
• /
• v.24 no.2
• /
• pp.167-172
• /
• 2003

Alkyliron(Ⅲ) porphyrins, n-butyliron(Ⅲ) tetraphenylporphyrin, (TPP)Fe-Bu and n-butyliron(Ⅲ) tetrakis-(pentafluorophenyl)porphyrin, $(F_{20}TPP)Fe-Bu$ have been evaluated as suitable for olefin free-radical polymerization. Butyl radicals dissociated from n-butyliron(Ⅲ) porphyrin initiated the polymerization reaction, but the ratio of the propagation was low. The GCMS analysis of the reaction mixture of nbutyliron(Ⅲ) porphyrin and styrene has revealed several products containing two butyl groups, while traces of b-hydrogen-abstracted products were observed. The crystal structure of (TPP)Fe-Bu has been determined. The structure of the n-butyliron(Ⅲ) porphyrin reveals the compound containing five-coordinated iron with the average Fe-N distance of 1.973(1) Å and Fe-C of 2.030(2) Å. The iron atom is displaced by 0.137Å from a four nitrogen mean plane. Crystal system is triclinic, and space group is P-1.

• Bulletin of the Korean Chemical Society
• /
• v.32 no.12
• /
• pp.4387-4391
• /
• 2011

The kinetic studies on the pyridinolysis of diisopropyl thiophosphinic chloride have been carried out in acetonitrile at $55.0^{\circ}C$. The free energy correlations for substituent X variations in the X-pyridines are biphasic concave upwards with a break point at X = 3-Ph. A concerted SN2 mechanism is proposed with a change of the attacking direction of the X-pyridine from a frontside attack for the strongly basic pyridines to a backside attack for the weakly basic pyridines. The factors to determine the rates and thio effects on the rates for the pyridinolyses of thiophophinic chloride, chlorothiophosphate, phosphinic chloride, phosphonochloridothioate, and chlorophosphate systems are briefly reviewed on the basis of the magnitude of the positive charge of the reaction center P atom and steric effects of the two ligands.

• Journal of Applied Biological Chemistry
• /
• v.49 no.3
• /
• pp.86-89
• /
• 2006

The novel tetranuclear nickel (II) complex is a high rate accelerator in promoting hydrolysis of phosphate diesters. Nickel-bound bis-nitrophenyl phosphate (BNPP) can be $10^4$ times more reactive than the unbound BNPP. The large rate of enhancements by the complex slightly under basic condition has shown high catalytic activity in phosphate diester cleavage. The bell-shaped pH-rate profile indicated that the nickel-oxide form of the tetranuclear complex or its kinetic equivalent was the active species for cleaving BNPP. The catalytic hydrolysis between tetranuclear nickel (II) complex and phosphate diester proceeds via the formation of bidentate coordination of the anionic phosphate to the Ni (II) atom. This reveals that the complex has the possibility as artificial nuclease.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2011.02a
• /
• pp.203-203
• /
• 2011

Metastable statates, resonant states in 4s level and excited states in 4p level were investigated with a simple global model and examined by the LIF experiments. Metastable states exhibit an anomalous behavior with the plasma density, on the other hands, other states show monotonous increasing behaviors. It turns out that the metastable state can have such an anomalous behavior due to its special characteristic, electric dipole radiation forbidden. It is expected to resolve the ambiguity of previously reported metastable density behaviors and provide further understanding.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1996.11a
• /
• pp.221-224
• /
• 1996

We synthesized amphiphilic material including dye skeleton, p-phenylenediamine(PD) by attaching norma-decyl group of two strands at a part of coordinating atom, for obtaining reasonable design of LB uniform films. The synthesis of this compounds was quantitatively carried out under ultra pure state. This product was identified with FT-lR spectroscopy, UV absortion spectroscopy, and $^1$H-NMR spectroscopy, respectively. When manufacturing monolayer, we confirmed molecular area from pressure-area($\pi$-A) cutie of thiscompound onto the surface of the water. The spectroscopic approach also has done by UV absortion spectroscopy. It was shown that PD-complex LBfilms were deposited well with monolayer thickness. The conductivity based on I-V characteristics of PD-complex LB films were in the range of 10$^{-10}$ S/cm at room temperture. The microscopic properties by AFM, showed the good orientation of various monolayer or multilayer molecules