• Bulletin of the Korean Chemical Society
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• v.18 no.4
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• pp.402-405
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• 1997

Olefinic and cyclopropyl group substituted arenes (C6H5Y) react with [Cp*Ir(CH3COCH3)3]A2 (A=ClO4-, OTf-) to give η6-arene complexes, [Cp*Ir(η6-C6H5Y)]2+ (1a: Y=-CH=CH2 (a),-CH=CHCH3 (b),-C(CH3)=CH2 (c),-CH-CH2-CH2 (d)). Complex 1b-1d are readily converted into η3-allyl complexes, [Cp*(CH3CN)Ir(η3-CH(C6H5)CHCH2)]+ (2a) and [Cp*(CH3CN)Ir(η3-CH2(C6H5)CH2)]+ (2b), in the presence of Na2CO3 in CH3CN. The η6-styrene complex, 1a reacts with NaBH4 to give η5-cyclohexadienyl complex, [Cp*Ir(η5-C6H6-CH=CH2)]+ (3), while with H2 it gives η6-ethylbenzene complex [Cp*Ir(η6-C6H5CH2CH3)]2+ (4). Complex 1a and 1c react with HCl to give [Cp*Ir(η6-C6H5CH2CH2Cl)]2+ (5a) and [Cp*Ir(η6-C6H5CH(CH3)CH2Cl]2+ (5b), respectively.

• Progress in Superconductivity
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• v.12 no.2
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• pp.104-109
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• 2011

We have investigated the anisotropy of the superconducting properties for $CaC_6$ and $SrC_6$ using upper critical fields ($H_{c2}$) and specific heat ($C_p$). From the upper critical fields of $CaC_6$ at different magnetic field orientations, H//c and H// ab, the anisotropy is found to be ~ 5 at low temperatures, much larger than that of $SrC_6$. These results are in contrast to the stronger anisotropy in the electronic structure for $SrC_6$ than for $CaC_6$ indicating a stronger anisotropy in the superconducting gap in $CaC_6$. The findings are confirmed by the temperature dependence of the superconducting specific heat below $T_c$ for $CaC_6$ and $SrC_6$, suggesting the important role of anisotropic electron-phonon coupling in superconducting intercalated graphites.

• Bulletin of the Korean Chemical Society
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• v.17 no.9
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• pp.802-807
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• 1996

Second-order rate constants have been measured spectrophotometrically for the reactions of aryl benzoates (X-C6H4CO2C6H4-Y) with EtO-, Z-C6H4O- and Z-C6H4C(Me)=NO- in absolute ethanol at 25.0 ℃. All the reactions have been performed in the presence of excess 18-crown-6 ether in order to eliminate the catalytic effect shown by alkali metal ion. A good Hammett correlation has been obtained with a large ρ- value (-1.96) when σ- (Z) constant was used for the reaction of p-nitrophenyl benzoate (PNPB) with Z-C6H4O-. Surprisingly, the one for the reaction of PNPB with Z-C6H4C(Me)=NO- gives a small but definitely positive ρ- value (＋0.09). However, for reactions of C6H5CO2C6H4-Y with EtO-, correlation of log k with σ- (Y) constant gives very poor Hammett correlation. A significantly improved linearity has been obtained when σ0 (Y) constant was used, indicating that the leaving group departure is little advanced at the TS of the RDS. For reactions of X-C6H4CO2C6H4-4-NO2 with EtO-, C6H5O- and C6H5C(Me)=NO-, correlations of log k with σ (X) constants for all the three nucleophile systems give good linearity with large positive ρ values, e.g. 2.95, 2.81 and 3.06 for EtO-, C6H5O- and C6H5C(Me)=NO-, respectively. The large ρ values clearly suggest that the present reaction proceeds via a stepwise mechanism in which the formation of the addition intermediate is the RDS.

• Journal of the Korean Chemical Society
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• v.34 no.6
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• pp.517-526
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• 1990

The crystal structures of two alditol acetates, D-glucitol hexaacetate and xylitol pentaacetate, have been determined by diffraction methods with Mo-K$\alpha$radiation, using direct methods for phase determinations. The crystal data are: for D-glucitol hexaacetate, P2$_1$, with a = 10.275 (2), b = 8.363 (1), c = 12.560 (5) $\AA;\beta$ = 95.97 $(2)^{\circ}$, Z = 2; for xylitol pentaacetate, P2$_1$/C with a = 18.126 (1), b = 11.422 (2), c = 8.649 (1) $\AA$, $\beta = 95.03 (1)^{\circ}$, Z = 4. Both molecules have extended zigzag carbon chain conformations which differ from previous studies of the structures of D-glucitol and xylitol and also differ from NMR studies on alditol acetates. The bond lengths and angles are normal, with mean values over both structures of C($sp^3)-C(sp^3): 1.514 (10),\; C(sp^3)-O: 1.444 (6),\; C(sp^2)-O: 1.347 (9),\; C(sp^2)=O: 1.197 (6),\; C(sp^2)-C(sp^3): 1.479(9){\AA},\; C(sp^3)-C(sp^3)-C(sp^3): 114.6 (17),\; O-C(sp^3)-C(sp^3): 109.4 (23),\; C(sp^2)-O-C(sp^3): 117.4 (6),\; O=C(sp^2)-O: 122.6 (6),\; C(sp^3)-C(sp^2)-O: 111.8 (7),\; C(sp^3)-C(sp^2)=O: 125.5 (4)^{\circ}$. The atoms of acetate groups are in coplanar. There are no particularly short intermolecular contacts and the molecules are held together by van der Waals force only.

• Membrane Journal
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• v.24 no.4
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• pp.259-267
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• 2014

PEBAX[poly(ether-block-amide)-ZIF-8(zeolitic imidazolate framework) composite membranes were prepared with different amounts of ZIF-8; 0, 1, 3, 7, 10, and 20 wt%. Gas permeation experiment were performed by varying the temperature of 25, 35, $40^{\circ}C$ under condition $6kgf/cm^2$. Gas permeability of $C_3H_6$, $C_3H_8$ and selectivity ($C_3H_6/C_3H_8$) were investigated by increasing the amount of ZIF-8 in the PEBAX. The gas permeability of $C_3H_6$ and $C_3H_8$ increased as ZIF-8 content increased among 0 to 7 wt% range and decreased among 7 to 20 wt% range. When the ZIF contents of PEBAX-ZIF composite membrane were 7 wt%, the selectivity ($C_3H_6/C_3H_8$) was taken between 3.6 and 3.8 value and also had the lowest activation energy.

• Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.69-72
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• 2012

Effects of dietary nutrient content on the biological index and serum chemistry of olive flounder Paralichthys olivaceus achieving compensatory growth were investigated. Six treatments were prepared in triplicate. Fish were hand-fed with the control (C) diet twice daily for 8 weeks (8W-C) or fish were starved for 2 weeks and then hand-fed with the C, high protein (HP), high carbohydrate (HC), high lipid (HL), or intermediate protein, carbohydrate and lipid (IPCL) diets for 6 weeks, referred to as 6W-C, 6W-HP, 6W-HC, 6W-HL, and 6W-IPCL, respectively. Weight gain of fish in the 8W-C, 6W-HP, and 6W-IPCL treatments was higher than that of fish in the 6W-C treatment. Condition factor (CF) of the fish in the 6W-HP, 6W-HC and 6W-IPCL treatments was higher than that of fish in the 8W-C and 6W-C treatments. The hepatosomatic index (HSI) of fish in the 6W-HC, 6W-HL and 6W-IPCL treatments was higher than that of the fish in the 8W-C, 6W-C and 6W-HP treatments. Serum chemistry except triiodothyronine ($T_3$) was not significantly different among the treatments. In conclusion, CF and HSI of the fish could be indices reflecting compensatory growth, whereas $T_3$ seemed to play a partial role in achieving compensatory growth.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.9
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• pp.1248-1255
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• 2009

This study was carried out to evaluate the fatty acid composition in Nellore cows supplemented with either linseed (n-3) or canola grains (n-6 and n-9). Fifteen Nellore cows, aged five years and bodyweight 550 kg${\pm}$48 kg, were randomly distributed to the following treatments: CON (control), LIN (linseed) and CAN (canola grains). The cows were fed for 80 days. The concentrations of C18:0, C18:2 n-6 and C20:3 n-6 fatty acid were higher (p<0.10) in CON blood plasma in comparison to follicular liquid. Likewise, PUFA, n-6 contents, PUFA:SFA and n-6:n-3 ratios were higher (p<0.10) in blood plasma. On the other hand, C18:1 n-9, C22:5 n-3, MUFA and n-3 contents were lower (p<0.10) in blood plasma. C18:0, C18:2 n-6, C18:3 n-3, C22:5 n-3, PUFA, n-6, n-3 contents and PUFA:SFA ratio were higher (p<0.10) in LIN blood plasma than in the follicular liquid. Nevertheless, C14:0, C16:0, C16:1 n-7, PUFA, C16:0, C18:1 n-9 and MUFA contents were lower (p<0.10) in LIN blood plasma. On treatment CAN, the C18:0 and SFA contents, and n-6:n-3 ratios were higher (p<0.10) in blood plasma. However, C20:3 n-6, C22:5 n-3, PUFA and n-3 contents were lower (p<0.10) in blood plasma. C16:0, C18:0, PUFA, SFA contents and PUFA:SFA ratio did not differ (p>0.10) among the treatments. C14:0, C16:1 n-7, C18:2 n-6 and n-6 contents were higher (p<0.10) for CON and CAN than LIN. C17:1 n-7, C20:4 n-6 and C 22:0 contents were higher (p<0.10) for CAN than CON and LIN. C18:1 n-9, C18:3 n-3, MUFA and n-3 contents were higher (p<0.10) for LIN and CAN than CON. C20:3 n-6 content and n-6:n-3 ratio were higher (p<0.10) for CON than LIN and CAN. C22:5 n-3 content were higher (p<0.10) for CON and LIN than CAN. The concentrations of fatty acids in blood plasma and follicular liquid were not correlated for any fatty acid, independent of the treatment studied. Canola grain added to the diet of Nellore cows resulted in increased concentrations of fatty acids n-6 and n-3 in follicular liquid.

• Journal of Korean Ophthalmic Optics Society
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• v.6 no.1
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• pp.43-47
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• 2001

The classifying distribution by the Spherical lens and Aspherical lens was middle myopic, middle myopic astigmatism middle mixed astigmatism compared. The refractive erroeye spherical lens were S-3.00 ~ S-6.00Dptr for the middle myopic 16%, S-6.00Dptr 19%, S-3.00C-0.50(90.180) ~ S-6.00C-2.00Asix(90.180)57%, S-3.00C+0.50(90.180) ~ S-6.00C+2.00Axis(90.180) 8% for the compound myopic astigmatism. Aspherical lens were S-3.00 ~ S-6.00Dptr for the middle myopic 31%, S-6.00Dptr 36%, S-3.00C-0.50(90.180) ~ S-300C-2.00Axis(90.180) 21%, S-3.00C+0.50(90.180) ~ S-3.00C+2.00Axis(90.180)12%, for the compound hyperopic astigmatism.

• Journal of the Korean Chemical Society
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• v.15 no.3
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• pp.133-145
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• 1971

A method of theoretical calculation of the thermodynamic properties for liquid-vapor interface of binary solution is developed according to the transient state theory of significant liquid structure. The surface tensions, the adsorbed amounts at the liquid-vapor interface and the activity coefficients of the components for the solutions of $C_6H_{12}-C_6H_6$ $CCI_4-C_6H_6$, $CHCl_3-C_6H_6$, $CHCl_3-CCl_4$, $CCl_4-CS_2$ are calculated through the full ranges of the compositions.

• Journal of the Korean Chemical Society
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• v.9 no.4
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• pp.153-160
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• 1965

Ultraviolet spectrophotometric investigations have been carried out on the systems of benzene with iodine, bromine, chlorine and iodine monobromide in carbon tetrachloride. The results reveal the formation of one to one molecular complexes of the type, $C_6H_6{\cdot}X_2\;or\;C_6H_6{\cdot}IX$ (X denotes halogen atoms). The equilibrium constants obtained at $25^{\circ}$for the complex formation are 0.173, 0.137, 0.0643 and 0.341 $lmole^{-1}$ for $C_6H_6{\cdot}I_2,\;C_6H_6{\cdot}Br_2,\;C_6H_6{\cdot}Cl_2\;and\;C_6H_6{\cdot}IBr$, respectively. These results combined with those obtained by other workers indicate that the relative stabilities of the benzene complexes decrease in the order, $ICl > IBr > I_2 > Br_2 > Cl_2.$ This order may be measure of their relative acidities toward benzene, which is explained in terms of the relative polarizabilities of halogen molecules and the relative electronegativities of halogen atoms.