• Bulletin of the Korean Chemical Society
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• v.29 no.3
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• pp.627-640
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• 2008

The geometrical structures, atomic charges, and relative energies of tetracoordinated Pd complexes [PdCl3Z (Z = Cl-, Br-, OH?-, H2O, NH3, PH3), PdCl2Z2 (Z = Br-, OH?-, H2O, NH3, PH3), PdZ?2X (Z = Cl-, OH?-, H2O, NH3, PH3; X = oxalate, O2-?CCO2-), and PdZ2Y (Z = Cl?-, OH?-, H2O, NH3, PH3; Y = succinate, CO2-?CHCHCO2-?)] and the ligand exchange reactions of the Pd complexes were investigated using the ab initio second order Mller-Plesset perturbation (MP2) and Density Functional Theory (DFT) methods. The geometrical characteristics of the tetracoordinated Pd(II) complexes with mono- and bidentate ligands, the effects of the atomic charges for the charged and uncharged ligands, the (dz2-p ) interactions between the dz2-orbital of Pd(II) and the p -orbital of bidentates, and the relative stabilities between the isomers of PdCl2Z2 and PdZ2Y were investigated in detail. The potential energy surfaces for the ligand exchange reactions used for the conversions of {[PdCl2(NH3)2] + H2O} to {[PdCl(NH3)2(H2O)]+ + Cl?-?} and {[PdCl2(PH3)2] + H2O} to {[PdCl(PH3)2(H2O)]+ + Cl?-?]} were investigated. The geometrical structure variations, molecular orbital variations (HOMO and LUMO), and relative stabilities for the ligand exchange processes were also examined quantitatively.

• Journal of the Korean Chemical Society
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• v.37 no.7
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• pp.648-654
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• 1993

$[M(cyclam)X_2]Y(M=Co^{3+},\;Fe^{3+},\;Mn^{3+}\;:\;X=Cl-^,\;Br^-,\;NCS^-\;:\;Y=Cl^-,\;Br^-,\;NCS^-),\;[Co(trans-14-diene)X_2]Y(X=Cl^-,\;Br^-\;:\;Y=ClO_4^-)\;and\;[Co(trans-14-diene)](ClO_4)_2$ were able to activate an molecular oxygen under sodium borohydride. 2,4-di-tert-butylphenol and 2,6-di-tert-butylphenol reacted with activated molecular oxygen to give 2,4-tert-butyl-1,6-benzoquinone(BQ) and 3,5,3',5'-tetra-tert-butyldiphenoquinone(DPQ). The saturated tetraazamacrocyclic complexes, $[Co(cyclam)X_2]Y$, were more an effective catalyst than $[Co(trans-14-diene)X_2]Y$ the unsaturated complexes in the formation of BQ and DPQ. The mole ratio of $O_2$ vs. catalyst $(O_2/M)$ for $[Co(cyclam)X_2]Y$ and [Co(trans-14-diene)X_2]Y$ was 1/1, while it was 1/2 for $[M(cyclam)Cl_2]Cl(M=Fe(III),\;Mn(III))$. The results suggested that Co(III)-macrocyclic complexes activated molecular oxygen as superoxolike ${O_2}^-$ and $[M(cyclam)Cl_2]Cl(M=Fe(III),\;Mn(III))$ activated that as peroxolike $O_2^{2-}$.

• Journal of the Korean Chemical Society
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• v.45 no.5
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• pp.442-447
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• 2001

The charge-transfer compound (OMTTF)AuCl$_4$ was prepared from the direct reaction of octamethylenethiafulvalene (OMTTF) with HAuCl$_4{\cdot}xH_2$O in THF. (OMTTF)$_2PtCl_4$, (OMTTF)_2IrCl_6{\cdot}2H_2$O, and (OMTTF)Os$Cl_5{\cdot}THF$ were also formed using $H_2PtCl_6{\cdot}xH_2O$, $H_2IrCl_6{\cdot}xH_2O$ and $H_2OsCl_6$, respectively. The prepared compounds were characterized by magnetic (EPR, magnetic susceptibility), spectroscopic (IR, UV-Vis), electrochemical (CV) methods, and the powdered electrical conductivity measurement. The powdered electrical conductivities at room temperature were ~$10^{-7}S{\cdot}cm^{-1}$. The experimental results show that $OMTTF^+$ monocation radicals exist in all of the prepared compounds. The redox potential of OMTTF supports that $OMTTF^+$ is relatively stable. The magnetic properties indicate that there are significant magnetic interactions between the localized odd electrons on the central metal (Ir and Os) ions and the odd electrons resided on $OMTTF^+$ cation radicals in both (OMTTF) $_2IrCl_6{\cdot}2H_2O$ and (OMTTF)$OsCl_5{\cdot}THF$.

• Journal of the Korean Chemical Society
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• v.51 no.4
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• pp.339-345
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• 2007

Urea reacts with PtCl2, H2[PtCl6]·6H2O, H2[IrCl6] and Ni(CH3CO2)2 in aqueous solution at high temperature (60-80 °C) yielding [PtCl2(Urea)]·2H2O (1), (NH4)2[PtCl6] (2), (NH4)2[IrCl6]·H2O (3) and [Ni2(OH)2(NCO)2(H2O)2] (4) complexes, respectively. In complex 1, urea coordinates to Pt(II) as a neutral bidentate ligand via amido nitrogen atoms. In complexes 2, 3 and 4 it seems that the coordinated urea molecules decompose during the reaction at high temperature and a variety of reaction products are obtained. All complexes were isolated in moderate yields as dark green (1), yellow (2), pale brown (3) and faint green (4) precipitates, respectively. The reaction products were characterized by their microanalysis, IR, 1H and 13C NMR spectra as well as thermal analysis. General mechanisms describing the formation of these complexes were suggested.

• Korean Journal of Poultry Science
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• v.12 no.1
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• pp.25-30
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• 1985

In order to observe an effect of the components of rice straw on the utilization of nutrient in chicks, the rice straw of 100g were digested in 800$m\ell$ of distilled water or 0.25N NaClO$_2$ at 135 C and in the pressure of 3.2kg/$\textrm{cm}^2$ by autoclave during 30, 60 and 120 minutes (water or NaClO$_2$-30, 60 and 120- RS). The contents of neutral detergent fiber(NDF), acid detergent fiber (ADF) and lignin were analysed in the washed and dried rice straw meal. Hatched single comb white Leghorn male chicks were fed with a commercial chick mash for the first 10 days and five kinds of experimetal diets for the next 8 days which contained 17.0% of wheat bran (basal), cellulose(cotton meal), nontreated RS, water-30-RS and NaClO$_2$ 30-RS, respectively. The water-30, 60 and 120-RS baa leased 9.7, 12.1 and 13.3% of dry matter, respectively, while NaClO$_2$-30-RS had similar contents of dry matter loss with those of water-30-RS, and NaClO$_2$-60 and 120-RS had tossed 1.5 times of dry matter comparing with those of water-60 and 120-RS, respectively. And the dry matter loss of the water-RS or NaClO$_2$-RS was mainly originated front the extractable cell contents and hemicellulose of the non-treated RS. Birds fed water-30-RS diets had higher body weight gain and lower feed conversion than those of birds fed non-treated and NaClO$_2$-30-RS diets during 8 days of experimental feeding. Also nitrogen balance and retention rate of birds fed water -30-RS was higher comparing with those of birds non-treated and NaClO$_2$-30-RS. And digestibility of crude fat had been shown a highering trend in birds water-30-RS. The rate of metabolizable energy (MEn) to gross energy (GE) of birds fed non-treated RS, water-30-RS and NaClO$_2$30-RS diets were 71.9, 72.9 and 70.4%, respectively, and energy intake per metaboic body size (kg 0.75) were reached to 307.3, 296.2 and 291.4 kcal per day, respectively. And daily protein retention per kg 0.75 were 1.647, 1.969 and 1.560g, respectively. Then 30.56kcal of MEn required for 1 g of protein retention in birds fed water-30-RS, which was lower thu 36.90 and 37.56 kcal of birds fed non-treated and NaClO$_2$-30- RS, respectively. The results seems to indicate that non-treated rice straw had a substance or characters which affect the energy unilization or protein retention of diets and which will be eliminated by boiling in water.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.9
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• pp.611-615
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• 2001

Y$_2$O$_3$ thin films have been proposed as a buffering insulator of metal/ferroelectric/insulator/semiconductor field effect transistor(MFISFET)-type ferroelectric random access memory (FRAM). In this study, $Y_2$O$_3$ thin films were etched with inductively coupled plasma(ICP). The etch rates of $Y_2$O$_3$ and YMnO$_3$, and the selectivity of $Y_2$O$_3$ to YMnO$_3$ were investigated by varying Cl$_2$/(Cl$_2$＋Ar) gas mixing ratio. The maximum etch rate of $Y_2$O$_3$, and the selectivity of $Y_2$O$_3$ to YMnO$_3$ were 302$\AA$/min, and 2.4 at Cl$_2$/(Cl$_2$＋Ar) gas mixing ratio of 0.2 respectively. Optical emission spectroscopy(OES) was used to understand the effects of gas combination on the etch rate of $Y_2$O$_3$ thin film. The surface reaction of the etched $Y_2$O$_3$ thin films was investigated by x-ray photoelectron spectroscopy (XPS). XPS analysis confirmed that there was chemical reaction between Y and Cl. This result was confirmed by secondary ion mass spectroscopy(SIMS) analysis.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.863-866
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• 1999

(Ba,Sr)$TiO_3$ thin films have attracted groat interest as new dielectric materials of capacitors for ultra-large-scale integrated dynamic random access memories (ULSI-DRAMs) such as 1 Gbit or 4 Gbit. In this study, inductively coupled $BCl_3/Cl_2$/Ar plasmas was used to etch (Ba,Sr)$TiO_3$ thin films. RF power/dc bias voltage = 600 W/-250 V and chamber pressure was 10 mTorr. The $Cl_2/(Cl_2+Ar)$ was fixed at 0.2, the (Ba,Sr)$TiO_3$ thin films were etched adding $BCl_3$. The highest (Ba,Sr)$TiO_3$ etch rate is 480$\AA/min$ at 10 % $BCl_3$ adding to $Cl_2$/Ar. The characteristics of the plasmas were estimated using optical emission spectroscopy (OES). The change of Cl, B radical density measured by OES as a function of $BCl_3$ percentage in $Cl_2$/Ar. The highest Cl radical density was shown at the addition of 10% $BCl_3$ to $Cl_2$/Ar. To study on the surface reaction of (Ba,Sr)$TiO_3$ thin films was investigated by XPS analysis. Ion enhancement etching is necessary to break Ba-O bond and to remove $BaCl_2$. There is a little chemical reaction between Sr and Cl, but Sr is removed by physical sputtering. There is a chemical reaction between Ti and Cl, and Tic14 is removed with ease. The cross-sectional of (Ba,Sr)$TiO_3$ thin film was investigated by scanning electron microscopy (SEM), the etch slope is about $65\;{\sim}\;70$.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.11
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• pp.743-750
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• 2012

An ultraviolet (UV) absorption method has a difficulty to analyze $ClO_{2(aq)}$ in solutions containing various chlorine species because UV spectrum of $ClO_{2(aq)}$ overlaps with other chlorine-containing species. This study has proposed the deconvolution method of UV spectrum to analyze $ClO_{2(aq)}$ concentration quantitatively in solution containing various chlorine species. We compared results obtained from UV deconvolution method with titration method. Good agreement of $ClO_{2(aq)}$ concentration between them has been shown in about 10%. This result informs us that the deconvolution method of UV spectrum could be a feasible for the analysis of $ClO_{2(aq)}$ in solution containing various chlorine species.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.05a
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• pp.264-265
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• 2009

본 연구에서 유도결합 플라즈마 식각 장치외 $BCl_3/Ar/Cl_2$ 가스 혼합비를 이용하여 ZnO 박막을 식각 하였을 때, 식각 된 ZnO 박막의 표면 반응에 관하여 관찰하였다. ZnO 박막의 식각 실험 조건은 RF 전력 700 W, 직류바이어스 전압 - 150 V, 공정 압력 15 mTorr로 고정하였고, $Cl_2/(Cl_2+BCl_3+Ar)$ 가스 혼합비를 변경하면서 식각 실험을 수행하였다. $Cl_2$ 가스가 3 sccm 일 때, ZnO 박막의 식각속도는 53 nm/min으로 가장 높았으며, 이때 ZnO 박막에 대한 $SiO_2$의 선택비는 0.89 이었다. 식각된 ZnO 박막의 표면은 XRD (X-ray diffraction)와 AFM(atomic force microscopy)를 이용하여 결정상의 변화와 표면의 거칠기를 분석하였다. AFM 분석 결과에서 Ar, $BCl_3$와 $Cl_2$ 플라즈마를 이용하여 식각된 시료의 표면 거칠기 근 값이 식각전의 시료나 $BCl_3/Ar/Cl_2$ 플라즈마로 식각된 시료보다 큰 것을 확인하였다. 이는 식각된 시료에서의 Zn 양의 감소나 비휘발성 식각 잔류물에 의한 영향으로 판단된다. SIMS(secondary ion mass spectrometery) 분석을 통해 검증 하였다.

• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.400-406
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• 1999

In an effort to obtain high efficiency in gas fired absorption chillers, a new working fluid has been developed with thc addition of the component of $LiNO_3$, LiCl and LiI to the conventional solution of $LiBr-H_2O$. The solubility and vapor pressure of the 4 component working fluid developed in this work were measured and compared to the results of $LiBr-H_2O$ solution. It was observed that there exists an optimal mole ratio of the inorganic salts in terms of solubility. The mole ratio of LiBr, $LiNO_3$ and LiCl was found to be around 5:1:1~2 in the $LiBr-LiNO_3-LiCl-H_2O$ mixture, and in the case of $LiBr-LiO_3-Lil-H_2O$ and $LiBr-Lil-LiCl-H_2O$ mixtures, the mole ratio of LiBr, $LiNO_3$ and Lil/ LiBr, LiI and LiCl were found to be around 5:1:1 and 5:1:0.5~1 respectively. The vapor pressure of the 4 component working fluid of the optimal mole ratio was increascd with adding the component of $LiNO_3$, LiCl and LiI except for $LiBr-LiNO_3-LiCl-H_2O$ mixture. The absorption capacity of $LiBr-LiNO_3-LiCl-H_2O$ mixture was obtained higher than that of $LiBr-H_2O$ mixture.