• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.72-74
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• 2004

In this study, we used a inductively coupled plasma (ICP) source for etching $Al_2O_3$ thin films because of its high plasma density, low process pressure and easy control bias power. $Al_2O_3$ thin films were etched using $Cl_2/BCl_3$, $N_2/Cl_2/BCl_3$, and Ar/$Cl_2/BCl_3$ plasma. The experiments were carried out measuring the etch rates and the selectivities of $Al_2O_3$ to $SiO_2$ as a function of gas mixing ratio, rf power, and chamber pressure. When $Cl_2$ 50% was added to $Cl_2/BCl_3$ plasma, the etch rate of the $Al_2O_3$ films was 118 nm/min. We also investigated the effect of gas addition. In case of $N_2$ addition, the etch rate of the $Al_2O_3$ films decreased while $N_2$ was added into $Cl_2/BCl_3$ plasma. However, the etch rate increased slightly as Ar added into $Cl_2/BCl_3$ plasma, and then further increase of Ar decreased the etch rate. The maximum etch rate was 130 nm/min at Ar 20% in $Cl_2/BCl_3$ plasma, and the highest etch selectivity was 0.81 in $N_2$ 20% in $Cl_2/BCl_3$ plasma. And, we obtained the results that the etch rate increases as rf power increases and chamber pressure decreases. The characteristics of the plasmas were estimated using optical emission spectroscopy (OES).

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.579-581
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• 2010

Solid silica supported ferric chloride ($SiO_2-FeCl_3$) catalyzed one-step synthesis of various benzimidazoles from o-phenylenediamine and aldehydes using $H_2O_2$ as the oxidant. The salient features of this method are simple and convenient procedure, easy purification and shorter reaction times.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.3
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• pp.1-5
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• 2000

Inductively coupled plasma (ICP) excited by a spiral planar antenna is used to etch elctrodes for PZT capacitors. Pt/RuO$_{2}$ bilayers are tested as bottom electrodes for PZT capacitors in order to utilize better leakage characteristics of Pt and easy etch characteristics of RuO$_{2}$ at the same time. The etch rates and selectivities to SiO$_{2}$ hard mask have been measured for each of Pt and RuO$_{2}$ in terms of various plasma conditions. As Cl$_{2}$ ratio increases in $O_{2}$/Cl$_{2}$ mixture, the etch rate of Pt increases while that of RuO$_{2}$ reaches the highest near 10 ％ of Cl$_{2}$. Optimum gas mixture ratio has been determined for etching Pt and RuO$_{2}$ bilayers sequentially, and sub-half micron patterning is demonstrated.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.04a
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• pp.78-83
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• 1999

In this paper the extinction coefficients of molecule chlorine ($Cl_2$), chlorine dioxide (ClO$_2$), hypochlorous acid (HClO), chlorous acid ($HClO_2$$_2$) were determined using a PDA UV-VIS spectrophotometer. Based on these, the concentrations of $Cl_2$, $ClO_2$, and HClO in general chlorine dioxide bleaching liquor can be measured. The concentrations of $Cl_2$, $ClO_2$ and $HClO_2$ produced during the generation of methanol based chlorine dioxide generator can also be determined use the same method. The method was thought to be able to give more information in chlorine dioxide bleaching chemistry if combine its use with titration and ion chromatography.

• Journal of the Microelectronics and Packaging Society
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• v.24 no.4
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• pp.85-90
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• 2017

The $TiCl_4$ as a blocking material is adsorbed in the mesoporous $TiO_2$ electron transfer layer(ETL) of the Perovskite solar cell to prevent the direct contact between the FTO electrode and the photoactive layer(AL), and facilitate the movement of the electrons between $TiO_2:TiCl_4$ ETL and Perovskite AL to improve the photoelectric conversion efficiency(PCE). The structure of the perovskite solar cell is FTO/$TiO_2:TiCl_4$/Perovskite($CH_3NH_3PbI_3$)/spiro-OMeTAD/Ag. It was investigated that the dipping time of the $TiO_2$ into $TiCl_4$ aqueous solution affects on the photoelectric characteristics of the device. By the dipping for 30 minutes, the PCE of the perovskite solar cell with the $TiO_2:TiCl_4$ ETL was the highest 10.46%, which is 27% higher than the cell with $TiO_2$ ETL. From SEM, EDS, and XRD characterization on the $TiO_2:TiCl_4$ ETL and the perovskite AL, it was measured that the decrease of the porosity of the $TiO_2$ layer, the detection of the Cl component by the $TiCl_4$ adsorption, the cube-type morphology of perovskite AL, and shift of the $PbI_2$ peak of the perovskite AL. From these results, it was confirmed that the $TiO_2:TiCl_4$ ETL and the perovskite AL were formed.

• Preventive Nutrition and Food Science
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• v.10 no.2
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• pp.122-129
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• 2005

Chlorine dioxide $(ClO_2)$ treatment was evaluated for microbial growth inhibition and its effects on the quality of vacuum-packaged chicken breasts. Chicken breast samples were treated with 3, 50, and 100 ppm of $ClO_2$ solution, respectively. After $ClO_2$ treatment, chicken breast samples were individually vacuum-packaged and stored at $4^{\circ}C$, a typical storage temperature for meat and meat product, for 7 days. The vacuum-packaged chicken breasts treated with $ClO_2$ had significantly lower total bacteria, yeast and mold, total coliform, and Salmonella spp. were significantly reduced by $ClO_2$ treatment. $D_{10}-values$ of total bacteria count, yeast and mold, total coliform, and Salmonella spp. in vacuum-packaged chicken breasts was 93, 83, 85, and 50 ppm, respectively. The pH of vacuum-packaged chicken breasts decreased with increasing $ClO_2$ concentration. Thiobarbituric acid reacted substance (TBARS) values of vacuum-packaged chicken breasts increased during storage, regardless of $ClO_2$ concentration. $ClO_2$ treatment caused negligible changes in Hunter L, a, and b values in the vacuum-packaged chicken breasts. Sensory evaluation of the vacuum-packaged chicken breasts showed that there were no significant changes among the samples treated with various $ClO_2$ concentration. These results indicate that $ClO_2$ treatment could be useful in improving the microbial safety and quality of meat products.

• The Korean Journal of Pharmacology
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• v.20 no.1 s.34
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• pp.1-11
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• 1984

The present study was performed to determine oxygen metabolites involved in cell-free MPO/$H_2O_2/Cl^-$ system by observing the effects of their scavengers on NADH oxidation and ethylene production from methional by the action of MPO prepared from human leukocytes. It was clearly demonstrated that NADH was oxidized by the cell-free MPO/$H_2O_2/Cl^-$ system as evidenced by complete inhibition of the oxidation of the substrate in the presence of eiher azide or catalase, or by omitting $Cl^-$. The MPO-mediated oxidation of NADH was completely abolished by a $^1O_2$ quencher, DABCO but not by $OH{\cdot}$ scavengers, mannitol, benzoate, formate and methanol. In ethylene assay, no ethylene was detected from methional in the MPO/$H_2O_2/Cl^-$ system with evident production of the gas by xanthine-oxidase and $Cu^{++}-H_2O_2$ systems which are suggested to generate $OH{\cdot}$. From the results obtained, it is concluded that $^1O_2$ is a major mediator with exclusion of $OH{\cdot}$ involvement in the cell-free MPO-mediated oxidation.

• Journal of the Korean Ceramic Society
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• v.34 no.4
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• pp.436-442
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• 1997

The bimodal distribution of CuCl nano-crystals precipitated in alumino-borosilicate glass matrix (30SiO2-45B2O3-7.5Al2O3-7.5Na2O-7.5CaO-2.5GeO2(mole %)) was investigated by TEM and the temperature dependent optical spectroscopy. Two types of CuCl particles with different size were observed by TEM and it was confirmed by the splitting of Z3 absorption peak at low temperature and the occurrence of deflection point in the optical spectra with temperature.

• Journal of the Korean Chemical Society
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• v.38 no.7
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• pp.485-495
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• 1994

Several new symmetric and asymmetric homo and hetero dinuclear complexes of the type $[Cl(dppp)(NO)_2M({\mu}-pyz)M'(NO)_2(dppp)Cl][ClO_4]_2$ and $[Cl(phen)(NO)_2M({\mu}-pyz)M'(NO)_2(dppp)Cl][ClO_4]_2$(M,M'= Mo or W; phen = 1,10-phenanthroline; dppp = 1,3-bis(diphenylphosphino)propane; pyz = 1,4-pyrazine) were synthesized in three-steps starting from $[M(NO)_2Cl_2]_n(M = Mo, W)$. The final products were purified by eluting it through silica gel column ($2{\times}20$ cm) with acetone as the eluent. Characterization of these complexes and some related complexes was accomplished through UV-vis., $^1H$-NMR, $^{13}C$-NMR and IR spectroscopies as well as elemental analysis. The infrared spectra indicate that the NO groups occupy cis-positions of the octahedral. The $^1H$ and $^{13}C-NMR$ data for the new compounds revealed a dimeric structures with bridged pyz.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.3
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• pp.415-420
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• 2020

Strontium is known as a salt-soluble element during the electrolytic oxide reduction (EOR) process. The chemical behavior of SrO during EOR was investigated via thermodynamic calculations to provide quantitative data on the chemical status of Sr. To achieve this, thermodynamic calculations were conducted using HSC chemistry software for various EOR conditions. It was revealed that SrO reacts with LiCl salt to produce SrCl₂, even in the presence of Li₂O, and that the ratio of SrCl₂ depends on the initial concentration of Li₂O dissolved in LiCl. It was found that SrO reacts with Li to produce Sr during EOR and that the reduced Sr reacts with LiCl salt to produce SrCl₂. As a result, the proportions of metallic forms were lower in Sr than in La and Nd under various EOR conditions. The thermodynamic calculations indicated that the three chemical forms of SrO, SrCl₂, and Sr co-exist in the EOR system under an equilibrium with Li, Li₂O, and LiCl.