녹두발아중의 라이보플라빈의 생화학적연구

이철준,정동효 한국농화학회 1961 Applied Biological Chemistry (Appl Biol Chem) Vol.2 No.1

The daily variation in the total quantity of flavin compounds (FAD, FMN, FR) in greenbean during its germination were measured by Yagi's methods. The results obtained were as follow. 1. The total quantity of flavin compounds of the greenbean sprouts was increased with growth of sprouts until the 8th days. After this period its contents were decreased slightly. 2. The flavin compounds of greenbean sprouts were comfirmed to be synthesized as free riboflavin during its germination. 3. FAD was the major pat of total flavin compounds in cotyledon but there was significant variation in the contents of FAD, FMN and FR in hypocotyl.

CdS-ZnS 증착막의 Hall 효과

이철준 울산과학대학 1985 연구논문집 Vol.10 No.2

저항가열법으로 진공증착한 CdS-ZnS 증착막의 전기적 특성과 Hall 효과를 조사하였다. 측정된 Hall 계수와 전도도로부터 carrier 농도와 이동도를 산출하였다. 전도도는 온도에 따라 조금씩 감소하며, 낮은 온도에서 포화상태에 도달하는 경향이 있다. 측정온도범위에서 σ는 T^2에 선형적으로 비례하는 관계를 보였다. carrier의 농도의 온도의존성은 불순물이 첨가된 중착막은 400K에서 진성영역을 나타내고 400K이하에서는 외인성영역으로 포화상태가 나타났다. 진성영역의 온도특성으로부터 증착막의 band gap을 측정하여 그것이 성분비에 따라 2.15eV부터 2.46eV까지 선형적으로 변하는 모양을 관측하였다. 온도 의존성을 조사한 결과 이동도는 불순물의 농도에 따라 T^(-1.3)에서 T^(-0.3)까지 변하였다. 불순물이 첨가된(5×10 exp (20)/㎤) CdS 증착막은 축퇴되었고, 온도에 따른 carrier의 농도와 전도도의 변화가 거의 없었다. 이 축퇴된 증착막의 conduction band edge와 Fermi level의 위치가 역시 계산되었다. The electrical properties of CdS-ZnS films have been studied as a function of ZnS mixing ratio. The films were prepared by vacuum evaporation with resistor heating. Conductivity and Hall measurements performed over the temperature range 120-400K. The conductivity decredses weakly with the temperature and shows a tendency towards saturation at low temperatures. A simple relationship σ∝T^2 is found in the temperature range. The temperature dependence of carrier concentration shows that the intrinsic range in the films doped with impurities appears at 400K and the extrinsic range saturates below 400K. The band gap obtained from the temperature characteristics of the intrinsic range varies depending on the composition rate from 2.15eV to 2.46eV linearly. It is found that the mobility varies from T^(-0.3) to T^(-1.3) as the impurity concentration increases. The films with heavily doped with the impurities (5×10 exp (20)/㎤) is degenerated. The carrier concentration and the conductivity in this degenerated film is nealy independent of the temperature. The positions of corduction band edge and Fermi level in this film are also calculated.

2중 절연층구조(Zn, Cd) S : Mn EL 소자의 발광특성 Mn device with double insulating layer structure

이철준 울산과학대학 1988 연구논문집 Vol.13 No.2

고진공하에서 전자선증착기법으로 ITO 막을 입힌 유리기판 위에 Y_2 O_3-(Zn, Cd) S: Mn-Y_2 O_3 2중절 연층구조 EL 소자를 만들어 EL 특성을 측정하였다. (Zn, Cd) S: Mn 막은 증착후 진공중에서 400-500℃로 열처리하여 좋은 EL 소자를 얻을 수 있었으며, threshold와 포화전압에 따른 발광휘도의 비는 10^3 정도이다. Cds의 함량이 50% 이상일 때에는 EL 특성을 관측하기 힘들며, 가시광영역에 대한 스펙트럼은 ZnS:Mn의 경우 peak intensity가 5840A 부근에 있는 band Spectrum을 나타내고 CdS의 함량이 커지면 peak가 장파장쪽으로 이동한다. (Zn, Cd) S: Mn electroluminescence(EL) device with double insulating layer structure was prepared by electron beam evaporation technique and its emission characteristics were investigated. The structure of this device is as follows: ITO glass(transparent glass)-Y_2 O_3(insulating layer)-(Zn, Cd) S: Mn (active layer)-Y_2 O_3 (insulating layer)-Al(rear electrode). The emission spectrum of the EL device shows nearly Gaussiantype curve at room temperature and the EL peak shifts from 5840A (due to Zn S: Mn EL device) to longer wavelength due to (Zn, Cd) S: Mn EL device as CdS content of the phosphor increases.

회원사 코너 - 극동엔지니어링 주식회사

이철준,Lee, Cheol-Jun 한국하천협회 2014 하천과 문화 Vol.10 No.2

식품공업에 사용되는 효소제

이철준 한국식품산업협회 1971 좋은식품 Vol.1 No.-

샘터 산악회와의 행복한 만남

이철준 샘터사 2002 월간 샘터 Vol.33 No.4

CdS-CdSe 증착막의 광도전성

이철준 울산과학대학 1982 연구논문집 Vol.7 No.1

고진공하에서 전자선 증착 기법으로 슬라이드 유리에 CdS-CdSe 증착막을 만들어 광도전성을 측정하였다. 기판의 온도는 약 200℃로 유지하고, 증착후의 공기중에서 500℃ 정도로 열처리로 광도전성이 좋은 셀을 얻을 수 있었다. 분광 특성은 100% CdS의 경우 530㎚에서 peak값을 갖고, CdSe의 혼합비가 증가함에 따라 파장이 긴 쪽으로 이동하였다. 이들 CdS-CdSe 광도전셀의 light-to-dark 비는 약 10^4 정도였다. CdS-CdSe 박막의 결정구조는 6방정이며 기판에 수직인 방향으로 c축이 배향되어 있다. Photoconductive films of CdS-CdSe were deposited onto glass substrates by the electron beam technique under high vacuum. Postdeposition heat treatments are needed to obtain highly photoconductive films. The photoconducting properties studied include Ⅰ-Ⅴ characteristics, photosensitivity and the spectral response of the photoconductivity. Substrate temperature of about 200℃ was found to be suitable for obtaining CdS-CdSe films with faily smooth surface. The investigation of spectral response of the photoconductivity shows that the response peak for CdS is situated at 530㎚, which corresponds to the band edge of CdS. For the CdS-CdSe film, the peak shifts toward longer wavelength with the increase of the ratio of CdSe compound. Light-to-dark photoconductivity ratios up to 10^4 have been observed. The crystal structure of the CdS-CdSe film is hexagonal and the c axis is preferentially oriented perpendicular to the surface normal.

Ⅱ-Ⅵ족화합물반도체 EL 소자의 발광특성

이철준 울산과학대학 2000 연구논문집 Vol.26 No.2

In this study, Emphasis is given to II-VI thin film material such as ZnS:Mn, Zn(S,Se):Mn, (Zn,Cd)S:Mn, ZnS:TbF_3, ZnS:SmF_3, SrS:Ce,Cl ZnS:Mn, ZnS:TbF_3 and SrS:Ce, were investigated their EL characteristics. The ZnS EL device with Mn concentration of 0.5wt% and TbF_3 concentration of 2.0wt% shows strongest emission intensity It is considered the most effective luminescent center is obtained at an SmF_3 concentration of 1wt%. And the SrS:Ce,Cl with ZnS buffer layers has a maximum brightness and luminescent efficiency.

Cd (S, Se) 및 (Zn, Cd)S 증착막의 광도전성

이철준 울산과학대학 1986 연구논문집 Vol.11 No.1

고진공하에서 전자선증착기법으로 유리기판에 Cu로 활성화시킨 Cd(S, Se) 및 (Zn, Cd)S 증착막을 만들어 광도전성을 측정하였다. Cd(S, Se) 박막은 증착후 공기중에서 400-500℃로 열처리하여 광도전성이 좋은 셀을 얻을 수 있었으며, light-to-dark비는 10^3-10^4 정도이다. (Zn, Cd)S 박막의 경우 ZnS 함량이 많을수록 광도전성이 저하되며, ZnS함량이 50%이상에서는 광도전성을 관측하기 힘든다. CdS와 CdSe의 분광특성은 각각 512㎚와 697㎚에서 peak 값을 가지며 CdSe의 mole비가 커질수록 장파장쪽으로 peak가 이동된다. (Zn, Cd)S의 경우 ZnS 비율이 증가할수록 단파장쪽으로 peak가 이동되며, Cd(S, Se)보다 좁은 폭의 분광감도 범위를 갖는다. 이 광도전셀은 6방정특유의 (0002)면에 의한 강한 회절선의 peak를 보이며, 회절선에 대응하는 회절각들은 혼합비에 따라 mixed crystal로 인한 격자상수의 변화를 보여준다. This paper deals with photoconductivities of Cd(S, Se) and (Zn, Cd)S films activated by Cu. Cd(S, Se) films deposited by Electron Beam Evaporation Technique show high photosensitivity after heat treatment in a temperature range of 400-500℃ in air. The values of light to dark current ratio of the films are of the order of 10^3-10^4. In (Zn, Cd)S films prepared by the same method, the photoconductivity becomes poor and this tendancy is more prominent with greater ZnS content. The maximum peaks of spectral sensitivity in CdS and CdSe are located at 512㎚ and 697㎚, respectively and with greater mole ratio of CdSe to CdS, the peak shifts to longer wavelength and the spectral sensitivity range becomes broader. In (Zn, Cd)S films, the peak shifts to shorter wavelength as ZnS contents increases, covering rather narrow spectral sensitivity range. The X-ray analyses of diffraction patterns show that the crystal structures are hexagonal. The diffraction line of only (0002) plane can be observed, indicating that plane of the c-axis of crystal grows perpendicular to the substrate.

中國의 原油 確保戰略과 韓國의 對應方案

이철준(Lee Chual-Jun),한상옥(Han Sang-Ok) 조선대학교 지식경영연구원 2006 지역개발연구 Vol.11 No.1

This study aims to analyze the effects of the increase in Chinese oil demand and of China's oil security strategy on the oil market and to suggest korea's Countermeasures. With China's consistent economic growth, the increase in its dependence on foreign oil is said to pose a significant problem to the country in terms of its energy security. Accordingly, China is trying to develop various strategies to acquire secure oil resources. The policy that China is pursuing regarding this can be summarized as follows: 1) active development of its domestic oil resources, 2) investment in the development of overseas oil resources, 3) stabilization of oil supply, 4) increase in oil stockpiling capacity, and 5) strengthening of its resource diplomacy.