• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.4 no.3
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• pp.195-200
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• 2000

The kinetics of the reaction between carbonyl sulfide and aqueous monoethanolamine were studied over a range of temperature (298-348 K) and amine concentrations using a wetted-sphere absorber. The key physicochemical properties used to interpret the data included the solubility and diffusivity of the COS in the aqueous amine solution. The experimental data were interpreted using a zwitterion mechanism, which produced an Arrhenius plot with third-order kinetic rate constants. The fit of these data was $K_3$=$1.32\times10(sup)10exp(\frac{-6136}{T}}$

• Journal of the Korean Applied Science and Technology
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• v.26 no.3
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• pp.362-369
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• 2009

Esterification reaction between succinic acid and 1,4-butanediol was kinetically investigated in the presence of monobutyl tinoxide catalysts at $150{\sim}190^{\circ}C$. The reaction rates measured by the amount of distilled water from the reaction vessel. The esterification reaction was carried out under the first order conditions with respect to the concentration of reactants, respectively. The overall reaction order was 2nd. The linear relationship was shown between apparent reaction rate constant and reciprocal absolute temperature. By the Arrhenius plot the activation energy have been calculated as 87.567 kJ/mol under monobutyl tinoxide catalyst and also apparent reaction rate constant, k' was found to obey first kinetics with respect to the concentration of catalyst.

• Journal of Korean Society for Atmospheric Environment
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• v.4 no.1
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• pp.13-22
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• 1988

Interactions between hydrodesulfurization of thiophene and hydrodenitrogenation of pyridine and the kinetic analysis were studied over $Ni-W/\gamma-Al_2O_3$ catalysts and this study was made at temperatures ranging from 473-673 K and at total pressures ranging from 10-25 $\times 10^5$ Pa. Hydrodesulfurization of thiophene was inhibited by presence of pyridine at all temperatures studied, and the rate of pyridine hydrodenitrogenation was slower than that of thiophene hydrodesulfurization in the operating conditions. Pyridine hydrodenitrogenation was also inhibited by the presence of thiophene at low temperatures but was enhanced by the thiophene at temperatures higher than 613K. Thiophene reaction rate was determined by multiple linear regression analysis using Langmuir-Hinshelwood-Hougen-Watson model and the result was given to be $r = kP_T^p_H/(1+K_Tp_T+K_Pp_P)^2$. At each temperature, reaction rate constants and absorption equilibrium equilibrium constants were determined and the activation energy was 12.98 kcal/gmol from Arrhenius plot.

• Journal of the Korean institute of surface engineering
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• v.21 no.4
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• pp.160-167
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• 1988

Electrochemical behaviors od chromium electrodeposition from 0.05M chromium (III) sulface complexes in aqueous solutions using sodium formate-glycine mixtures as a complexing agent were studied. In the cathodic current-potential cures, it is found that the intial limiting current of Cr(III) is proportional to square root of scan rate and activiation energy from Arrhenius plot is s obtained 3.05Kcal/mol. From this results, the reaction is considered, Cr3++e longrightarrow Cr2+, which is controlled diffusion of Cr (III). It is also found that the chromium is deposited when the potential reaches to hydrogen evolution potential. Effects of NaSCN as a catalyser in the electrolyte were investigated NCS- anion seems to react strongly by specific absorption at the inner HelmholtZ layer, so that, it is considered to suppress the electrodeposition reaction reaction for chromjum, and also it is considered multipe-bridge such as Cr(III)-NCS---M(M;cathode).

• Korean Journal of Microbiology
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• v.21 no.1
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• pp.27-35
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• 1983

The stoichiometry between the consumption of CO and $O_2$ and the production of $CO_2(2CO+O_2{\rightarrow}2CO_2)$) showed that Pseudomonas carboxydohydrogena grows as a typical aerobic CO oxidizer with CO. The optimal concentration of CO for growth was found to be 30% in gas mixture with air. The initial buffer concentration of the culture medium did not affect the growth of this bacterium. P. carboxydohydrogena is an obligate aerobe and dose not use nitrate as a terminal electron acceptor. The CO dehydrogenase is an inducible and soluble enzyme. The reaction rate and stability were maximal at pH7.5, and the Arrhenius plot revealed an activation energy of 37.7kJ/mol (9.0 Kcal/mol). The crude enzyme used methylene blue, thionin, and toluylene blue as electron acceptors for the oxidation of CO to $Co_2$ under anaerobic conditions. It was found that water must be the source of the second oxygen atom for CO oxidation.

• The Korean Journal of Food And Nutrition
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• v.4 no.1
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• pp.1-8
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• 1991

This study was attempted to establish the basic data for effective utilization of the dried radish and sweet potato. The rehydration characteristic was carried out from these dried root vegetables in various conditions. The following results were obtained. The rehydration value was increased in glycine solution, whereas It decreased in lactic acid solution. Also the vacuum freezing was higher than that in hot air drying, and it was higher the slow freezing than in the quick freezing. The rehydration rate and the rehydration surface area curve were composed of three stages, and these stages were corresponded to each other. At the range of initial immersion to 2min., the largest rehydration rate was showed. The activation energy obtained from the Arrhenius plot of the rehydration rate constant(K) were 3. Bx103ca11g mol and 3.7$\times$103cal/g mol for dried radish and sweet potato, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05b
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• pp.98-101
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• 2005

BSCCO thin films fabricated by using the evaporation method. As a result, although the composition of Bi2212 was set up, the phase of Bi2201, Bi2212 and Bi2223 was formed. The formation area of these stable phases is indicated as inclined line in the direction of the right lower end from the Arrhenius plot of the substrate temperature-oxidation gas pressure, and are distributed in very small area. The activation energy for the phase transformation from the Bi2201 to the Bi2212 is estimated in terms of the Avrami equation.

• Journal of the Korean Ceramic Society
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• v.31 no.3
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• pp.241-248
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• 1994

The ionic conductivity in glassy systems were calculated as functions of temperature and ion concentration using Monte-Carol method considering interaction between neighbouring ion-site occupancies, {{{{ rho }}'s. Also the vacancy availability factor, V, the effective jump frequency factor, W, and the charge correlation factor, fc, have been investigated. The Arrhenius plot could be obtained from the ln {{{{ sigma }}T vs. 1/T* plots and was in exellent agreement with the experimental observations. The effects of the various types of potential well on the ionic conductivity have been considered. The activation energy Eg for ion motion in the glass was 1.3│ε│from the ln {{{{ sigma }}T vs. 1/T* plots.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1010-1015
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• 2009

Rail-pad is an important and readily replaceable component of a railway track, as it is the elastic layer between the rail and the sleeper. Characteristics and useful lifetime prediction of rail-pad was very important in design procedure to assure the safety and reliability. In order to investigate the useful lifetime, the accelerate test were carried out. Accelerated test results changes as the threshold are used for assessment of the useful life and time to threshold value were plotted against reciprocal of absolute temperature to give the Arrhenius plot. By using the acceleration test, several useful lifetime prediction for rail-pads were proposed.

• Journal of Ginseng Research
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• v.10 no.2
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• pp.180-186
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• 1986

Photosynthesis and respiration of leaf and root of field grown Panax ginseng were investigated according to aerial part sensecence. No apparent photosynthesis activity was detected in senescenced leaf(less than 0.7mg total chlorophyll/g FW) and leaf dark respiration was consistent relation with senescence. Leaf respiratory Q$_{10}$ consistently increased with senscence. Root respiration and Q$_{10}$ tended to decrease with aerial part senescence only in the range of optimum temperature of leaf growth. Apparent photosynthesis or respiration of leaf was negatively or positively correlated, respectively with the increase of air temperature. Root respiration with temperature was well accordance with Arrhenius plot which was not consistent with aerial part senescence. Accelerated senescence may be recommendable for better root yield unless any reserve in stem or leaves contributes to root through translocation.