• Asian-Australasian Journal of Animal Sciences
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• v.8 no.6
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• pp.627-633
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• 1995

This experiment was designed to evaluate the effect of various dietary vitamin $B_6$ levels on conversion from linoleic acid to arachidonic acid in various tissues in growing chicks. Growing chicks were fed the purified diet containing 7% safflower oil with different levels of vitamin $B_6$ (0, 4, 8, 40, 80 mg per kg diet) for 14 days. Feed intake and weight gain in chicks fed the vitamin $B_6$-free diet were markedly depressed. Esterified and free cholesterol concentrations in serum were significantly higher, while the serum triglyceride concentration was significantly lover in chicks fed the vitamin $B_6$-free diet compared to that fed diets with vitamin $B_6$. The liver triglyceride content was also lower in chicks fed the vitamin $B_6$-free diet. The liver and serum cholesterol ester fractions in chicks fed the vitamin $B_6$-free diet showed higher rate of $C_{18:2n6}$ and lower rates of $C_{18:3n6}$, $C_{20:3n6}$ and $C_{20:4n6}$ as compared with vitamin $B_6$ fed groups. In serum phospholipid fraction of chicks fed the vitamin $B_6$-free diet, rates of $C_{20:3n6}$ and $C_{20:4n6}$ were markedly lower. As dietary vitamin $B_6$ level was increased, the rate of $C_{20:4n6}$ was slightly increased, although it was statistically not significant. The fatty acid compositions of adipose tissue showed almost the same pattern as those in liver and serum. This result suggests that the desaturation of $C_{18:2n6}$ to $C_{18:3n6}$, elongation to $C_{20:3n6}$ or both steps might be impaired by vitamin $B_6$ deficiency in growing chicks.

• Bulletin of the Korean Chemical Society
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• v.21 no.4
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• pp.379-382
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• 2000

The temperature dependence of the kinetic parameters of the aspartase-catalyzed reaction has been examined in the direction of deamination. The pK1values at 37$^{\circ}C$, 25$^{\circ}C$, 16$^{\circ}C$ and 7$^{\circ}C$ were 6.2 $\pm$ 0.1, 6.3 $\pm$ 0.1, $6.7{\pm}0.3$ and 6.9 $\pm$ 0.3, respectively. On the other hand, the pK2 values at 37$^{\circ}C$,25$^{\circ}C$, 16$^{\circ}C$ and 7$^{\circ}C$ were 8.1 $\pm0.2$, 8.3 $\pm$ 0.2, 8.2 $\pm$ 0.3 and 8.0 $\pm$ 0.2,respectively. The enthalpy of ionization, DHion, calculated from the slope of pK1, are 6.0 $\pm$ 0.3 kcal/mol. These results validate the prediction that aspartase requires a histidine residue for a general base, and a cysteine (or having a carboxyl functional group) for a general acid.

• Journal of the Korean Chemical Society
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• v.14 no.2
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• pp.193-199
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• 1970

Further validity of the significant structure theory has been tested by calculating the viscosities of binary mixtures-three pairs of $C_6H_6(1)+C_6H_{12}\;(2),\;CCI_4\;(1)+C_6H_6{2}and\l;CCI_4(1)+C_6H_{12}(2)$-and also by calculating the viscosities of n-$C_5H_{12}\;and\;n-C_6H_{14}$ in the pressure range of 1 bar to 4000 bars. The results are quite satisfactory for both cases and provide another evidence for the validity of the significan structure theory.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.6
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• pp.398-403
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• 2001

In this paper, effective ionization coefficient for 6H-SiC is determined. Analytical formulas for the parallel plane breakdown voltage of the 6H-SiC p＋n junction are derived by employing the ionization coefficients. The analytical breakdown voltages show good agreement with the numerical results of Dmitriev＇s［3］and the experimental results of Cree Research［9］over the doping range from 10$^{15}$ cm$^{-3}$ to 10$^{18}$ cm$^{-3}$.

• Journal of the Korean Chemical Society
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• v.55 no.2
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• pp.183-188
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• 2011

The electronic structure and properties of Ni$(C_6H_{4-n}F_n)(CO)_2$ ($C_6H_4$=benzyne, n=1-4) complexes have been investigated using hybrid density functional B3LYP theory. Both aromatic natures and nucleus independent chemical shift (NICS) of the benzyne rings have been analyzed. Among mono-, di-, and tri-fluorinated complexes, 3-F, 3,6-F, and 4-H are the most stable isomers, respectively. NICS values calculated at the several points above the ring centers are consistent with those based on the relative energies of the complexes. The atoms in molecules (AIM) analysis indicates that Ni-C bond distance is well correlated with the electron density of a ring critical point (${\rho}_{rcp}$) in all species.

• Advances in materials Research
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• v.6 no.3
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• pp.303-316
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• 2017

In this article, novel olefin polymerization catalyst with lower cost and simple synthetic process were developed, $ArOTiCl_3$ complexes [$(2-OMeC_6H_4O)TiCl_3(C1)$, $(2,4-Me_2C_6H_3O)TiCl_3(C2)$, $TiCl_3(1,4-OC_6H_4O)TiCl_3(C3)$, $TiCl_3(1,4-OC_6H_2O-Me_2-2,5)$ $TiCl_3(C4)$] and corresponding $(ArO)_2TiCl_2$ complexes [$TiCl_2(OC_6H_4-OMe-2)_2(C5)$ and $TiCl_2(OC_6H_3-Me_2-2,6)_2(C6)$] have been synthesized by the reaction of $TiCl_4$ with phenol, all these complexes were well characterized with $^1H$ NMR, $^{13}C$ NMR, MASS and EA. When combined with methylaluminoxane (MAO), the $ArOTiCl_3/MAO$ system shows high activity for ethylene copolymerization with 1-octene and copolymer was obtained with broaden molecular weight distribution (MWD). The $^{13}C$ NMR result of polymer indicates that the 1-octene incorporation in polymer reached up to 8.29 mol%. The effects of polymerization temperature, concentration of polymerization monomer and polymerization time on the catalytic activity have been investigated.

• Bulletin of the Korean Chemical Society
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• v.12 no.6
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• pp.604-606
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• 1991

From O-glucuronyl trichloroacetimidate (4) and ${\Delta}^6$-tetrahydrocannabinol (5), the C-glucuronide of ${\Delta}^6-tetrahydrocannabinol({\Delta}^6-THC)$ (7) was obtained using mild Lewis acid catalysis. The known method for the synthesis of C-glucuronide from 1-O-unprotected glucuronide provided low chemical yields. The C-glucuronide of ${\Delta}^6-THC$ was obtained through inversion of configuration at the anomeric center in O-glucuronyl trichloroacetimidate (4).

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.1817-1820
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• 2015

Background: Hemoglobin A1c(HgA1c) is a marker of poor gylcemic control and elevation HgA1c is associated with increased risk of many cancers. We aimed to determine the HgA1c levels in endometrial cancer cases and any relationship with stage and grade of disease. Materials and Methods: A retrospective data review was performed between June 2011 and October 2012 at a tertiary referral center in Turkey. The study included 35 surgically staged endometrial cancer patients and 40 healthy controls. Preoperative HgA1c levels drawn within 3 months before surgery were compared. Also the relationships between HgA1c levels and stage, grade and hystologic type of cancer cases were evaluated. Results: The mean HgA1c levels were statistically significantly higher at $6.19{\pm}1.44$ in endometrial cancer cases than the $5.61{\pm}0.58$ in controls (p=0.027). With endometrial cancer cases, the mean HgA1c level was found to be $6.62{\pm}1.40$ for stage I and $6.88{\pm}1.15$ for stages II-IV (p=0.07). The figures were $6.74{\pm}1.65$ for endometrioid and $6.63{\pm}1.41$ for non-endometrioid type tumors (p=0.56). Mean HgA1c levels of $6.72{\pm}1.14$ for grade 1 and $6.62{\pm}1.42$ for grade 2-3 were observed (p=0.57). Conclusions: HgA1c levels in endometrial cancer patients were statistically higher than healthy controls. However, HgA1c did not show any significant correlation with stage, grade and histologic type in endometrial cancer cases.

• Korean Journal of Materials Research
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• v.11 no.5
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• pp.431-437
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• 2001

This research was examined the effect of intercritical heat treatment on the mechanical Properties and retained austenite formation in 0.1C-6.5Mn steels for the development of a high strength high ductility steel. using of transformation induced plasticity due to retained austenite. The stability of retained austenite is very important for the good ductility and it depend on diffusion of carbon and manganese during reverse transformation. It is effective to heat treat at$ 645^{\circ}C$ in order to obtain over 30 vol.% of retained austenite. However, it is more desirable to heat treat at $620^{\circ}C$, considering the volume fraction and mechanical stability of retained austenite. The strength-elongation combination in cold rolled steel sheets after reverse transformed at $620^{\circ}C$ for 1hr was about 4000k9/mm7, but it decreased rapidly with increasing holding time at high temperature due to the decrease of ductility. The addition of 1.1%Si in 0.14C-6.5Mn TRIP steel does not improve the mechanical properties and retained austenite formation.

• Korean Journal of Optics and Photonics
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• v.4 no.2
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• pp.195-199
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• 1993

The output energy of Rh-6G dye laser was enhanced by the energy transfer in the mixture of Rh-6G and C-545. The laser was pumped by coaxial flashlamp filled argon gas. The optimum concentration of Rh-6G was $10_-4mol/l$ without mixing. The output energy was enhanced about 70 % at 0.4 % C-545 mixture with respect to the concentration of Rh-6G. The peak output power and the output energy were 27 kW and 50 mJ at the pumping energy of 346 J.