• Current Photovoltaic Research
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• 제3권4호
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• pp.112-115
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• 2015

In this study, the surface of ITO films was modified using $N_2-O_2$ molecular plasma, and the effects of oxygen concentration in the plasma on the ITO surface properties were investigated. Upon plasma treatment of ITO films, the surface roughness of ITO films seldom changed up to the oxygen concentration in the range of 0% to 40%, while the roughness of the films slightly changed at or above the oxygen concentration of 60%. The contact angle of water droplet on ITO films dramatically changed with varying oxygen concentration in the plasma, and the minimum value was found to be at the oxygen concentration of 20%. The plasma resistance at this condition exhibited a maximum value, and the change of resistance showed an inverse relationship compared to that of contact angle. From these results, it was conjectured that the chemical reactions in the sheath of the molecular plasma dominated more than the physical actions due to energetic ion bombardment, and also the plasma resistance could be used as an indirect indicator to qualitatively diagnosis the state of plasma during the plasma treatment.

• 한국토양비료학회지
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• 제48권5호
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• pp.528-534
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• 2015

Green manure crops have been well recognized as the alternative for chemical fertilizer, especially N fertilizer, because of its positive effect on soil and the environment. Hairy vetch and green barley are the most popular crops for cultivation of rice in paddy field. This study was conducted to evaluate effects of hairy vetch and green barley on soil microbial community and chemical properties during short-term application (three years). For this study, treatments were composed of hairy vetch (Hv), green barley (Gb), hairy vetch + green barley (Hv+Gb), and chemical fertilizer without green manure crops (Con.). Hv+Gb treatment showed the highest microbial biomass among treatments. Principal component analysis (PCA) showed that PC1 (73.0 %) was affected by microbial biomass and PC2 (21.5 %) was affected by fungi, cy19:0/18:$1{\omega}7c$ (stress indicator). Combined treatment with hairy vetch and green barley could be more efficient than green manure crop treatment as well as chemical fertilizer treatment for improvement of soil microorganisms.

• Bulletin of the Korean Chemical Society
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• 제23권1호
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• pp.53-58
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• 2002

A new PVC-membrane electrode for $Ag^+$ ion based on a thia-substituted macrocyclic diamide has been prepared. The electrode exhibited a Nernstian response for $Ag^+$ over a wide concentration range $(1.7{\times}10^{-6}-1.0{\times}10^{-1}M)$. It has a response time <15 s and can be used for at least 3 months without divergence. The proposed membrane sensor revealed good selectivities for $Ag^+$ over a variety of metal ions and can be used in a pH range 3.0-7.5. It has been used successfully for direct determination of $Ag^+$ in different real samples and, as an indicator electrode, in the titration of silver ion.

• Bulletin of the Korean Chemical Society
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• 제23권11호
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• pp.1635-1639
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• 2002

A new solvent polymeric membrane sensor based on tetra(p-chlorophenyl)porphyrinato manganese (III) acetate is described which demonstrates excellent selectivity toward the triiodide ion. The electrode has a linear dynamic range between 1.0 ${\times}$ $10^{-2}$ M and 7.0 ${\times}$$10^{-6}$M with a Nernstian slope of $-59.6{\pm}1$ mV per decade and a detection limit of 5.0 ${\times}$$10^{-6}$M. The proposed sensor revealed good selectivities for triiodide over a wide variety of other anions and could be used in a pH range 2-9. The electrode can be used for at least two months without any considerable divergence in potential. It was applied as indicator electrode in potentiometric titration of the triiodide and As(III) ions.

• Bulletin of the Korean Chemical Society
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• 제27권8호
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• pp.1127-1132
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• 2006

A new salicylate-selective electrode based on the complex N,N'-1,4-butylene bis(3-methyl salicylidene iminato) copper(II) as the membrane carrier was developed. The electrode exhibits a good Nernstian slope of 59.1 ${\pm}$ 1.0 mV/decade and a linear range of $1.0\;{\times}\;10^{-6}$-1.0 M for salicylate. The limit of detection was $5.0\;{\times}\;10^{-7}$ M. It has a fast response time 10 s and can be used for more than three months. The selective coefficients were determined by the fixed interference method (FIM) and could be used in the pH range 4.5-10.5. It was employed as an indicator electrode for direct determination of salicylate in pharmaceutical samples.

• Journal of Korean Vacuum Science & Technology
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• 제2권1호
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• pp.49-54
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• 1998

The effect of deposition paratmeters on the solid-phase crystallization of amorphous silicon films deposited by plasma-enhanced chemical vapor deposition has been investigated by x-ray diffraction. The amorphous silicon films were prepared on Si(100) wafers using SiH4 gas with and without H2 dilution at the substrate temperatures between 12$^{\circ}C$ and 38$0^{\circ}C$. The R. F. powers and the deposition pressures were also varied. After crystallizing at $600^{\circ}C$ for 24h, the films exhibited (111), (220), and (311) x-ray diffraction peaks. The (111) peak intensity increased as the substrate temperature decreased, and the H dilution suppressed the crystallization. Increasing R.F. powers within the limits of etching level and increasing deposition pressures also have enhanced the peak intensity. The peak intensity was closely related to the deposition rate, which may be an indirect indicator of structural disorder in amorphous silicon films. Our results are consistent with the fact that an increase of the structural disorder I amorphous silicon films enhances the grain size in the crystallized films.

• Korean Chemical Engineering Research
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• 제55권4호
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• pp.497-502
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• 2017

Estimation of accident cost is a sound and great safety indicator on determining accurate occupational safety and health prevention. Just like in Korea, Heinrich ratio analysis of (1:4) between direct and indirect costs has been become widely used in safety management because of its simplicity. In this study four major categories of uninsured (indirect) cost items and 18 sub-categories of uninsured (indirect) cost items were identified. To determine and validate the importance and necessity of the results of a literature review an expert or professional surveyed had been analyses using the SPSS 18.0, where in the participants whose expertize is in the field of compensation and safety. Based on the results of survey all participants all uninsured (indirect) cost items classified was important and necessary when accidents occurred. Despite recognition of expert on the classification of uninsured (indirect) cost items, it is quite difficult to make generalization for all kind of costs in occupational accident case due to different nature of business for each industry.

• 대한화학회지
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• 제13권4호
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• pp.313-316
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• 1969

모나자이트 중의 납함량을 신속하고 간편하게 결정하는 방법을 기술하였다. 즉 모나자이트 시료를 황산에 녹여 200ml가 되겠끔 희석하였다. 스트론튬으로 납을 정량적으로 분리한 후 3N 수산화나트륨에 녹였다. 여분의 Zn-EDTA를 가한 다음 남은 아연 이온을 0.01M EDTA표준용액으로 적정하였으며 이때 가리움제 (masking agent)러서 시안화칼륨 및 아세틸 아세톤을 가하였고 pH 5에서 자이렌을 오렌지(Xylenol orange)를 지시약으로 사용하였다.

• Bulletin of the Korean Chemical Society
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• 제29권2호
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• pp.398-404
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• 2008

A new solvent polymeric membrane electrode, based on N,N'-bis(salicylidene)-2,2-dimethylpropane-1,3-diamine Ni(II) as the ionophore, was designed. The oxalate-selective electrode has the dynamic range between 1.0 10-6 M and 1.0 10-1 M with a Nernstian slope of -28.7 1.0 mV per decade. The detection limit was 6.3 10-7 M. The proposed electrode revealed good selectivities for oxalate over a variety of other anions and could be used in a pH range of 2.0-7.8. The electrode can be used for at least two months without any considerable divergence in potential. The designed electrode was applied as an indicator electrode in the potentiometric determination of oxalate in real samples.

• 한국임상수의학회지
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• 제14권2호
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• pp.268-272
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• 1997

This study was performed to estimate the clinical signs and biochemical para meters of indicator on acute hepatic injury induced by the administration of CCl$_{4}$ in rats. Minor behavioral changer brittleness of skin hair and decreased volume of water and food intake were observed in rats after 2 hours of $CCl_{4}$ administration compared to control group. Concentration of serum albumin has shown lower than that of control group. However concentration of total bilirubin has shown higher than that of control group. As times go onto serum LDH activity was significantly increased compared to control Broup. Serum CPK activity hasn't shown change compared to control group. Passive hemagglutination that of afetoprotein was shown negative reaction in all the treatment groups and control group.