Spectrophotometric Determination of Iron with 2-Hydroxybenzaldehyde-5-nitro-pyridylhydrazone after Separation with Amberlite XAD-7 Nonionic Resin

박찬일,장병두,정덕채,차기원,Park, Chan Il,Chung, Byung Doo,Jung, Duck Chae,Cha, Ki Won Korean Chemical Society 1999 대한화학회지 Vol.43 No.5

2-Hydroxybenzaldehyde-5-nitro-pyridylhydrazone(2HB-5NPH)를 합성하여 철의 분광학적 정량에 응용하였다. 이 시약은 pH 6.0-7.5 범위에서 철과 반응하여 메탄올 용액에서 매우 안정한 노란색의 1:2킬레이트를 형성한다. 철의 농도범위가 0.05∼2.0 ${\mu}gmL^{-1}$일 때 Beer's law에 적용되고 미량의 철을 분광학적으로 정량하기 위하여 Amberlite XAD-7 비이온성 킬레이트 수지로 채워진 짧은 컬럼을 사용하여 분리과정에 적용하였다. 몇가지 이온들의 방해 효과를 연구하였다. 혼합용액으로부터 철이온의 분리는 완충용액(pH 5.0)과 용리액으로서 0.25M HCl을 가지고 수행하였다. 2-Hydroxybenzaldehyde-5-nitro-pyridylhydrazone (2HB-5NPH) was synthesized and its application to the spectrophotometric determination of iron was studied. The reagent reacts with iron in the pH range 6.0-7.5 to form a yellow coIored 1:2 chelate which is very stable in methanol solution. Beer's law is obeyed in the concentration range 0.05∼2.0 ${\mu}gmL^{-1}$ iron and separation procedure using a short column filled with Amberlite XAD-7 nonionic chelating resin is proposed for the spectrophotometric determination of traces of iron. The influence of several ions as interference was discussed. The separation of Fe(III) ion from the mix-ture solution were carried out with the buffer solution (pH 5.0) and 0.25M HCl as eluents.

Squamous Cell Carcinoma of the Supraglottic Larynx Treated with Radiation Therapy

박찬일,김광현,Park, Charn-Il,Kim, Kwang-Hyun The Korean Society for Radiation Oncology 1989 Radiation Oncology Journal Vol.7 No.1

1979년 3월부터 1984년 2월까지 성문상부의 편평상피암으로 진단되어 근치적 방사선치료를 시행한 66명을 대상으로 치료성적을 분석하였다. 전체 환자군의 최소 추적기간은 4년이었다. 진단당시 전체 환자군의 $78\%$가 T3 T4 병변이었고 임파절 전이율은 $58\%$이었으며, 전체 환자군의 5년 생존율은 $31.3\%$, 병기에 따른 생존율은 병기 II, III, IV에서 각각 $60.7\%,\;46.7\%\;및\;13.5\%$이었다. 3명의 환자$(5\%)$에서 원격전이가 관찰되었으며 수술을 요하는 주부작용률은 $11\%$이었다. 방사선치료 후 잔유병변 또는 재발에 대한 구제수술 성공률은 $57\%$이었다. 병기 I, II및 병기 III 초기의 성문상부암은 방사선 단독 치료만으로도 높은 근치율과 생존자의 성대기능 보존이 가능 하나, 병기 III과 IV의 성문상부암 환자 중 경부에 전이된 임파절의 절제가 가능한 환자는 수술과 방사선치료의 병용이 권장된다. Sixty-six patients with squamous cell carcinoma of the supraglottic larynx received irradiation with curative intent between 1979 and 1985 were retrospectively analysed. All patients had a minimum follow-up of 4 years. Of the entire group consisting of $73\%$T3 and T4 lesions and $58\%$ lymph node metastases, a 5-year acturial survival rate was $31.3\%$. A 5-year acturial survival rates for stage II, III and IV were $60.7\%,\;45.7\%\;and\;13.5\%$ respectively (p<0.05). Patients without lymphnode metastases had better survival rate than those with postive lymphnode metastases $(54.8\%\;vs\;12.2\%)$ (p<0.005). Surgical salvage rate w8s 4/7 $(57\%)$. Three patients developed distant metastases. Major complications requiring surgery were seen in $11\%$, Radiation therapy alone with surgical salvage was an effective, voice preserving treatment for stage I, II and selected III carcinoma of the supraglottic carcinoma, however planned combined treatment with surgery and radiation therapy is advised for stage III and IV carcinoma of the supraglottic larynx with resectable neck disease.

리드오차의 영향에 대한 헬리컬 기어 소음의 실험적 연구

박찬일,이장무,Park, Chan-Il,Lee, Jang-Mu 대한기계학회 2001 大韓機械學會論文集A Vol.25 No.9

Nowadays reduction of gear noise in power transmission is very important, because the noise regulation is severe and demand of customer on noise is increased. To reduce gear noise, it is necessary to understand the noise characteristics of helical gear. In this work, we designed test rig for the study of gear noise and installed in semi-anechoic chamber. By using this rig, sound pressure level is measured under varying rotational speed and torque. The frequency characteristics of helical gear noise on the effect of lead errors and torque are discussed.

Separation and Preconcentration Method for Palladium, Platinum and Gold from Some Heavy Metals Using Amberlite IRC 718 Chelating Resin

박찬일,정진성,차기원,Park, Chan Il,Jeong, Jin Seong,Cha, Gi Won Korean Chemical Society 2000 Bulletin of the Korean Chemical Society Vol.21 No.1

Ge(Ⅳ)-Mercaptoacetic Acid 착물에 의한 흡착벗김 전압-전류법

박찬일,성숙희,차기원,Park, Chan Il,Seong, Suk Hee,Cha, Ki Won 대한화학회 1999 대한화학회지 Vol.43 No.1

The adsorptive stripping voltammetric determination method of trace germanium (IV) using mercaptoacetic acid as a ligand was studied. Optimal conditions were found to be 0.25 M NaCl solution (pH 6.0) containing mercaptoacetic acid concentration of $5.0{\times}10^{-6}M$. The peak potential appeared at - 1.402 V vs. Ag/AgCl. Effects of sodium chloride concentration, mercaptoacetic acid concentration, and accumulation time for the complex of Ge(IV)-Mercaptoacetic acid on the peak current were studied. Amberlite IRC-718 chelating resin was applied to the separation of Ge(IV) from other metal ions. Mercaptoacetic acid를 이용하여 흡착벗김 전압전류법으로 미량의 게르마늄을 정량하는 방법을 연구하였다. 이때 지지전해질은 0.25 M NaCl 용액(pH 6.0)을 사용하였고, mercaptoacetic acid의 농도는 $5.0{\times}10^{-6}M$이 되도록 조절하여 실험하였다. Ge(IV)-Mercaptoacetic acid 착물의 봉우리 전위는 -1.402V vs. Ag/AgCl에서 나타났다. 착물의 봉우리 전위에 미치는 NaCl의 농도, mercaptoacetic acid의 농도, 축적 시간등에 대하여 조사하였다. 또한, Amberlite IRC-718 킬레이트 수지를 다른 이온들로 부터 Ge(IV)을 분리하는데 적용하였다.

태양전지 응용을 위한 ZnO:Al 박막의 전기적·물리적 특성에서 증착 온도의 영향

박찬일,Park, Chan Il 한국전기전자재료학회 2021 전기전자재료학회논문지 Vol.34 No.1

In the case of ZnO:Al thin films, it is the best material that can replace ITO that is mainly used as a transparent electrode in electronic devices such as solar cells and flat-panel displays. In this study, ZnO:Al films were fabricated by using the RF dual magnetron sputtering method at various substrate temperatures. As the substrate temperature increased, the crystallinity of the ZnO:Al thin films was improved, and the electrical conductivity and electrical properties of the thin film improved owing to the increase in grain size. In addition, the surface roughness of the ZnO:Al thin films increased due to changes in the surface and density of the thin films. Moreover, the substrate temperature increased the density of thin films and improved their transmittance. To be applied to solar cells and other several electronic devices in the future, the hardness and adhesion properties of the thin film improve as the substrate temperature increases.

The Result of Radiotherapy in Esophageal Cancer

박찬일,최은경,정웅기,방영주,김노경,Park, Charn-Il,Choi, Eun-Kyung,Chung, Woong-Ki,Bang, Yung-Jue,Kim, Noe-Kyeong The Korean Society for Radiation Oncology 1988 Radiation Oncology Journal Vol.6 No.2

1979년 3월부터 1986년 8월까지 식도의 편평상피암으로 진단되어 서울대학교병원 치료방사선과에서 방사선치료를 받은 177명중 근치적 방사선 치료를 시행한 152명을 대상으로 후향성 분석을 시행하여 다음과 같은 결과를 얻었다. $80\%$이상의 환자에서 관해를 보였으며, 이중 완전관해는 $22\%$, 부분 관해는 $63\%$이었다. 전체 환자의 2년, 5년 생존율은 각각 $22.9\%,\; 13.3\%$이었으며 식도암의 위치, 크기, 병기 그리고 관해 정도에 따라 생존율에 차이가 있었다. 식도 촬영상 5cm 이하$(17\%)$ 또는 식도의 상부 1/3에 종양이 있는 경우$(25.6\%)$에 가장 좋은 5년 생존율을 보였다. 관해 정도에 따른 생존율은 완전관해를 보인 경우의 5년 생존율이 $34.3\%$인 반면 반응이 없던 경우는 $0\%$이었다 During the period between March 1979 and August 1986, 177 patients with carcinoma of the esophagus were treated with radiotherapy in the Department of Therapeutic Radiology, SNUH. Among these, 25 patients who had incomplete treatment were excluded. So a retrospective analysis was undertaken of 152 patients who were treated by curative radiotherapy. More than $80\%$ showed response: Complete remission $(22\%)$, partial remission $(63\%)$ and no response $(15\%)$. The overall two-year and five-year actuarial survival rate were $22.9\%\;and\;13.3\%$ respectively. Prognostic factor was analyzed by its site, size, T stage, and tumor response. Patients with the best five-year survival rate were those who had the tumor no more than 5cm in length $(17\%)$ or confined to the upper third of the esophagus $(20.6\%)$. Complete responders had $34.3\%$ of 5-year actuarial survival, but no responders had $0\%$ of survival.

Determination of Trace Amounts of Nickel(II) with ${\alpha}-(2-Benzimidazolyl))-{\alpha}'{\alpha}$

박찬일,김현수,차기원,Park, Chan Il,Kim, Hyeon Su,Cha, Gi Won Korean Chemical Society 2000 Bulletin of the Korean Chemical Society Vol.21 No.5

A method is described for the fluorimetric determination of nickel, based on the formation of $Ni(II)-\alpha-(2-Benzimidazolyl)-\alpha'$, $\alpha''$ -(N-5-Nitro-2-Pyridylhydrazone)-toluene complex in the presence of a non-ionic surfactant. The complex has practically no fluorescence in the absence of surfactant, but the addition of Triton X-100 makes possible the fluorimetric determination of low concentrations of Ni(II) as it enhances the fluorescenceintensity of the complex by up to about 5-fold. This method is very sensitive and selectrive for the direct determination of nickel ion. The optimum conditions are a Triton X-100 concentration of 2.0 mL(5.0%, v/v) and pH $9.0\pm0.2(ammonium$ chloride-ammonia buffer). The fluorescence is measured at 337 nm of emission wavelength under 300 nm of excitation wavelength. The fluorescence intensity is a linear function of the concentration of Ni(II) in the range 5-70 ng/mL, and the detection limit is 2.0 nm/mL. The proposed method has been successfully applied to the determination of trace amounts of Ni(II) in food and human hair samples.

치형오차를 가진 헬리컬기어의 진동특성에 관한 연구

박찬일,이장무,Park, Chan-Il,Lee, Jang-Moo 대한기계학회 1996 大韓機械學會論文集A Vol.20 No.5

Gear vibration is caused by the mesh stiffness, gear accuracy, and assembling errors. For these reasons, helical gear has the azial, radial, and rotational vibrations. In this study, the mesh stiffness is calculated by considering the tooth bending, contact, and foundation deformations. Rotational vibration of helical gear with tooth error is modeled by the nonlidear equation of motion with single degree of freedom and is anlyzed numerically. Also, by a specially designed experimental set-up, the analysis are cross-checked and the vibration characteristics of helical gear are discussed.

축과 베어링 변형을 고려한 헬리컬 기어의 전달오차 해석

박찬일,조도현,Park, Chan-Il,Cho, Do-Hyun 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.10

Transmission error is highly related to gear noise. In order to predict the helical gear noise, transmission error analysis is needed. Up to now, the studies for the transmission error were conducted by the modeling of helical gears only. However, since helical gears are supported by the shaft and bearing, transmission error has the effects of the elements. In this study, the procedure to consider the shaft deformation with bearing stiffness for the transmission error analysis is proposed. To do so, the relationship between gear error and shaft deformation is analytically derived. Shaft deformation with bearing stiffness is analyzed by FEM. It is measured in the experimental test rig by the non-contact displacement sensors. Using the tooth error from tooth modification and the shaft deformation, the effects of shaft on the loaded transmission error are investigated.