• Bulletin of the Korean Chemical Society
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• 제18권4호
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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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• 제12권2호
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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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• 제17권9호
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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.

• 대한화학회지
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• 제34권6호
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• pp.517-526
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• 1990

D-glucitol hexaacetate 와 xylitol pentaacetate의 결정구조를 단결정 X-선 회절법으로 연구하였다. D-glucitol hexaacetate 는 공간군 P2$_1$, 단위세포 상수는 a = 10.275 (2), b = 8.363 (1), c = 12.560 (5) $\AA$, $\beta$= 95.97 $(2)^{\circ}$; Z = 2이고, xylitol pentaacetate는 공간군이 P2$_1$/C이고, a = 18.126 (1), b = 11.422 (2), c = 8.649 (1) $\AA$, $\beta$ = 95.03 $(1)^{\circ}$이며 Z = 4이다. 회절세기는 diffractomerer로 얻었고, 분자구조는 직접법으로 밝혔으며, 최소자승법으로 정밀화하였다. 두 분자에 결쳐 결합의 평균길이는 C($sp^3)-C(sp^3$)가 1.514 (10), C($sp^3)-O: 1.444 (6),\; C(sp^2)-O: 1.347 (9),\; C(sp^2)=O: 1.197 (6),\; C(sp^2)-C(sp^3): 1.479(9){\AA}$이고, 평균 결합각도는 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}$이다. 두 분자내의 탄소 사슬들은 extended zigzag chain으로 되어 있어 D-glucitol과 xylitol 분자들의 conformation과는 다르다. Acetate group들의 각 원자들은 모두 한 평편상에 놓여있다.

• 멤브레인
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• 제24권4호
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• pp.259-267
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• 2014

PEBAX[poly(ether-block-amide)에 ZIF-8(zeolitic imidazolate framework)의 함량을 0, 1, 3, 7, 10, 20 wt%으로 하여 PEBAX-ZIF 복합막을 제조하였다. 기체투과 실험은 압력 $6kgf/cm^2$ 하에서 25, 35, $40^{\circ}C$로 온도를 달리하여 진행되었고, PEBAX-ZIF 복합막의 ZIF-8 함량 변화에 따른 $C_3H_6$과 $C_3H_8$의 기체투과도와 선택도($C_3H_6/C_3H_8$)를 조사하였다. $C_3H_6$과 $C_3H_8$의 투과기체에 대해 ZIF-8 함량 0~7 wt% 범위에서는 함량이 증가할수록 기체 투과도가 증가하다가 7~20 wt% 범위에서 함량이 증가하면 감소하는 경향을 보였다. 선택도($C_3H_6/C_3H_8$)는 PEBAX-ZIF 7 wt% 복합막에서 3.6~3.8의 값을 가지며, 가장 낮은 활성화에너지 값을 나타냈다.

• Fisheries and Aquatic Sciences
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• 제15권1호
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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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• 제22권9호
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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.

• 한국안광학회지
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• 제6권1호
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• pp.43-47
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• 2001

구면렌즈와 비구면렌즈를 착용한 피검자의 굴절이상을 중등도근시, 중등도 근시성 복난시, 중등도 혼합난시이상의 착용자를 대상으로 비교하였다. 양안 굴절이상의 구면렌즈 착용자는 S-3.00 ~ S-6.00Dptr 가 16%, S-6.00D Dptr 이상이 19%, S-3.00C-0.50(90.180) ~ S-6.00C-2.00DptrAxis(90.180) 이 57%, S-3.00C+0.50 ~ S-6.00C+2.00DptrAxis(90.180)이 8%로 분포되어 나타났으며, 비구면렌즈 착용자는 S-3.00 S-6.00Dptr이 31%,S-6.00Dptr 이상이 36%, S-3.00C-0.50(90.180) ~ S-6.00C-2.00DptrAxis(90.180)이 21%, S-3.00C+0.50(90.180) ~ S-6.00C+2.00DptrAxis(90.180)이 12%로 분포되었다.

• 대한화학회지
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• 제15권3호
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• pp.133-145
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• 1971

액체구조의 천이상태이론을 이성분용액의 액체-증기 계면에 적용하여, $C_6H_{12}-C_6H_6$ $CCI_4-C_6H_6$, $CHCl_3-C_6H_6$, $CHCl_3-CCl_4$, $CCl_4-CS_2$계의 표면장력, 표면흡착량, 표면에서의 활동도 계수들을 계산하였다.

• 대한화학회지
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• 제9권4호
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• pp.153-160
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• 1965

벤젠과 요오드, 브롬, 염소 또는 일브롬화요오드와의 각 系를 사염화탄소 용액에서 分光光度法에 의하여 연구한 결과 $C_6H_6{\cdot}X_2$ 또는 $C_6H_6{\cdot}IX$형의 錯物이 형성됨을 알았다(X는 할로겐 原子를 표시함). 이들 錯物의 생성에 대한 $25^{\circ}$에서의 평형상수는 다음과 같다. $C_6H_6{\cdot}I_2\;0.173lmole^{-1},\;C_6H_6{\cdot}Br_2\;0,137lmole^{-1},\;C_6H_6{\cdot}Cl_2\;0.0643lmole^{-1},\;C_6H_6IBr\;0.341lmole^{-1}.$ 이 결과와 다른 사람들의 결과를 종합하면 벤젠과의 錯物의 상대적 안정도가 다음 순서로 감소함을 알 수 있다. $ICI>IBr>I_2>Br_2>Cl_2$ 이 순서는 그들의 상대적 산도를 의미하며 할로겐 분자의 편극을 및 할로겐 원자의 전기음성도의 차이에 의하여 설명할 수 있다.