• 대한화학회지
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• 제14권1호
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• pp.123-126
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• 1970

The approximate crystal structure of benzidine monoperchlorate has been determined by single crystal X-Ray diffraction technique and patterson method. As the molecule has a center of symmetry in it and location of perchlorate ion is symmetrically on the mirror plane in the unit cell, perchlorate ion is forming hydrogen bond with two -$NH_2$ groups in the different molecule. Thus, one molecule of benzidine and perchloric acid combines 1:1 by mole ratio.

• 응용화학
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• 제16권1호
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• pp.25-28
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• 2012

A determination method of cyanide ion (CN^-) using nickel complexation reaction by continuous monitoring system. The mechanical parameters and chemical conditions of the complexation reaction were investigated prior to application of continuous monitoring system for determination of cyanide. On the optimized conditions, the calibration curve was linear over the range from 5.0×10^-6 to 1.0×10^-4 M. In this range, 2.40% of the reproducibility (RSD, n=3) was obtained. The limit of detection (3σ/s) was calculated to be 1.8×10^-6 M.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.161.1-161.1
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• 2003

Two chitosanses produced by Aspergillus fumigatus KB-1 were purified by ion exchange and size exclusion chromatographies. Molecular weights of chitosanses were 111.23 KDa (chitosanase I) and 23.38 KDa (chitosanase II). The N-terminal amino acid sequence of chitosanase II was determined: YNLPNNLKQIYDKHKGKXSXVLAK(\ulcorner)GFTN. The optimum pH of the chitosanase I and II were 6.5 and 5.5 respectively. The optimum temperatures were $60^\times$C and $70^\times$. Two chitosanases were most stable at $10^\times$C. (omitted)

• Bulletin of the Korean Chemical Society
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• 제33권1호
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• pp.285-288
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• 2012

• Archives of Pharmacal Research
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• 제27권12호
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• pp.1295-1301
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• 2004

The enantiomeric composition tests on flurbiprofen and ketoprofen present in patch products and in urine excretions following patch applications were performed as diastereomeric (R)-(+)- 1-phenylethylamides by achiral gas chromatography and by gas chromatography-mass spectrometry in selected ion monitoring mode. The method for determination of (R)- and (S)-enantiomers in the range from 0.1 to 5.0 ${\mu}$g was linear (r ${\ge}$ 0.9996) with acceptable precision (% RSD ${\le}$5.2) and accuracy (% RE = 0.6 ~ -2.4). The enantiomeric compositions of flurbiprofen in one patch product and of ketoprofen in five different products were identified to be racemic with relatively good precision (${\le}$ 6.4%). The urinary excretion level of (R)-flurbiprofen was two times higher than its antipode, while the comparable excretion levels of (R)- and (S)-enantiomers for ketoprofen were observed.

• 대한금속재료학회지
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• 제46권1호
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• pp.20-25
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• 2008

The ionic equilibira in mixed solutions of cuprous and cupric chloride were analyzed by considering chemical equilibria, mass and charge balance equations. The activity coefficients of solutes were calculated by using Bromley equation. Required thermodynamic constants and interaction parameters were evaluated from the data reported in the literature. The effect of NaCl and CuCl concentrations on the pH and potential of the mixed solutions was explained in terms of the variation in the concentration of solutes and in the activity of hydrogen ion. The calculated pH values of the mixed solutions agreed well with the measured values. However, the calculated values for the potential of the mixed solutions were lower than the measured values, indicating the necessity of considering the complex formation between cuprous and chloride ion, such as $Cu^2Cl{_4}^{2-}$ and $Cu_3Cl{_6}^{3-}$.

• 한국환경보건학회지
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• 제36권4호
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• pp.306-312
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• 2010

This field study was performed to evaluate the efficiency of a plasma ion-operated air cleaner in temporal reduction of airborne pollutants emitted from a pig housing facility. In the case of gaseous pollutants, the plasma ion air cleaner was not effective in reducing levels of ammonia, hydrogen sulfide, nitrogen dioxide, or sulfur dioxide (p>0.05). In the case of particulate pollutants, however, the air cleaner was effective in reducing levels of particulate matter ($PM_{2.5}$ and $PM_1$) by 79(${\pm}6.1$) and 78(${\pm}3.0$)%, respectively. Unlike the case of these fine particle fractions, the reduction of total suspended particles (TSP) and $PM_{10}$ following treatment was almost negligible. In the case of biological pollutants, the mean reduction efficiencies for airborne bacteria and fungi were relatively low at 22(${\pm}6.6$) and 25(${\pm}8.7$)%, respectively. Taken together, these results indicate that in terms of air pollutants released from this pig housing facility, the plasma ion air cleaner was primarily effective in reducing levels of $PM_{2.5}$ and $PM_1$.

• 한국세라믹학회지
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• 제42권1호
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• pp.28-32
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• 2005

이중 이온빔 스퍼터링(Dual ion-Beam Sputtering, DIBS)과 단일 이온빔 스피터링(Single ion-Beam Sputtering, SIBS)을 사용하여 기판의 온도와 보조 이온빔 에너지 변화에 따라 $Ta_{2}O_{5}$ 박막의 광학적 특성과 박막에 존재하는 응력의 변화에 과해 관찰하였다. SIBS 방법에 의해 증착되어진 박막의 굴절률은 150^{circ}C$에서 최고 2.144를 나타내었으며, $150^{circ}C$ 이상에서는 감소하였다. DIBS 방법에 의해 증착된 732린 박막은 기판의 온도가 증가함에 따라 $200^{circ}C$에서 최고 2.117의 굴절률을 나타내었다. $100^{circ}C$ 미만의 저온 DIBS 증착은 박막에 존재하는 응력을 낮추었으나 100^{circ}C 이상의 고온 증착시에는 박막에 존재하는 응력이 켰다. 보조 이온빔 어시스트 한 경우, 보조 이온빔 에너지가 250V에서 350V로 증가함에 따라 증착된 T놀달 박막의 굴절률은 2.185로 증가하였으나, $350\~650V$인 구간에서는 굴절률이 감소하는 경향을 나타냈다. 또한, 보조 이온빔 에너지가 증가함으로써 박막에 존재하는 응력이 감소하여 650 V에서 0.1834 GPa를 나타내었다.

• 약학회지
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• 제34권3호
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• pp.215-218
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• 1990

An ion chromatographic method based on indirect photometric detection of UV transparent anions was developed. Separation of anion was accomplished on strong anion exchange column (Waters SAX) using UV detector at 254 nm. Among examined UV-active additives (Dns-H, Dns-glu, Dnsser, Dns-val), Dns-glu showed the highest sensitivity. Studies on the effects of the pH and ionic strength of eluent revealed that the increase of pH and ionic strength of the eluent decreased capacity factor. The best eluent for the separation of acetate, fluoride, chloride, nitrate and bromide was $1\;{\times}\;10^{-4}M$ Dns-glu in 5 mM phosphate buffer (pH 6.30). The detection limit of chloride ion was 2.1 ng in this condition.

• Bulletin of the Korean Chemical Society
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• 제5권6호
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• pp.249-253
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• 1984

Mutual diffusion coefficients of choline chloride were determined by using the diaphragm cell method in aqueous solutions of chondroitin sulfate A at $25^{\circ}C$. The diffusion coefficients of choline chloride in 0.1g/100ml, 0.5g/100ml and 1g/100ml respectively of chondroitin sulfate solutions were compared with those of binary systems of water-choline chloride. At low concentrations, the diffusion coefficients of the choline chloride in the presence of chondroitin sulfate were significantly smaller than the values obtained in the absence of chondroitin sulfate, indicating a strong interaction between these solutes. The effect of this interaction on the diffusion of choline ion is largest at higher chondroitin sulfate concentrations and at lower choline chloride concentrations. The influence of chondroitin sulfate is overcome at higher choline chloride concentrations. Self-diffusion coefficients of choline ion in the presence of chondroitin sulfate are also obtained. Excellent agreements were obtained between the experimental data and the calculated values obtained by using the Manning's equations. These observations suggest that the interaction between choline chloride and chondroitin sulfate involves primarily a long range electrostatic effect and there is no appreciable "condensation" or binding of choline ion to the chondroitin sulfate.