치암중초약의 돌연변이유발 및 돌연변이유발 억제효과

이현철 대한미생물학회 1987 大韓微生物學會誌 Vol.22 No.2

Ten species of herbae, which have been used to treat cancers in Chinese medicine, were tested to investigate their mutagenieity or antimutagenicity in S. typhimurium TA97, TA98, TA100, TA1S35, and TA1538. Scolopendra centipede was weakly active in reversion of the frameshift mutation in S. typhimurium TA97 strain and the base-pair substitution in TA100 and TA1535 strains. Other herbae such as Coix lachryma, Dianthus superbus, Tricanthoshse kirilowii, Eupatorium formo- sanum, Lithospermum erythrorliizon, Arisaema japonicum, Curcuma aedoaria, Helicteres angustifolia, and Euonymus sieboldianus did not show any of the mutagenic potential, regardless of the metabolic activation with rat hepatic microsomal fraction. Dianthus superbus, Eupatorium formosanum, and Euonymus sieboMianus exhibited suppressive activities on microbial mutagenesis of N-methyl-N-nitrosoguanidine, a basepair substitution mutagen, in TA1535 and TA10G tester strains. The antimutagenic activities of Dianthus superbus and Euonymus sie- boldianus appeared to be dose-dependant.

"그들은 무엇을 요구하고 있는가?" : 한국 내 코로나 블루(Corona Blue) 청소년의 요구 분석

이현철 고신신학회 2021 고신신학 Vol.- No.23

"그들은 무엇을 요구하고 있는가?" : 한국 내 코로나 블루(Corona Blue) 청소년의 요구 분석

후속열처리 및 고온고습 조건에 따른 Cu 배선 확산 방지층 적용을 위한 ALD RuAlO 박막의 계면접착에너지에 관한 연구

이현철,정민수,배병현,천태훈,김수현,박영배,Lee, Hyeonchul,Jeong, Minsu,Bae, Byung-Hyun,Cheon, Taehun,Kim, Soo-Hyun,Park, Young-Bae 한국마이크로전자및패키징학회 2016 마이크로전자 및 패키징학회지 Vol.23 No.2

The effects of post-annealing and temperature/humidity conditions on the interfacial adhesion energies of atomic layer deposited RuAlO diffusion barrier layer for Cu interconnects were systematically investigated. The initial interfacial adhesion energy measured by four-point bending test was $7.60J/m^2$. The interfacial adhesion energy decreased to $5.65J/m^2$ after 500 hrs at $85^{\circ}C$/85% T/H condition, while it increased to $24.05J/m^2$ after annealing at $200^{\circ}C$ for 500 hrs. The X-ray photoemission spectroscopy (XPS) analysis showed that delaminated interface was RuAlO/$SiO_2$ for as-bonded and T/H conditions, while it was Cu/RuAlO for post-annealing condition. XPS O1s peak separation results revealed that the effective generation of strong Al-O-Si bonds between $AlO_x$ and $SiO_2$ interface at optimum post-annealing conditions is responsible for enhanced interfacial adhesion energies between RuAlO/$SiO_2$ interface, which would lead to good electrical and mechanical reliabilities of atomic layer deposited RuAlO diffusion barrier for advanced Cu interconnects. 차세대 반도체의 초미세 Cu 배선 확산방지층 적용을 위해 원자층증착법(atomic layer deposition, ALD) 공정을 이용하여 증착한 RuAlO 확산방지층과 Cu 박막 계면의 계면접착에너지를 정량적으로 측정하였고, 환경 신뢰성 평가를 수행하였다. 접합 직후 4점굽힘시험으로 평가된 계면접착에너지는 약 $7.60J/m^2$으로 측정되었다. $85^{\circ}C$/85% 상대습도의 고온고습조건에서 500시간이 지난 후 측정된 계면접착에너지는 $5.65J/m^2$로 감소하였으나, $200^{\circ}C$에서 500시간 동안 후속 열처리한 후에는 $24.05J/m^2$으로 계면접착에너지가 크게 증가한 것으로 평가되었다. 4점굽힘시험 후 박리된 계면은 접합 직후와 고온고습조건의 시편의 경우 RuAlO/$SiO_2$ 계면이었고, 500시간 후속 열처리 조건에서는 Cu/RuAlO 계면인 것으로 확인되었다. X-선 광전자 분광법 분석 결과, 고온고습조건에서는 흡습으로 인하여 강한 Al-O-Si 계면 결합이 부분적으로 분리되어 계면접착에너지가 약간 낮아진 반면, 적절한 후속 열처리 조건에서는 효과적인 산소의 계면 유입으로 인하여 강한 Al-O-Si 결합이 크게 증가하여 계면접착에너지도 크게 증가한 것으로 판단된다. 따라서, ALD Ru 확산방지층에 비해 ALD RuAlO 확산방지층은 동시에 Cu 씨앗층 역할을 하면서도 전기적 및 기계적 신뢰성이 우수할 것으로 판단된다.

Electrochemical performance of anthracite-based activated carbon eletrodes for EDLC

이현철,심왕근,문희 한국공업화학회 2014 한국공업화학회 연구논문 초록집 Vol.2014 No.0

탄산화법을 이용한 용존 비소 제거에 관한 연구

이현철,민경원,서의영 한국자원공학회 2013 한국자원공학회지 Vol.50 No.1

탄산화법은 침강성탄산칼슘을 제조하는 방법의 하나로 Ca(OH)2, CO2, 물을 반응시켜 탄산칼슘을 제조하는 방법을 말한다. 본 연구에서는 휴 · 폐광산 광산배수 및 지하수 등에 존재하는 비소를 제거하기 위한 방법으로 탄산화법을 적용하여 실험을 실시하였다. 1차 실험결과, As(III)는 최대 26.5% 제거되었고, As(V)는 최대 90.6%까지 제거되었다. 소석회 투입량을 증가시켜 실시한 2차 실험 결과, As(III)는 최대 38.7%, As(V)는 최대 95.1% 제거되었다. 반응 용액의 최종 pH는 6.0~6.5 범위로 수질기준을 만족하였고, Eh는 -330 mV~+50 mV 범위를 나타냈다. 2차 실험의 반응생성물에 대한 XRD 분석을 실시한 결과 방해석 peak가 확인되었고, SEM 분석을 통해 육면체 형태의 결정을 갖는 방해석임을 확인하였다. 또한 EDS 스캐닝을 통해 As(III) 0.04% 이하, As(V) 0.06~0.07%가 생성된 방해석 표면에 존재하는 것으로 확인되었다. 결과적으로 탄산화법에 의한 비소제거는 As(III)의 경우 비효율적인 것으로 나타났으며, As(V)의 경우 효율적인 제거가 가능한 것으로 나타났다. The carbonation process, one of the calcium carbonate precipitating methods, consists of a reaction of Ca(OH)2, CO2, and water. In this study, laboratorial tests were conducted to remove the arsenic from the abandoned mine drainage and ground water using the carbonation process. As (III) and As (V) were removed up to 26.5% and 90.6%, respectively in the preliminary test and up to 38.7% and 95.1%, respectively in the second test with an increased amount of hydrated lime. Final pH’s of reacted solutions were 6.0 to 6.5, which are satisfying with the water standard and Eh’s range between -330 mV and +50 mV. Calcite peak was observed in the reaction precipitates of the follow-up test by XRD analysis and also, hexahedral structures of calcite crystals were identified by SEM analysis. As (III) and As (V) were detected in the range of below 0.04% and 0.06~0.07%, respectively by EDS scanning. Consequently, the carbonation pr ocess can remove aqueous As (V) efficiently, but As (III) insufficiently.

Remission in models of type 1 diabetes by gene therapy using a single-chain insulin analogue

이현철,김수진,김경섭,신항철,윤지원 한국생화학분자생물학회 (구 한국생화학회) 2001 생화학분자생물학회 소식 Vol.21 No.1

A Qualitative Approach to Ministries and Church Education in Multicultural/ethnic Churches in the U.S.: From “Melting Pot” to “Salad Bowl”

이현철 한국기독교교육학회 2010 기독교교육논총 Vol.25 No.-

The purpose of this study is to help find effective ways of educating congregations in the emerging multicultural ambience of South Korea by studying healthy and functional multiethnic churches in the U.S., particularly, focusing on their church education and ministries through qualitative research methods. The participants of this study are selected from the leadership of three local churches in Massachusetts, U.S. and five of eight interviewees, in charge of multicultural churches, were selected for analysis based on how well they representedthe range of experiences across the sample. Through qualitative approaches, we have discovered five dimensions of the successful multi-ethnic church in the U.S.: 1) a welcoming atmosphere, 2) empathy, 3) cultural sensitivity, 4) a willingness to change old ways, and 5) program diversity. The churches showing these characteristics werenot only healthy and functional, but also experiencing growth. Additionally, we were able to come up with a structural concept based on the abovementioned five characteristics of the successful multi-ethnic church, as hospitality, humility, openness, flexibility, and diversity. These are qualities that appear to provide the multicultural/ethnic church a solid foundation for helping congregants to become mature in the faith.

평면형 Bi-Sb 다중접합 열전변환기의 특성

이현철,유호종,김진섭,함성호,신장규,이종현,이정희,권성원,박세일 경북대학교 센서기술연구소 1997 센서技術學術大會論文集 Vol.8 No.1

A planar Bi-Sb multijunction thermal converter for the precise measurements of ac voltage and current has been fabricated and its characteristics was discussed. In order to convert ac power into heat, a bifilar thin film Pt-heater, which could cancel its Thomson and Peltier effects, was prepared on the Si_(3)N_(4)/SiO_(2)/Si_(3)N_(4) diaphragm for the thermal isolation between heater and silicon substrate. To convert the temperature or the heat generated by the heater into dc voltage and current, hot and cold junctions of the Bi-Sb thermopile, which has a large difference in Seebeck coefficients, were formed on the dielectric diaphragm and the silicon substrate, respectively. The respective thermal sensitivity of the thermal converter with a bifilar heater was about 10.1 mV/mW and 14.8 mV/mW in the air and vacuum, which is about eight times higher than that of commercial 3-dimensional thermal converter. In the case of ac 2 V-input voltage, the ac-dc voltage transfer difference was about ±2.0 ppm, and in the case of ac 10 mA-input current, the ac-dc current transfer difference was about ± 0.6 ppm, in the frequency range from 10 Hz to 10 kHz.

전기절도에 관한 ‘썰’에 대한 소고

이현철 대한전기학회 2018 전기의 세계 Vol.67 No.6

FSP in Written English : O'Henry 의 작품을 통한분석 with special reference to O'Henry's 'After Twenty Years'

이현철 동아대학교 문과대학 영어영문학과 1987 동아영어영문학 Vol.3 No.-

This study is to examine the relevance of FSP to English, written English in particular. For this purpose, I selected a story of 0'Henry, the famous American Writer Every sentence in the text is checked through devices of which a number are related to the theory of FSP. They are roughly initial group of sentence, theme and rheme, old, and new information, CD degree and marked and unmarked word order, etc. These devices enable us to check whether or not FSP is a relevant theory for written English.The data in this paper show that more than 70% of sentences in the text are relevant to FSP. The initial group of 46 out of 70% sentences are more or less related to the previous sentence. They are, thus, old in terms of information. The initial position of 24 sentences is occupied by new information but the degree of CD is low.