• Journal of Integrative Natural Science
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• v.10 no.3
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• pp.171-174
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• 2017

Non-hydrolyzable fluorinated organosilicon compounds as an eletrolyte for the application of lithium-ion batteries (LIB) are synthesized. New synthetic method for the perfluorinated organosilicon compound containing spacer such as ethyl and propyl group with cyano moiety instead of ethylene glycol to prevent hydrolysis and to promote conductivity are developed in one pot reaction with moderately high yield. Air-sensitive boron trifluoride etherate is no longer required in this reaction. The products are characterized by spectroscopic analysis.

• Bulletin of the Korean Chemical Society
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• v.13 no.5
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• pp.538-541
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• 1992

An approximate scheme for evaluating total reaction probability is proposed. Semiclassical boundary conditions are imposed well before the asymptotic region in the reactant and product channels to calculate the Green's function and its derivatives. Propagations are confined to a limited regime near the activated complex. Calculations are made for one dimensional Eckart barrier model of H + $H_2$ reaction. Implications of the procedure in multi-dimensional systems are discussed.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.186.4-187
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• 2003

Acanthoside-D, one of major components of Acanthopanacis Cortex, is known as a ginseng-like substance. it has been known to possess diverse biological effects. Acanthoside-D has a furofuran lignan structure and the synthesis of which poses interesting and often unsolved proplems of stereocontrol. Although a few interesting syntheses providing this natural product have been reported, an intermolecular McMurry coupling - intramolecular Mitsunobu cyclization route has not yet been explored. We report here a short and efficient synthetic pathway to the total synthesis of Acanthoside-D from aryl aldehydes and methyl acrylates via Baylis-Hillman reaction, intermolecular McMurry coupling and intramolecular Mitsunobu cyclization as key reaction.

• Korean Journal of Applied Biomechanics
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• v.26 no.2
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• pp.143-151
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• 2016

Objective: The purpose of this study was to investigate the effect of fatigue induction on ground reaction force (GRF) components, postural stability, and vertical jump performance in Taekwondo athletes. Method: Ten Taekwondo athletes (5 men, 5 women; mean age, $22.30{\pm}2.62years$; mean height, $174.21{\pm}9.20cm$; mean body weight, $67.28{\pm}12.56kg$) participated in this study. Fatigue was induced by a short period of strenuous exercise performed on a motorized treadmill. The analyzed variables included vertical jump performance, static stability (mediolateral [ML], center of pressure [COP], anteroposterior [AP] COP, ${\Delta}COPx$, ${\Delta}COPy$, and COP area), postural stability index values (ML stability index [MLSI], AP stability index [APSI], vertical stability index [VSI], dynamic postural stability index [DPSI]), and GRF components (ML force, AP force, peak vertical force [PVF], and loading rate). To analyze the variables measured in this study, PASW version 22.0 was used to calculate the mean and standard deviation, while a paired t-test was used to evaluate the pre- versus post-fatigue results. Pearson's correlation coefficients among variables were also analyzed. The statistical significance level was set at ${\alpha}$ = .05. Results: Vertical jump performance decreased significantly after the induction of fatigue, while AP COP, ${\Delta}COPx$, COP area, APSI, VSI, and DPSI increased significantly. PVF and loading rate increased significantly after the induction of fatigue, while the postural stability variables (AP COP, ${\Delta}COPy$, COP area, APSI, VSI, DPSI) were similarly correlated with GRF components (PVF, loading rate) after fatigue was achieved (r = .600, $R^2$ = 37%). Conclusion: These results suggest that the induction of fatigue can decrease postural stability and exercise performance of Taekwondo athletes during training and competition sessions.

• Journal of the Korean Chemical Society
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• v.28 no.2
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• pp.95-101
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• 1984

Aquation reaction kinetics of $[Cr(en)_2Cl_2]^+$complex was carried by the electric conductivity method. Its temperature range was $15^{\circ}C$ to $30^{\circ}C$ and pressure was varied up to 2,000 bars. The reaction rate was increased with increasing temperature, but was reversed to increasing pressure. The activation volume(${\Delta}V^{\neq}$) was increased with increasing temperature and decreased with increasing pressure. At $25^{\circ}C$ and 1 bar it was fairly small positive value, $1.82cm^2/mole$. Activation entropy change(${\Delta}S^{\neq}$) $was calculated as small negative value,-9.019 eu, at $25^{\circ}C$ and 1bar. Referring to the thermodynamic parameters, it was estimated that aquation reaction was proceeded by the interchange-dissociation(Id) mechanism.

• Journal of the Korean Society of Radiology
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• v.10 no.5
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• pp.337-341
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• 2016

We measured the neutron capture cross-section of natural Sm(n,${\gamma}$) reaction in the energy regions from 0.003 to 10 eV. The 46-MeV electron linear accelerator of Research Reactor Institute, Kyoto University was used for generating a continuous neutron source. The neutron time-of-flight method was adopted for energy measurement. An assembly of BGO($Bi_4Ge_3O_{12}$) scintillators composed of 12 pieces of BGO crystals measured prompt gamma rays from Sm(n,${\gamma}$) reaction. The BGO assembly was located at a distance of $12.7{\pm}0.02m$ from the neutron source. In order to determine the neutron flux impinging on the Sm, the $^{10}B(n,{\alpha}{\gamma})^7Li$ standard cross-section were used. Natural Sm(n,${\gamma}$) reaction measurement result of the neutron capture cross-section was compared with the results of evaluation of the BROND-2.2 and the previous experimental data of J. C. Chou and V. N. Kononov.

• Journal of the Korean Chemical Society
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• v.22 no.6
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• pp.370-379
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• 1978

The specific rate constants for the oxidation reactions of carbon monoxide on a unit catalytic surface area were measured. The catalysts used were NiO made from $Ni(NO_3)_2,\;and\;Ni(OH)_2$, and Mn$O_2$ made from Mn$(NO_3)_2$. At low pressure the reaction rate was found to be of second order and the activation energies were 12 kcal/mole (on NiO made from Ni$(NO_3)_2$, 17 kcal/mole (on NiO made from Ni$(OH)_2)$) and 18 kcal/mole (on Mn$O_2$). Plausible reaction mechanisms were proposed from the experimentally determined reaction orders.

• Journal of the Mineralogical Society of Korea
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• v.21 no.4
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• pp.415-423
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• 2008

Earth outer core is composed of iron mainly with some diluent elements, which account for the observed ca. 10% density deficit compared to the pure iron. Among candidates as the light diluents, hydrogen and oxygen were selected, and the thermodynamic stability of the following reaction was calculated; hematite + hydrogen $\to$ goethite + iron. At ambient conditions, Gibb's free energy of this reaction is 12.62 kJ/mol. On increasing pressure at room temperature, it decreases to zero at 0.068 GPa. This energy decreases at constant rate down to 200 GPa, which shows -208.26 kJ/mol at that pressure. From these results, this chemical reaction prefers the reduction environment forming the iron element and iron oxyhydroxide, so possible presence of iron oxyhydroxide with iron at proto-core can not be ruled out.

• Journal of the Korean Chemical Society
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• v.32 no.4
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• pp.301-310
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• 1988

Reaction rates for mononuclear heterocyclic rearrangement of N-(5-phenyl-1,2,4-oxadiazol-3-yl)-N'-arylformamidines into 3-acylamino-1-aryl-1,2,4-triazoles were determined spectrophotometrically in dioxane/water (50 : 50, v/v). There are two different reaction paths according to pH. One is pH-independent path, the other is pH-dependent one. In pH-independent path, the result of substituent effect by IYT equation show that N-H bond breaking as well as new N-N bond formation controls the reaction rate. In pH-dependent path, concave-upward Hammett plot was observed. It can be concluded that new N-N bond formation is more advanced than N-H bond breaking in transition state for electron-donating substituents, but N-H bond breaking is more advanced than new N-N bond formation for electron-withdrawing substituents.

• Molecules and Cells
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• v.23 no.3
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• pp.287-303
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• 2007

Expressed sequence tags (ESTs) and differentially expressed cDNAs from the self-fertilizing fish, Kryptolebias marmoratus were mined to develop alternative biomarkers for endocrine-disrupting chemicals (EDCs). 1,577 K. marmoratus cDNA clones were randomly sequenced from the 5'-end. These clones corresponded to 1,518 and 1,519 genes in medaka dbEST and zebrafish dbEST, respectively. Of the matched genes, 197 and 115 genes obtained Unigene IDs in medaka dbEST and zebrafish dbEST, respectively. Many of the annotated genes are potential biomarkers for environmental stresses. In a differential display reverse transcriptase-polymerase chain reaction (DD RT-PCR) study, 56 differential expressed genes were obtained from fish liver exposed to bisphenol A. Of these, 16 genes were identified after BLAST search to GenBank, and the annotated genes were mainly involved in catalytic activity and binding. The expression patterns of these 16 genes were validated by real-time RT-PCR of liver tissue from fish exposed to bisphenol A. Our findings suggest that expression of these 16 genes is modulated by endocrine disrupting chemicals, and therefore that they are potential biomarkers for environmental stress including EDCs exposure.