• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.11a
• /
• pp.57-58
• /
• 2006

In MIM (metal insulator metal) capacitor, Ru (ruthenium) has been suggested as new bottom electrode due to its excellent electrical performance, a low leakage of current and compatibility to the high dielectric constant materials. In this case of Ru bottom electrode, CMP (chemical mechanical planarization) process was needed m order to planarize and isolate the bottom electrode. In this study, the effect of chemical A on polishing and etching behavior was investigated as functions of chemical A concentration, abrasive particle and pressure. Chemical A was used as oxidant and etchant. The thickness of passivation layer on the treated Ru surface increased with the increase of chemical A concentration. The etch rate and removal rate of Ru were increased by the addition of chemical A. The removal rate was highest m slurry of pH 9 with the addition of 0.1 M chemical A and 2 wt% alumina at 4 psi. The maximum removal rate is about 80 nm/min.

• Journal of the Korean institute of surface engineering
• /
• v.55 no.4
• /
• pp.231-235
• /
• 2022

As environmental pollution becomes more serious, the demand for electric vehicles (EVs) and lithium-ion batteries for electric vehicles is rapidly increasing worldwide. Accordingly, the amount of waste batteries is also increasing, and a technology for recycling and reusing them is required. In order to reuse a used battery, it is necessary to non-destructively diagnose the deterioration condition of the battery. Therefore, in this study, we investigate the diagnosis of degradation for parallel-connected lithium-ion battery cells through non-constructive electrochemical approach. As the number of parallel-connected cells increased, in addition to linear degradation, abrupt step-like degradation occurred, which is attributed to the predominant degradation of specific cells. In addition, it is confirmed that deteriorated cells among multiple cells can be distinguished through a simple measurement of open circuit voltage (OCV).

• Korean Chemical Engineering Research
• /
• v.61 no.4
• /
• pp.584-590
• /
• 2023

In this study, we focus on the recycling of cardboard waste and sugarcane bagasse (SCB) for the preparation of carboxymethyl cellulose (CMC) and its conversion into a biodegradable film. Sodium alginate (SA) was added to form a biodegradable composite film. SA was used to increase film permeability. Glycerol, which is a plasticizer, was used to increase the tensile strength (TS) and film expansion. To characterize the CMC, X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy were used. The addition of olive oil to the CMC-SA matrix highlighted its antimicrobial property against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). A slight decrease in tensile strength was observed with the addition of olive oil (OO), which improved the functional properties of the control films as well as lowered moisture content and water solubility. But considering all other factors, the composite films obtained from sugarcane bagasse and cardboard waste incorporated with olive oil are suitable for applications in the field of food packaging.

• Bulletin of the Korean Chemical Society
• /
• v.10 no.4
• /
• pp.366-368
• /
• 1989

The 3-formyl-2-cephem 4, available from 7-aminocephalosporanic acid has been converted to C-3 vinylic cephems. The reactions involved are the Grignard addition to 4, the conversion of the resulting alcohols to mesylates, and the elimination of the mesyl group by LiCl. When ethylmagnesium iodide is used, only 3-[(E)-1-propenyl] cephem is obtained, which is not easily available by conventional Wittig reaction.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2008.10a
• /
• pp.569-571
• /
• 2008

The structural and optical properties on $Bi^{3+}$ addition in (Y,Gd)(V,P)$O_4:Eu^{3+}$ red phosphor were investigated. With the addition of $Bi^{3+}$, the band edge in excitation spectrum shifts toward longer wavelength region, resulting in remarkable enhancement of the red emission intensity at 619 nm.

• Journal of the Korean Ceramic Society
• /
• v.18 no.2
• /
• pp.112-118
• /
• 1981

A study was made on the processing of domestic blast furnace slag by flotation and chemical purification for the use of slag as a raw material in making soda lime glasses. Feasibility study has been made for the use of reprocessing slag as a source material for both coloring and chemical components (such as CaO, $Al_2O_3$, MgO and etc.) in the glass making process. Chemical composition of chemically purified slags ranges; $SiO_2$ 34.5~37.5, $Al_2O_3$, 16.2~14.1, $Fe_2O_3$ 0.33~0.14, CaO 34.5~38.8, MgO 4.0~5.2, NmO 0.16~0.39, $TiO_2$ 0.23~0.35, S 0.08~0.42, ignition loss 3.3~8.4 and others 0.48~0.51%. It was found that either amber or greenish color could be easily obtained with the addition of salg up to 24%, however the slag addition to glass batches much impaired the transmitancy of glass products, thus a glass made with 7% slag addition showed 82% in transmitancy value at 510 nm.

• Journal of the Korean Chemical Society
• /
• v.16 no.4
• /
• pp.232-240
• /
• 1972

The rate constants for the addition reaction of n-butylmercaptan to ethylacrylate have been measured by iodometry and for the proposed reaction mechanism a rate equation which can be applied over wide pH range was derived. From this rate equation, one may conclude that the reaction is started by addition of n-butylmercaptan molecule below pH 4. However, above pH 7, this addition reaction is proceeded by the n-butylmercaptide ions. At pH 4-7, the complex addition reaction mechanism can also be revealed by this rate equation.

• Journal of the Korean Chemical Society
• /
• v.12 no.3
• /
• pp.106-113
• /
• 1968

The rate-constants of the nucleophilic addition reaction of n-butylmercaptan to 3,4-methylenedioxy-${\beta}$-nitrostyrene were determined at various acidic pH and a rate equation which can be applied over wide pH range was obtained. From this equation, one may conclude that this reaction is started by addition of mercaptan molecule below pH 3, while above pH 6, the overall rate of addition is almost only depend upon the concentration of nitrostyrene and the mercaptide ion. At pH 3∼6, the complex mechanism of this addition reaction can also be fully explained by the rate equation.

• Journal of the Korean Chemical Society
• /
• v.13 no.4
• /
• pp.289-296
• /
• 1969

The rate constants for the addition reaction of ethylmercaptan to ethylcinnamate has been measured by iodometry and for the proposed reaction mechanism a rate equation which can be applied over wide pH range was derived. From this rate equation, one may conclude that the reaction is started by addition of ethylmercaptan molecule below pH 3. However, above pH 7, this addition reaction is proceeded by the ethylmercaptide ion. At pH 3-7, the complex addition reaction mechanism can also be revealed by this rate equation.

• Journal of the Korean Chemical Society
• /
• v.10 no.4
• /
• pp.158-160
• /
• 1966

The nucleophilic addition constants 3,4-methylenedioxy-${\beta}$-nitrostyrene were determined for various nucleophiles. Considerably more data would be desirable, but it appears at present that there is no proportionality between the nucleophilic addition and substitution constant.