• The Korean Journal of Pesticide Science
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• v.6 no.3
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• pp.175-182
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• 2002

This experiment was conducted to investigate the effects of acid rain in spraying copper hydroxide 77% wettable power(WP) on leaf surface morphology and crop injury of the garlic(Allium sativum L.). Leaf chlorosis, hooked leaves, wrinkled epidermal cells and increased stomata open of garlic were induced by foliar application of simulated acid rain(SAR). It was become to be severe in application of copper hydroxide solution after application of SAR, but those yield of garlic was not significantly different from the untreated control. Leaf chlorosis was sharply increased above 100 ppm of copper ions. Amount of solved copper ions in copper hydroxide solution was remarkably increased below pH 5.5 and the residue in garlic leaves was significantly increased by application of copper hydroxide solution after spraying SAR compared with application of copper hydroxide solution only. When calcium carbonate was applied together with copper hydroxide leaf chlorosis was less than copper hydroxide only.

• The Korean Journal of Zoology
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• v.33 no.1
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• pp.108-118
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• 1990

Fibronectin is a glycoprotein found in the extracellular matrix as well as in the serum, and has been known to exert pronouned effed on the myoblast fusion. Our previous studies have suggested that the decrease of fibronectin levels during myogenesis is due to the decreased availability of the receptor for the 28 kDa fragrnent of fibronetin. In the fusion-blocked myoblasts by EGTA, the levels of fibronetin and binding of 28 kDa fragment decreased but far less than the control level. In contrast, the levels of fibronetin and binding of 28 kDa fragment decreased to the control level in the myoblast released from the fusion block. On this account, we suggest that the decrease of fibronetin levels during myoblast fusion is closely associated with the loss or alteration of the receptor for 28 kDa fragment. Mild trypsin treatment decreased the binding of the 28 kDa fragment to the myoblasts significandy. Similarly, the presence of gangliosides in the binding media decreased the binding of the 28 kDa fragment in a dose-dependent manner. Furthermore, gel overlay of 125 I-28 kDa fragment on the SDS-PAGE of the myoblast homogenates revealed that the 28 kDa fragment bound to a 43 kDa protein and to gangliosides as well. These results suggest that myoblast fusion is correlated with decrease of the receptor for the 28 kDa fragment and that the receptor might be a glycoprotein that contains glyco-conjugate found in gangliosides.

• Korean Journal of Food Science and Technology
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• v.20 no.1
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• pp.52-58
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• 1988

This study has investigated the effect of Ganoderma lucidum water soluble extract on higher alcohol production of Saccharomyces cerevisiae. S. cerevisiae was inoculated in malt wort media which were added 0, 0.01, 0.1, 0.5 or 1.0% extracts of G. lucidum and fermented at $15^{\circ}C$ for 120 hours respectively. Some results about cell growth, changes of pH and sugarity and alcohol composition during fermentation are as follows; The cell growth of S. cerevisiae was remarkablely increased as G. lucidum extract was added into each step. It was increased to 1.2, 1.5, 1.9 times on added group of 0.1%, 0.5%, 1.0% G. lucidum extract than control group after the fermentation of 120 hours. Content of sugar was systematically low on step of addition of G. lucidum extract after the fermentation of 120 hours but pH was systematically high. The more the quantity of G. lucidum extract was added, the more total alcohol quantity were produced during fermentation. Especially higher alcohol content was more increased about 1.8 times on 1.0% group (219.9 ppm w/v) than on control group (117.26 ppm w/v) after the fermentation of 120 hours.

• Korean Chemical Engineering Research
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• v.58 no.3
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• pp.466-473
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• 2020

Fabric current collector can be a promising electrode material for Capacitive Deionization (CDI) system that can achieve energy-efficient desalination of water. The one of the most attractive feature of the fabric current collector is its high tensile strength, which can be an alternative to the low mechanical strength of the graphite foil electrode. Another advantage is that the textile properties can easily make shapes by simple cutting, and the porosity and inter-fiber space which can assist facile flow of the aqueous medium. The fibers used in this study were made of woven structures using a spinning yarn using conductive LM fiber and carbon fiber, with tensile strength of 319 MPa, about 60 times stronger than graphite foil. The results were analyzed by measuring the salt removal efficiency by changing the viscosity of electrode slurry, adsorption voltage, flow rate of the aqueous medium, and concentration of the aqueous medium. Under the conditions of NaCl 200 mg/L, 20ml/min and adsorption voltage 1.5 V, salt removal efficiency of 43.9% in unit cells and 59.8% in modules stacked with 100 cells were shown, respectively. In unit cells, salt removal efficiency increases as the adsorption voltage increase to 1.3, 1.4 and 1.5 V. However, increasing to 1.6 and 1.7 V reduced salt removal efficiency. However, the 100-cell-stacked module showed a moderate increase in salt removal efficiency even at voltages above 1.5 V. The salt removal rate decreased when the flow rate of the feed was increased, and the salt removal rate decreased when the concentration of the feed was increased. This work shows that fabric current collector can be an alternative of a graphite foil.

• 한국노년학
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• v.29 no.1
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• pp.177-194
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• 2009

Korea government has launched long-term care insurance from 2008. However, one of the most important issues, whether or not providing cash benefit, is still unresolved. In this paper, in order to provide policy guidelines for the long-term care insurance, I attempt to estimate the Willingness-To-Accept (WTA) of the cash subsidy for informal care by using Double Bounded Dichotomous Choice method, a branch of Contingent Valuation Method (CVM). In doing so, I also estimated the determinants of the preference for cash benefit. Data were obtained from face-to-face survey interviews with 300 informal care-givers at three major general hospitals in Seoul, Korea. The questionnaire was constructed with two scenarios (mild/severe symptom). The results from logistic regression analyses and the estimation of WTA indicate that informal care-givers are willing to accept the cash benefit as low as 628 thousands won for mild fragile elderly and 1,072 thousands won for severe fragile elderly. The strength of this paper is that I estimated the WTA of the cash benefit by reflecting the changes in preferences of informal care-givers. The analytic results from the this paper suggest that the cash benefit in long-term care insurance is indispensible in achieving the goal of the long-term care system.

• Journal of the Korean Electrochemical Society
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• v.6 no.2
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• pp.153-157
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• 2003

A hybrid electrochemical capacitor having both characteristics of electric double layer capacitance and pseudo-capacitance was studied throughout cell tests. Asymmetric electrodes with $Ni(OH)_2/activated$ carbon based positive electrode and activated carbon based negative electrode were used in preparing test cells of $5\times5cm^2$. Cyclic voltammetry measurements and impedance measurements were conducted to understand electrochemical behavior of each electrode. To find an optimal mass ratio of negative to positive electrode, charge-discharge cycle tests were also performed.

• Sijohaknonchong
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• v.23
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• pp.71-105
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• 2005

Toson-Shibigok(Twelve Songs of Toson) which T'oegye, Yi Hwang, composed has received a lot of attention in terms of its educational implications. These implications have become the essential part of Gojeon Sigas(classic songs and poems), and solid evidence has also been accumulated in the literature. Therefore, the purposes of this study are twofold, that is 1) to explore the impact of T'oegye's fundamental structure of the first education at that time and 2) describe how these educational attitudes will eventually yield meta- educational values. What T'oegye meant by fundamental structure of the first education was that Sijos originated from his own experience should be the vital part of teaching method. One can say that T'oegye's teaching method is more integrative than that of modern literature education in that it includes songs. Not only using his own teaching method, but T'oegye tried to demonstrate his own literary structure to his colleagues and the future generations. In the end, Meta-Education which comprises the heart of recent educational theories well reflects Toegye's theoretical propositions. Rather than giving practical knowledge, his method offers the paradigms of thought patterns and shows the learners' attitudes in approaching the truth. Moreover, T'oegye's teaching method has become a good example to the future generations as well as his contemporary followers. In sum, although a lot of years have passed since he died, T'oegye's Sijo works and life still have invaluable impact on the field of education.

• Journal of the Korean institute of surface engineering
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• v.41 no.5
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• pp.240-244
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• 2008

Composite plating is a method of co-deposition of plating layer with metallic and/or non-metallic particles to improve the plating layer properties such as high corrosion resistance and photolysis of organic compounds. The properties of nickel-ceramic composite plating are significantly depend on the surface characteristics of co-deposited particles as well as the quantity in electrolyte. In this study, Ni-$TiO_2$ composite coating layer was produced by electrodeposition technique from non-aqueous eletrolyte and its surface characteristics as well as photolytic properties were investigated. The amounts of immobilized $TiO_2$ particles increased with increasing the initial $TiO_2$ particles contents in the bath. Samples electroplated with the current density of $0.5\;A/dm^2$ showed the significantly improved homogeneous $TiO_2$ particles distribution. The corrosion resistance of Ni-$TiO_2$ composite coating layer also improved with increaing the amounts of $TiO_2$ particles. Etched sample showed about 10% increased photolytic rate of organic matter compare to that of the non-etched.

• Journal of the Korean Chemical Society
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• v.64 no.1
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• pp.30-37
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• 2020

The purpose of this study was to identify the problems faced by students in sub-microscopic representation of acid-base reactions. Herein, we selected 30 students of 12^th grade science classes, who had studied various acid-base models. In order to investigate the sub-microscopic representation ability of the students, we developed nine items related to various contexts, such as one type of solute and solvent, two types of solutes and solvent, cases with water as solvent or with nonaqueous solvents. For all items, we consistently observed lack of concept of chemical change. In context of aqueous and nonaqueous solutions, the frequency of lack of concept of chemical bonding was high if ammonia was the solute or solvent. Moreover, the frequency of lack of concept related to the degree of electrolytic dissociation was high. Therefore, chemistry teachers should understand that students' ability to sub-microscopic representation of acid-base reactions can be enhanced by analyzing the difficulties faced by the students in solving diverse acid-base problems.

• Journal of the Korean Electrochemical Society
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• v.10 no.2
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• pp.126-131
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• 2007

The durability problem of Prussian blue in non-aqueous $Li_+$-based electrolytes has been due to the degradation of the Prussian blue electrode matrix during the insertion/extraction processes by $Li_+$. In this work, we designed and synthesised the Prussian blue without reducing the electrochromic performance in non-aqueous $Li_+$-based electrolytes. Prussian blue was electrodeposited on a glass which has ITO coating, and the coating solution is a mixture solution of $FeCl_3\;and\;K_3Fe(CN)_6$ with deionized water added HCl, KCl, and LiCl, respectively. The durability of Prussian blue was evaluated by an in-situ transmittance measurement during a continuous and pulse potential cycling test, and measured by electroactive layer thickness due to evaluating the degradation.