• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1012-1020
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• 2009

We developed an efficient three-step synthetic protocol of $\gamma$-hydroxybutenolides starting from the Baylis-Hillman adducts: (i) bromination, (ii) Barbier reaction and (iii) one-pot $K_2CO_3$-mediated synthesis of $\gamma$-hydroxybutenolides. In addition, we showed the synthetic applicability of butenolides including self-dimerization, conjugate addition reaction, and alkylations.

• Proceedings of the KIEE Conference
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• 2007.10a
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• pp.269-270
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• 2007

The COMS(Communication, Ocean & Meteorological Satellite) is the geostationary satellite which will be performing three main objectives such as meteorological service, ocean monitoring and Ka-band satellite communications. This paper reports on the hardware architecture of the system electrical ground support equipment(EGSE) for the COMS satellite. EGSE is used to check out satellite during the development prior to lunch. The EGSE represented in this paper consist of two parts. First, I will deal with the OCOE(Overall Check Out Equipment) system which controls and operates the all EGSE system. In second part, we will introduce the SCOE(Specific Check Out Equipment) systems which can test the specific subsystems of the COMS satellite.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.165-168
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• 2004

In this study, AZO(ZnO:Al) thin film were prepared by FTS(Facing Target Sputtering) system. The electrical, optical and crystallographic properties of AZO thin film with $O_2$ gas flow ratio have been investigated. The thickness, transmittance, crystal structure and resistivity of AZO thin film were measured by a-step, UV-VIS spectrometer, XRD and four-point probe, respectively. As a result AZO thin film deposited with the transmittance over 80% and the resistivity about $10^{-1}\Omega-cm$.

• Korean Journal of Microbiology
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• v.29 no.4
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• pp.238-242
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• 1991

Extracellular laccase secreted from Pleurotus ostreatus was activated by $Cu^{2+}$ and $Cu^{+}$ . The enzyme was strongly inactivated by 8-hydroxyquinoline, potassium cyanide, sodium azide, sodium bisulfite and 2-mercaptoethanol. The two ionogenic groups, which have pKa values of 5.60-5.70 and 6.70-6.85 respectively, were found to relate with the active site of this enzyme. The oxidation reactions were brought about by initial single electron transfer process on the active site. The enzyme was found to be a metalloprotein which had about 3.9 cupric ions per molecule of protein as a prosthetic group. The enzyme showed a strong peak at 605 nm and a weak shoulder at 330 nm in UV-Visible absorption spectrum. Both signals disappeated upon treatment of the enzyme with 4 electron equivalent ascorbate. These results indicate that type I Cu peak and type III Cu shoulder are present in laccase.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.2
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• pp.185-191
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• 2005

An experiment was conducted to study the effect of feeding ammoniated wheat straw treated with HCl on blood biochemical profiles in growing male buffalo (Bubalus bubalis) calves. Twenty-four growing male buffalo calves (one year of age, 88.54${\pm}$3.81 kg average body weight) were divided into three groups in a completely randomized design on the basis of their body weight. Animals in all the three groups were fed on concentrate mixture. In addition, they were offered wheat straw, ammoniated wheat straw (4% urea at 50% moisture level) and HCI treated ammoniated wheat straw (4% urea at 50% moisture level and HCl added to trap 30% of the NH3 evolved) in groups I, II and III, respectively for a period of 180 days, as per Kearl (1982) for body weight gain of 500 g/d. In all diets, concentrate:roughage ratio was fixed at 50:50 and were made isonitrogenous by adjusting CP levels of conc. mixtures. Blood was collected from jugular vein of each buffalo calf at the beginning and subsequently at two months interval of experimental feeding. Due to urea-ammoniation, the CP content of wheat straw increased from 2.90 to 6.96% and addition of HCl along with urea further increased the CP content to 10.09%. In all the three groups, the mean values of plasma glucose (mg %) and serum globulin (g %), showed a decreasing trend, while the mean value of serum TP (g %), serum A:G ratio, serum urea (mg %), serum creatinine (mg %), serum ALP (KA units), SGOT (units/ml.), SGPT (units/ml), serum T$_3$ and T$_4$ (ng/ml) showed an increasing trend with the advancement of feeding period. The cumulative period mean values of serum TP (6.15 to 6.20 g %), serum albumin (3.07 to 3.18, g %), serum globulin (2.98 to 3.09, g %), serum A:G ratio (1.03 to 1.10), serum ALP (23.15 to 23.63, KA units), serum T$_3$ (1.20 to 1.23 ng/ml) and serum T$_4$ (21.33 to 21.88 ng/ml) were comparable among the groups. The cumulative period mean plasma glucose (mg %) in group III (57.28) was similar to groups I (55.31) and II (59.41), however, the cumulative period mean plasma glucose in group II was significantly (p<0.01) higher than group I. The cumulative period mean serum urea (mg %) in group III (47.34) was significantly (p<0.001) higher than group I (38.38) and II (42.24), which were statistically alike. However, the cumulative period mean serum creatinine values (mg %) in groups II (1.43) and III (1.52) were similar and were significantly (p<0.01) higher than group I (1.24). The cumulative period mean SGOT (units/ml) in groups I, II and III was 91.71, 96.04 and 96.64, respectively. Similarly the cumulative period mean SGPT (units/ml) was 19.00, 19.93 and 20.01 in groups I, II and III, respectively. The cumulative period mean values of SGOT (p<0.05) and SGPT (p<0.001) in groups II and III were similar and were significantly higher than group I. The cumulative period mean serum T$_3$ and T$_4$ values in groups I (1.21 and 21.81), II (1.23 and 21.42) and III (1.20 and 21.33) were comparable. From the present study it may be concluded that feeding of AWS treated with and without HCI to growing male buffalo calves for 180 days had no significant adverse effect on blood biochemical profile.

• Korean Journal of Crystallography
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• v.5 no.1
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• pp.14-19
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• 1994

Tlifluoromethyltriphenyl-1,2,4-tioxolane(C2IHlsF303)is triclinic, space group P1 with a=10.477(1), b= 11.056(1), c=9.917(3) A, a=104.7(1), B=122.7(1), r=63.9(1), Z=2, V=867.9(3) A3, Dc=1.43 g/cm3, λ(Mo Ka)=0.71069 A, μ=0.0116 cm-1,F(000)=384, and R=0.067 for 1713 unique observed reflections with I > 1.0 o(I). The structure was solved by direct methods and refined by fall-matrix least-squares refinement with the fixed C-H bond lengths at 0.96 A. Two phenyl rings((2) and (3)) that have the dihydral angle of 106.0°.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.455-462
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• 1995

The new six herbicidal N-[(pyrimidin-2-yl)aminocarbonyl]-2-substituted-6-(1-hydroxy-2-fluoroethyl)benzenesulfonamide derivatives(S) were synthesized and rate constants for the hydrolysis of thier in the range of pH $1.0{\sim}10.0$ have been studied in 15%(v/v) aqueous acetonitrile solution at $45^{\circ}C$. From the basis of the results, pH-effect, solvent effect, ortho-substituent effect, thermodynamic parameters(${\Delta}H^{\neq}$ & ${\Delta}S^{\neq}$), pKa constant(4.80), rate equation, analysis of hydrolysis products(2-(1-hydroxy-2-fluoroethyl)benzenesulfonamide & 4,6-dimethoxyaminopyrimidine), it may be concluded that the general acid catalyzed hydrolysis through $A-S_E2$ mechanism and specific acid catalyzed hydrolysis through A-2 type(or $A_{AC}2$) mechanism proceeds via conjugate acid($SH^+$) and tetrahedral intermediate(I) below pH 8.0, whereas, above pH 9.0, the general base catalyzed hydrolysis by water molecules(B) through $(E_1)_{anion}$ mechanism proceeds via conjugate base(CB). In the range between $pH\;7.0{\sim}pH\;9.0$, these two reactions occur competitively.

• The Korean Journal of Physiology and Pharmacology
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• v.7 no.5
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• pp.267-273
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• 2003

We have investigated the effect on inducing substate(s) of positively charged residues replaced in position 172 of the second transmembrane domain in murine inward rectifier potassium channels, formed by stable or transient transfection of Kir2.1 gene in MEL or CHO cells. Single channel recordings were obtained from either cell-attached patches or inside-out patches excised into solution containing 10 mM EDTA to rule out the effect of $Mg^{2+}$ on the channel gating. The substate(s) could be recorded with all mutants D172H, D172K and D172R. The unitary current-voltage (I-V) relation was not linear with D172H at $pH_i$ 6.3, whereas the unitary I-V relation was linear at $pH_i$ 8.0. The relative occupancy at $S_{LC}$ was increased from 0.018 at $pH_i$ 8.0 to 0.45 at $pH_i$ 5.5. In H-N dimer, that was increased from 0.016 at $pH_i$ 8.0 to 0.23 at $pH_i$ 5.5. The larger the size of the side chain or $pK_a$ with mutants (D172H, D172K and D172R), the more frequent the transitions between the fully open state and substate within an opening. The conductance of the substate also depended upon the pKa or the size of the side chain. The relative occupancy at substate $S_{LC}$ with monomer D172K (0.50) was less than that in K-H dimer (0.83). However, the relative occupancy at substate with D172R (0.79) was similar to that with R-N dimer (0.82). In the contrary to ROMK1, positive charge as well as negative charge in position 172 can induce the substate rather than block the pore in murine Kir2.1. The single channel properties of the mutant, that is, unitary I-V relation, the voltage dependence of the mean open time and relative occupancy of the substates and the increased latency to the first opening, explain the intrinsic gating observed in whole cell recordings.

• The Korean Journal of Mycology
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• v.45 no.3
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• pp.241-245
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• 2017

Chaga mushroom (Inonotus obliquus), which has invaluable medicinal uses, grows only on living trees. To date, it is still harvested from its natural habitat and is not cultivated artificially. We artificially cultivated chaga mushrooms by inoculating its sawdust spawns on Betula platyphylla var. japonica in 2007, and monitored mushroom growth on the inoculated trees for 9 years. The mushrooms grew less than 1 cm per year, with the largest mushroom growing up to 9 cm in the 9 years of study. There was no difference in the growth (diameter at breast height) of trees with viable and non-viable I. obliquus. In conclusion, artificial cultivation of chaga mushroom was successful. Our findings suggest that selection of large B. platyphylla var. japonica as host tree could lead to better I. obliquus productivity. Further improvements of the method are needed to increase the success rate of I. obliquus inoculation.

• Journal of Radiation Protection and Research
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• v.18 no.1
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• pp.63-70
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• 1993

Double ionization of the K- shell accompanying K- shell electron capture of the 0.035 MeV transition of $^{125}I$ has been studied by counting coincidences between $K_{\alpha}$ hypersatellite X-rays and Ka satellite X-rays emitted when double vacancies are filled. The $^{125}I\;and\;^{125}Te^m$ source materials were used in the measurement. We obtained the coincidence spectrum using two NaI(T1) detectors and a Ge(Li) detector and TAC(Time-to-Amplitude Converter), and then analysed the measured coincidence number $N(K_{\alpha}^{II},\;K_{\alpha}^s)$, the total number $N(K_{\alpha})$ of K X-ray. The probability per K-shell electron capture that a double vacancy is formed, $P_{KK}$ is formed, $P_{KK}$ is found to be $2.15{\times}10^{-4}$.