• Journal of Microbiology and Biotechnology
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• v.13 no.2
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• pp.191-195
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• 2003

The in vitro glycosylation of pentapeptide (Arg-Lys-Asp-Val-Tyr; RKDVY) and RNase A was carried out using PNGase F (peptide-N-glycosidase F), and the results were analyzed using MALDI-TOF-MS. Aminated N,N-diretyl chitobiose was used as the sugar in the glycosylation reaction, and the amination yield of N,N'-diacetyl chitobiose was about $60\%$. To reduce the water activity and shift the reaction equilibrium to a reverse reaction, 1,4-dioxane or ethylene glycol was used as the organic solvent in the enzymatic glycosylation. A certain extent of nonenzymatic glycosylaton, known as the Maillard reaction, was also observed, which occurs on an arginine or lysine residue when the length of tie sugar residue is one or two. However, the extent of glycosylation was much higher in the enzymatic reaction, indicating that PNGase F can be effectively used to produce glycopeptides and glycoproteins in vitro.

• The Journal of Asian Finance, Economics and Business
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• v.4 no.1
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• pp.19-23
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• 2017

Based on a simultaneous-equation model consisting of aggregate demand and short-run aggregate supply, this paper estimates a reduced-form equation specifying that the equilibrium real GDP is a function of the real effective exchange rate, the government deficit as a percent of GDP, the real interest rate, foreign income, labor productivity, the real oil price, the expected inflation rate, and the interactive and intercept binary variables accounting for a potential change in the slope of the real effective exchange rate and shift in the intercept. Applying the exponential GARCH technique, it finds that aggregate output in Australia has a positive relationship with the real effective exchange rate during 2003.Q3 - 2013.Q2, the government deficit as a percent of GDP, U.S. real GDP, labor productivity and the real oil price and a negative relationship with the real effective exchange rate during 2013.Q3 - 2016.Q1, the real lending rate and the expected inflation rate. These results suggest that real appreciation was expansionary before 2013.Q3 whereas real depreciation was expansionary after 2013.Q2 and that more government deficit as a percent of GDP would be helpful to stimulate the economy. Hence, the impact of real appreciation or real depreciation on real GDP may change overtime.

• Applied Chemistry for Engineering
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• v.4 no.2
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• pp.409-415
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• 1993

A potential function is applied to a hydrogen bonded system such as O-H---O and is slightly modified to provide a good understanding of a range of data. The use of this model requires a knowledge of terms describing the Van der Waals repulsion and the electrostatic interaction and the determination of these terms form the equilibrium conditions is described. Using this simple model, it will be shown that the relationship between the frequency shift and enthalpy of hydrogen bond formation is predicted to be linear and this is in reasonable agreement with experimental results in the literature.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.1
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• pp.60-68
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• 2009

The steam reformer for hydrogen production from methane is studied by a numerical method. Langmuir- Hinshelwood model is incorporated for catalytic surface reactions, and the pseudo-homogeneous model is used to take into account local equilibrium phenomena between a catalyst and bulk gas. Dominant chemical reactions are Steam Reforming (SR) reaction, Water-Gas Shift (WGS) reaction, and Direct Steam Reforming (DSR) reaction. The numerical results are validated with experimental results at the same operating conditions. Using the validated code, parametric study has been numerically performed in view of the steam reformer performance. As increasing a wall temperature, the fuel conversion increases due to the high heat transfer rate. When Steam to Carbon Ratio (SCR) increases, the concentration of carbon monoxide decreases since WGS reaction becomes more active. When increasing Gas Hourly Space Velocity (GHSV), the fuel conversion decreases due to the heat transfer limitation and the low residence time. The reactor shape effects are also investigated. The length and radius of cylindrical reactors are changed at the same catalyst volume. The longer steam reformer is, the better steam reformer performs. However, system energy efficiency decreases due to the large pressure drop.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1378-1382
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• 2013

We have investigated the complex forming behavior of cucurbit[6]urils(CB6) and cucurbit[7]urils(CB7) with 7-diethylamino-4-methylcoumarin(C460) in water. The electronic absorption maximum of C460 shows bathochromic shift with the addition of CB7 and fluorescence intensity is greatly increased, while CB6 has no noticeable effects on the spectroscopic properties of C460. It is noted that CB7 interacts more strongly with C460 than CB6 does. Fluorescence lifetime also significantly increased for the CB7 complex, which is attributed to reduced polarity surrounding C460 and/or C460 being in a restricted environment. The stoichiometry for the complex formation determined from the fluorescence titration measurement indicates that 2:1 complex in which two CB7 molecules bind to C460 is formed. Thus, two step equilibrium processes are suggested for the complex formation and the binding constants are estimated. The semi-empirical electronic structures calculations indicate that C460 is not included in the CB7 cavity but interacts noncovalently with the portal carbonyls of CB7.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.11
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• pp.859-866
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• 2006

This paper presents the vapor-liquid equilibrium (VLE) data measured for carbon dioxide and propane mixtures. Their mixtures were considered as promising alternative refrigerants due to good thermophysical properties and negligible environmental impact. The isothermal VLE data were measured at eight temperatures ranging from 253.15 to 323.15 K in the circulation type equipment with a view cell. The binary system was found to be a zeotropic mixture in the tested temperature range and could be correlated with sufficient accuracy by using the Peng-Robinson equation of state (PR EoS) with the van der Waals one fluid mixing rule. A comparison with published experimental VLE data has been carried out by means of the PR equation of state. In addition, the phase behaviors of carbon dioxide and propane mixtures were analyzed based on the measured VLE data.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.3
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• pp.155-163
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• 2021

The study aims to investigate the effect on Philippine occupational choice of House Bill No.7787, also known as the National Wage Law, which was filled by the Philippine Congress that mandates the implementation of an across the board minimum daily wage of Php750.00 to all workers in the Philippines. This study had used the Computable General Equilibrium-Top-Down Behavioral Microsimulation approach to determine the effect of National Wage Law on occupational choice. The results of the study revealed that the implementation of said National Wage Law would affect the distribution of labor force across occupational classification such as wage workers, entrepreneurial farming activities workers, and entrepreneurial non-farming activities workers. This has resulted from a higher utility that will be derived from the wage working sector once the National Wage Law will be implemented. Further, among regions in the Philippines, the Calabarzon, National Capital Region, and Central Luzon had recorded the highest number of workers who prefer the wage income sector. The findings of the study also suggest that the Philippine agricultural sector will be greatly affected by the National Wage Law due to the preference of workers to shift from the entrepreneurial farming sector to belong to the wage sector.

• Journal of the Korean Electrochemical Society
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• v.4 no.1
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• pp.14-20
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• 2001

The Langmuir adsorption isotherms of the under-potentially deposited hydrogen (UPD H) and the over-potentially deposited hydrogen (OPD H) at the single crystal Pt(100)/0.5 M $H_2SO_4$ and 0.5 M LiOH aqueous electrolyte interfaces have been studied using the phase-shift method. The phase-shift profile $({-\varphi}\;vs.\;E)$ for the optimum intermediate frequency can be used as a useful method to estimate the Langmuir adsorption isotherm $(\theta\;vs.\;E)$ at the interfaces. The equilibrium constant (K) for the OPD H and the standard free energy $({\Delta}G_{ads})$ of the OPD H at the Pt(100)/0.5M $H_2SO_4$ aqueous electrolyte interface are $1.5\times10^{-4}$ and 21.8 kJ/mol, respectively. At the Pt(100)/0.5 LiOH aqueous electrolyte interface, K transits from 1.9(UPD H) to $6.8\times10^{-6}$(OPD H) depending on the cathode potential (E) and vice versa. Similarly, ${\Delta}G_{ads}$ transits -1.6 kJ/mol (UPD H) to 29.5 kJ/mol (OPD H) depending on E and vice versa. The transition of K and ${\Delta}G_{ads}$ is attributed to the two distinct adsorption sites of the UPD H and OPD H on the Pt(100) surface. The UPD H and the OPD H at the Pt(100) interfaces are the independent processes depending on the H adsorption sites rather than the sequential processes for the cathodic $H_2$ evolution reactions.

• Journal of the Korean Electrochemical Society
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• v.2 no.3
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• pp.144-149
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• 1999

The two distinct adsorption sites and transition between the under and over-potentially deposited hydrogen (UPD H and OPD H) on the polycrystalline iridium (poly-Ir) surface in the 0.2 M LiOH electrolyte have been studied using the phase-shift method. At the forward and backward scans, the UPD H peak occurs on the cyclic voltam-mogram. The transition region on the phase-shift profile or the Langmuir adsorption isotherm occurs at ca. -0.80 to -0.95 V vs. SCE. At the transition region (-0.80 to -0.95 V vs. SCE), the equilibrium constant (K) for H adsorption transits from $7.9\times10^{-2}\;to\;1.5\times10^{-4}$ and vice versa. Similarly, the standard free energy $({\Delta}G_{ads})$ of H adsorption transits from 6.3 to 21.8kJ/mol and vice versa. The UPD H and OPD H on the poly-Ir surface act as two distinguishable electroadsorbed H species. Both the UPD H peak and the transition region are attributed to the two distinct adsorption sites of the UPD H and OPD H on the poly-Ir surface.

• Journal of the Korean Electrochemical Society
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• v.2 no.4
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• pp.213-217
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• 1999

The electrochemical characteristics of two distinct adsorption sites of H at the polycrystalline Pt/0.2 M LiOH aqueous electrolyte interface have been studied using the phase-shift method. At the forward and backward scans, the under-potentially deposited H (WD H) peak occurs on the cyclic voltammogram. The transition region on the phase-shift profile or the Langmuir adsorption isotherm occurs at ca. -0.66 to -0.96 V vs. SCE. At the transition region (ca. -0.66 to -0.96 V vs. SCE), the equilibrium constant (K) for H adsorption transits from 18.5 to $4.0\times10^{-5}$ and vice versa. Similarly, the standard free energy $({\Delta}G_{ads})$ of H adsorption transits from -7.2 to 25.1kJ/mol and vice versa. The under and over-potentially deposited H (UPD H and OPD H) on the poly-Pt surface act as two distinguishable electroadsorbed H species. An exothermic reaction occurs at the UPD H range. Both the UPD H peak and the transition region are attributed to the two distinct adsorption sites of the UPD H and OPD H on the poly-Pt surface.