Cr(Ⅲ)-EDTA착이온 [Credta(H_2O)]￣과 아세트산이온과의 치환반응의 평형상수에 미치는 압력의 효과

정종재,황정의,서형택 慶北大學校 1982 論文集 Vol.33 No.-

The equilibrium constants of substitution reaction of ethylenediaminetetraacetatoaquochromate(Ⅲ) ion with acetate ion were determined under high pressure by the spectroscopic method in order to learn how pressure governs the magnitude of the equilibrium constant of the reaction. 〔Cr(edta)(H_2O)〕^-+OAc^-??〔Cr(edta)(OAc)〕^2-+H_2O The reaction was analyzed with the thermodynamic parameters calculated from the equilibrium constants. The equilibrium constants increased as the pressure and the temperature did. The enthalpy change (ΔH°), entropy change (ΔS°) and volume change (ΔV°) of the reaction were obtained by the equilibrium constants change with the pressure and the temperature. The isoequilibrium temperatures were obtained from the isokinetic relationship between ΔH° and ΔS° for the pressure change in the reaction. From all of the above results, it was found that this reaction was endothermic and enthalpy controlled reaction in the experimental temperature.

기전력법에 의한 페놀 및 2-염화페놀의 해리반응에 미치는 압력의 영향

황정의,정종재,차성극 慶北大學校 物理化學硏究所 1984 硏究論文集 Vol.5 No.-

The dissociation constants of phenol and o-chlorophenol were measured by emf method and compared the effects of temperature and pressure with the ordinary state. The constants are varies with the temperature and pressure, i.e. those values are increased as the both temperature and pressure increased. As the hydrogen ion reversible electrode, antimony oxide electrode is qualified until pressure to 2,000 bar in ordinary temperature but at 35℃ only to 1,500 bar. From the observed constants, various thermodynamic properties are calculated and discussed on the dissociation reaction.

Cr(Ⅲ)-EDTA착이온 [Credta(H_2O)]^-과 아세트산이온과의 치환반응의 평형상수에 미치는 압력의 효과

정종재,황정의,서형택 慶北大學校 物理化學硏究所 1984 硏究論文集 Vol.5 No.-

The equilibrium constants of the substitution reaction of ethylenediaminetetraacetatoaquochromate(Ⅲ) ion with acetate ion were determined under high pressure by the spectroscopic method in order to learn how pressure governs the magnitude of the equilibrium constant of the reaction. 〔Cr(edta)(H_2O)〕^- +OA_c- ⇔ 〔Cr(edta)(OA_c)〕^2- + H_2O The reaction was analyzed with the thermodynamic parameters calculated from the equilibrium constants. The equilibrium constants increased as the pressure and the temperature did. The enthalpy change (ΔH˚), entropy change (ΔS˚) and volume change (ΔV˚) of the reaction were obtained by the equilibrium constants change with the pressure and the temperature. The isoequilibrium temperatures were obtained from the isokinetic relationship between ΔH˚ and ΔS˚ for the pressure change in the reaction. From all of the above results, it was found that this reaction was endothermic and enthalpy controlled reaction in the experimental temperature.

염화아세트산들의 해리반응에 미치는 온도와 압력의 영향

황정의,정종재,박용태,지종기,박의환 慶北大學校 物理化學硏究所 1984 硏究論文集 Vol.5 No.-

The temperature and pressure dependences of the dissociation constants of mono-, di- and tri-chloroacetic acids were studied by the conductimetry in the range of 20-35℃ and 1-2500 bars. The thermodynamic parameters ΔH, ΔS, and ΔV were evaluated from the dissociation constants. The dissociation constants were increased as the temperature and pressure was increased respectively. The pressure effects can be explained by the fact that the increase of the charges of reaction species enhances the solvation of ions and reduces the reaction volume. As the more chlorines were substituted to acetic acid, the effect of pressure on the dissociation constants was decreased because of the enhanced solvation effect. From the thermodynamic data it can be estimated that there are two types of dissociation reactions. They are an enthalpy-dominated reaction and an entropy-dominated one.

Rh(NH_3)_4AX^n+ 錯이온의 光立體化學에 對한 理論的 解釋

鄭倧在,黃正儀,崔鍾河 慶北大學校 1985 論文集 Vol.39 No.-

It is shown that the experimentally observed photostereochemical behavior of Rh(NH_3)_4AX^n+ complexes can be rationally explained in terms of the properties of the relative energy levels for the hypothetical pentacoordinate intermediates. The d-orbital and total destabilization energies for various intermediates have been analyzed within the framework of angular overlap model. Initial singlet ligand field excitation is presumed to be followed by efficient intersystem crossing to the lowest energy triplet ligand field state which undergoes a ligand A dissociation to give square pyramidal(SP) species, pentacoordinate fragments SP(X)_ax and SP(X)_eq from trans- and cis-Rh(NH_3)_4AX^n+ complexes, respectively. Rearrangement of these two square pyramidal species via the intermediacy of the trigonal bipyramidal (TBP) intermediate leads to isomerization while competitive nonradiative deactivation followed by solvent trapping leads to hexacoordinate product. The most stable intermediate is the one characterized by the smallest value of the total destabilization energy. When X is a ligand Br, the SP(Br)_ax has the lowest energy value. In that case trans-product is therefore favor. If X were a ligand CN, the SP(CN)_eq and TBP(CN)_ax would have the lowest energy value, and the product leads to cis-isomer. The theoretical prediction on the photoreaction of Rh(NH_3)_4^-AX^n+ complexes is consistent with the experimental observations of stereochemical results.

전도도법에 의한 치환 피리딘들의 해리상수 측정과 그의 온도와 압력에 따른 영향

黃正儀,鄭倧在,金學成,尹永炷,朴義煥 慶北大學校 1984 論文集 Vol.38 No.-

Generally, pyridine and most of substituted pyridines act as base in aqueous solutions. The strengths of their basicities can be expressed quantitatively by the dissociation constant of base or its conjugated acid. Generally, the acidity of substituted pyridines can be expressed by K_a of the following reaction. ◁그림 삽입▷ (원문을 참조하세요) The dissociation constants of these subtituted pyridines have not been reported under high pressure but under atmospheric pressure. In this papers, the dissociation constants of some substituted pyridines were measured under high pressure by the conductometry. From the ionic conductivity of hydrogen ion, the dissociation constants (K_a) were calculated. The K_a values were increased with increasing temperature and were decreased with increasing presure. The charateristics of dissociation process of some substituted pyridines were deduced from the thermodynamic properties calculated from the dissociation constants.

電氣的 開始法에 의한 2-Hydroxyethyl methacrylate의 重合과 이들 膜의 電氣的 性質

黃正儀,鄭倧在,車星極 慶北大學校 1978 論文集 Vol.25-26 No.-

The electroinitiated polymerization of 2-hydroxy ethyl methacrylate (HEMA) has been studied at the various voltages, from 2 to 2500 volts. The rate of polymerization was increased with increasing voltages. It was supposed that the orientation and migration effect of monomer accelerating the rate. The membranes were molded between two separated glass plates. These membranes have been used to measure the membrane potentials and the transport number of Na^+ ion and water. The measured membrane potentials and calculated values, which were related by Scatchard theory, gave satisfactory agreement below 0.1m. This was due to permselectivity of HEMA membranes, which had high fixed-OH group in the pore as a pendent. The main deviations of measured membrane potentials (E_c) and the maximum possible values of electrical potentials (E_max) were due to transport numbers of Cl^-ion and water. Therefore it seems to be make an useful strong hemodialysis HEMA membranes by electroinitiated grafting polymerization.

실리콘樹脂를 利用한 文化財保護被膜에 對한 硏究

黃正儀,朴斗元,吳相午,鄭倧在,朴裕哲,郭永佑 慶北大學校 1977 論文集 Vol.23 No.-

金屬실리콘과 鹽化메틸을 鹽化第一구리를 觸媒로 하여 메틸실란을 合成하고 메틸실란을 加水分解하여 실록산의 被膜을 만드는 方法을 調査하였다. 이들 被膜이 文化財 保護被膜이 될 수 있는가를 檢討하기 爲해서 材料를 文化財의 材質인 몇 가지 物質에 適用하여 膜의 性能을 調査하였다. 特히 撥水效果, 汲水量 耐久性等을 調査하였으며 外觀上 아무런 變化가 없는 좋은 被膜이 될수 있다는 結果를 얻었다. The organohalogensilicone was synthesized metal silicone and methylchloride applying the direct synthetic method using copperous chloride as catalyzer. The synthesized organosilane was hydrolyzed to siloxane by various method and coated on various materials which are composed of the cultural assets. The coating film was examined to decide whether it is profitable one to protect the assets from efflorescence or air pollution. Referring to the water repellency, permiability of water and the weather test of the film it was qualified that this film was good enough to apply to the cultural assets as protecting film.

분광광도법에 의한 3-Chloro 및 3-Bromopyridine의 해리상수 측정과 그의 온도와 압력에 따른 영향

黃正儀,鄭倧在,尹永炷,金學成 慶北大學校 1984 論文集 Vol.38 No.-

Pyridine and most of substituted pyridines react as base in aqueous solutions. Strength of their basicities can be represented quantitatively by the dissociation constant of a base or its conjugated acid. The dissociation constants of weak acid or base are highly dependent on the pressure and the temperature. The dissociation constants of these substituted pyridines have been reported only under the pressure of atmosphere but not high pressure. In this study, we measured the dissociation constants of 3-chloro and 3-bromopyridine under high pressure by the method of spectrophotometry. Also, we obtained the thermodynamic parameters on the dissociation reactions that show the effects of the temperature and the pressure on the dissociation constants.

전도도법에 의한 치환 피리딘들의 해리상수 측정과 그의 온도와 압력에 따른 영향

黃正儀,鄭倧在,金學成,尹永炷,朴義煥 慶北大學校 物理化學硏究所 1985 硏究論文集 Vol.6 No.-

Generally, pyridine and most of substituted pyridines act as base in aqueous solutions. The strengths of their basicities can be expressed quantitatively by the dissociation constant of base or its conjugated acid. Generally, the acidity of substituted pyridines can be expressed by K_a of the following reaction. ◁그림삽입▷(원문을 참조하세요) The dissociation constants of these subtituted pyridines have not been reported under high pressure but under atmospheric pressure. In this papers, the dissociation constants of some substituted pyridines were measured under high pressure by the conductometry. From the ionic conductivity of hydrogen ion, the dissociation constants(K_a) were calculated. The K_a values were increased with increasing temperature and were decreased with increasing pressure. The characteristics of dissociation process of some substituted pyridines were deduced from the thermodynamic properties calculated from the dissociation constants.