치환된 페로브스카이트형 복합산화물 $LaMn_{1-x}Cu_xO_3$의 환원반응성

황호순,최혁,박일현,Hoo-Soon Hwang,Huek Choi,Il-Hyun Park 대한화학회 1993 대한화학회지 Vol.37 No.2

부분 치환된 LaCoO_3 perovskite형 복합산화물의 환원성

황호순 성균관대학교 기초과학연구소 1995 論文集 Vol.46 No.1

Nonstoichiometry, thermal stability and reactivity in static H_2 atmosphere of partially substituted perovskite-type LaCoO_3 mixed oxides were investigated by means of TPR and X-ray diffraction. The XRD and TPR analysis showed hexagonal structures of single phase perovskite. LaCoO_(3.0) a=5.436, c=13.095; La_(0.9)Sr_(0.1)CoO_(3.0) a=5.445, c=13.126; LaCo_(0.9)Cu_(0.1)O_(3.0) a=5.445, c=13.119; La_(0.9)Sr_(0.1)Co_(0.9)Cu_(0.1)O_(3.0) a=5.455, c=13.158. The reduction reaction of unsubstituted LaCoO_3 were two stages but each site substituted oxides showed three stage reaction. This means that the last reduction stages were induced by substituents(Sr, Cu). According to the kinetic analysis for the first reduction stages, B-site substituted LaCo_(0.9)Cu_(0.1)O_3 showed the lowest activation energy.

이중성을 내포하는 Frost와 그의 시에 대한 연구

黃皓順 서울市立大學校 1983 論文集 Vol.17 No.-

It has been said that in Robert Frost there is quite a remarkable difference between the real Frost and the public Frost he assumes. The long period of forty years during which he has experienced during his life may account for his multiple attitudes he takes on or the discrepancy he shows since he was engaged in different kinds of occupation, teaching, writing poetry, and working as a farmer. Though he spent more time teaching poetry at universities and meeting not farmers but urban literary persons, he must have liked to appear as a farmer poet of New England, enjoying the fame critics have given mistakenly. As a poet has every right to be estimated by his best, Frost shouldn'd be called just a simple farmer poet. He wrote many poems describing the country scenes of New England which could be read and enjoyed by simple readers but in his simplicity we can not avoid feeling something more, "clarification of life" in his own word. The only diference we find in him from other modern poets can be said to be that Frost wrote many subtle poems, "quasi-moral" and "quasi-religious" enough, which even most common readers who are not sensitive enough to trace his "clarification of life" and are apt to miss their real meanings of can enjoy. Frost has enjoyed the "fame" of the New England farmer poet and he would like to profess to be that depicting successfuly the scenery in the country but in his "better" poems we can discover characteristics of complicated modern poems whose scenes are usually located in cities. Therefore Frost is not a simple New England Yankee farmer poet whose sensibility is modern and complicated enough to write quasi-moral and quasi-religious poems, whose way of thinking and expression is subtle and evasive enough to be hidden behind their simple appearances if we do not exercise our imagination at best.

Bordetella bronchiseptica의 alcaligin siderophore 생합성 유전자인 alcA에 관한 연구

황호순,김영희,김삼웅,유종언,유아영,강호영,이태호,Hwang, Ho-Soon,Kim, Young-Hee,Kim, Sam-Woong,Yu, Jong-Earn,Yoo, Ah-Young,Kang, Ho-Young,Lee, Tae-Ho 한국생명과학회 2006 생명과학회지 Vol.16 No.7

돼지 위축성 비염과 개의 kennel cough의 원인균인 B. bronchiseptica는 각 숙주의 상부 호흡기관의 점막에 집락을 형성하는 병원균으로서 철이 부족한 환경에서 hydroxamate type의 alcaligin이 라는 siderophore를 생산한다. Alcaligin의 생합성에 관련하는 구조유전자 중 alcA 유전자의 기능을 밝히고자 alcA 결손돌연변이주 구축을 통하여 확인하였다. alcA 유전자 결손 돌연변이를 위해 0.6 kb alcA 5' flanking DNA와 0.7 kb alcA 3' flanking DNA fragment들을 pCP1.11을 주형으로 하여 PCR법으로 증폭한 후, 5' flanking과 3' flanking DNA가 연결된 재조합 suicide vector pDMl을 구축하여 세포 접합을 통해 B. bronchiseptica로 도입시켰다. 도입된 pDM1으로부터 allelic exchange법에 의해 alcA 유전자가 결손된 돌연변이주 B. bronchiseptica H1을 얻을 수 있었다. B. bronchiseptica H1은 야생형인 B. bronchiseptica에 비하여 alcaligin siderophore를 거의 생성하지 못하였다. alc 오페론 중 promoter와 alcA 유전자만을 가지는 재조합 플라스미드를 B. bronchiseptica Hl에 도입하였을 때 alcaligin siderophore의 생산이 회복됨을 확인할 수 있었다. 이상의 결과로부터 alcA 유전자가 alcaligin 생합성에서 매우 중요한 역할을 수행하는 것을 알 수 있었다. Bordetella bronchiseptica, the agent of swine atrophic rhinitis and kennel cough in dogs, is a mucosal pathogen and produces the hydroxamate type alcaligin siderophore under iron-limited conditions. Genes involved in alcaligin siderophore biosynthesis are contained in an alcABCDE operon. In order to provide direct evidence for the role of AlcA in alcaligin biosynthesis, we needed a B. bronchiseptica mutant carrying alcA gene deletion. A 0.6 kb alcA 5'-flanking and 0.7kb 3'-flanking DNA fragments were PCR amplified with the use of pCP1.11 as a template DNA. The 5'-and 3'-flanking DNA fragments were joined in a suicide plasmid, resulting in a recombinant suicide plasmid pDM1. After introduction of pDM1 into B. bronchiseptica by conjugation, the allelic exchange technique was performed and a B. bronchiseptica alcA deletion mutant, named B. bronchiseptica H1, was obtained. The mutant strain produced reduced amount of siderophore as expected. When a plasmid containing complete alcA gene was transformed back into the mutant, the complemented mutant recovered ability of siderophore production. These results indicated that AlcA is one of essential components for the alcaligin siderophore biosynthesis. The mutant strains obtained in this study will be used in the further studies for the biochemical function of AlcA.

실락원에 나타난 John Milton의 인본주의 고찰

황호순 서울市立大學校 1991 論文集 Vol.25 No.-

Pradise Lost still seems to be commanding even those readers who had lost their interests in ideas and beliefs on which Milton's poetry is based. Even the 20th century readers who have nearly lost their concern in God can not ignore or escape the attraction to Paradise Lost in which the poet proclaimed that his purpose is not "monuments to dead ideas" despite all those archaic words, structures and those seeminly out-of-date ideas and beliefs. One of the reasons modern readers still enjoy the old world of Paradise Lost is its christian humanism. Christianity and humanism are very paradoxical in every way. But Milton has often been called as a poet of christian humanism. Some critics such as william Blake and William Empson wrote that Milton's God is depicted to be more wicked than his Satan. The writer tried to prove that Milton is, conscious or unconscious, not responsible for the fact but for the reader's attitude or misunderstanding about Milton's Christian humanism. In Milton's Paradise Lost, man is the centre point of the universe in many ways and Milton's idea about man-made city is contrasted with that of the kingdom of God. The symbol of man-made city is Pandemonium, the inhabitants of which are the demons who are the angels expelled by Christ because of their rebellion in heaven but their words and behabiours or actions are very humanistic and rational and even very heroic and they resemble those of most of the heroes and tyrants in human history. Some of them are very attractive to human beings. That is one of the reason why Milton's Satan has been so heroic to many readers for a long period but they are the demons and most of the readers know they shouldn't like to follow the examples. To avoid that kind of misunderstandings in proper appreciation of Paradise Lost, to become his "fit audience though few" we must understand Milton's idea or attitude about evil. Milton must have thought that evil is the very rebellion against God Himself and without this acquiescence of the sovereignty of God man cannot be man above an animal. This is why he has been called a Christian poet who accepted the Christian tradition of his age. Another attitude we should assume to understand Paradise Lost is that as Pardise Lost is about God, angels, demons and Christ before incarnation which we human beings can not grasp or see or feel, the reader should have some sense of transcendence, for which Milton employed a narrator who helps them to follow his work. Readers' rational minds or rationalism must be far from following Milton's meaning.

전기로 분진과 압연 Scale의 환원 및 탄화거동

황호순,정우창,정원섭,정원배,Hwang Ho-Sun,Chung Uoo-Chang,Chung Won-Sub,Chung Won-Bae 한국자원리싸이클링학회 2003 資源 리싸이클링 Vol.12 No.5

전기로에서 발생하는 분진과 압연스케일의 재활용을 위하여 전기로의 철원과 열원을 동시에 사용할 수 있는 탄화철 제조가 필요하다. 이를 위한 기초 자료를 확보하기 위하여 전기로 분진과 압연스케일의 환원거동과 탄화 거동을 조사하였다. $650^{\circ}C$ 이하의 온도에서 일산화탄소 100%로 탄화를 시키면 유리탄소는 생성되지 않으면서 세멘타이트보다 탄소함량이 더 높은 탄화철(약 9wt% C)을 생성할 수 있었다. 전기로 분진의 환원에 필요한 탄재의 양은 이론 탄재양의 약 1.2배, 그리고 환원온도는 $900^{\circ}C$가 가장 적당하였다. 압연 스케일의 환원온도는 $1000^{\circ}C$가 가장 적당하였다. 전기로 분진 및 압연 스케일의 탄화속도는 압연 스케일의 경우가 모두 빠르게 나타났다. 그리고 슈퍼탄화철의 성분은 대부분 $Fe_2$C이었다. To be recycled iron and heat source in EAF, EAF dust and mill scale generated from steelmaking plant should be made to iron carbide. Behavior of reduction and carburization in EAF dust and mill scale is studied to get fundamental data. EAF dust and mill scale are carburized at $650^{\circ}C$ by 100% CO gas. The carbon content of iron carbide(about 9 wt,% C) is higher than that of cementite without free carbon. The 1.2 times of calculated carbon content is suitable for reduction of EAF dust. The reduction temperature is appropriate to $900^{\circ}C$ in EAF dust and $1000^{\circ}C$ in mill scale. The carburization rate of mill scale are faster than those of EAF dust. The composition of super iron carbide is almost $Fe_2$C.

직장인의 스트레스 해소를 위한 건강 호흡법

황호순,Hwang, Ho-Sun 대한산업보건협회 2000 산업보건 Vol.145 No.-

입도분포가 넓은 분철광석의 탄화특성

황호순,정우창,정원섭,정원배,Hwang Ho-Sun,Chung Uoo-Chang,Chung Won-Sub,Chung Won-Bae 한국자원리싸이클링학회 2003 資源 리싸이클링 Vol.12 No.5

넓은 입도분포를 가지는 헤마타이트 철광석을 사용하여 $H_2$ 및 $H_2$-CO 혼합가스 분위기에서 환원 및 탄회특성에 대하여 고찰하였다. 환원에 의한 활성화에너지 값은 약 20kJ/mol 였다. 환원 및 탄화단계에서 무게변화는 환원단계에서는 약 28% 감소하였고, 탄화단계에서는 약 5%증가하였다. 이는 이론 계산식에 의한 값과 거의 일치하였다. 온도, 입도 및 가스비($_H2$/CO=1~5 범위)에 따른 탄화속도는 온도가 낮을수록 입자가 작을수록 그리고 가스비가 작을수록 탄화속도가 증가하였다. 또한 $H_2$의 가스비($H_2$/CO=1)가 낮을 때는 유리카본(C, free carbon)이 발생하였다. 수소가스를 혼합하였을 경우가 탄화속도는 증가하였으나, 수소분율에 비례하여 증가하지는 않았다. 혼합가스 중 수소분율($X_{H2}$ )이 0.5일 때 ($H_2$/CO=1) 탄화속도가 최대였다. 이때 수소가 탄화철 생성과정에 있어서 촉매역할을 한 것으로 추정된다. Characteristics of reduction and carbidization for hematite ore with a wide size range have been investigated at high temperature(590∼64$0^{\circ}C$) under $H_2$ and $H_2$-CO gas mixtures. The apparent activation energy for reduction of hematite ore with H2 gas was found to be 20 kJ/mol. The weight loss by reduction was about 28% md the weight gain by carbidization was about 5%. The measured values of weight change were compared with those calculated from equation (3) & (5) and fairly good agreement was obtained. The rate of carbidization was increased with an decrease in temperature, particle diameter and gas ratio($H_2$/ CO). The free carbon was increased with decrease in gas ratio($H_2$/ CO). The rate of carbidization was increased with mixing of $H_2$ gas but this effect was not proportional to fraction of $H_2$ gas. It was also found that the rate of carbidization was the maximum in the $H_2$ gas fraction of 0.5. It is considered that $H_2$ plays a part as a catalyst for formation of iron carbide($Fe_3$C).

고온 산화물 초전도체의 선재 (線材) 제조

황호순,최성조 대한금속재료학회 1988 대한금속재료학회 학술대회 개요집 Vol.1988 No.1

밀턴의 한계 : 그의 사상과 신학을 중심으로

黃晧順 서울市立大學校 1994 論文集 Vol.28 No.-

After surveying the doctrine of accommondation, the Platonic theory of Ideas (dualism), and Christian humanism which can be traced in his imagery of light, they are of some help to conclude that Milton's theoretic philosophy and theology have had much to do with his poetic techniques and imagery in describing his invisible worlds and background, fulfilling his planned hopes along with his reader's expectations. As some critics thought of Milton's hopes as impossible, Milton himself agreed to their ideas to some extent that the heavenly characters or events are very unrealistic and nearly impossible to describe and therefore it is better to leave them alone, unexpressed but Milton didn't succumb himself to the difficulties nearly all human beings would like to avoid or deny. He managed to overcome those impossible difficulties through the aids of various strands of philosophy and literary theory, which correspond and reinforce one another to a remarkable extent in practising his poetic techniques. All of the theoretic aspects provide a foundation for a portrayal of transcendental or supernatural characters, events, and even the heavenly wars in physical, human terms. At the same time, they do not minimize the very real differnece between the visible and invisible worlds, and they show that the transcendental vision or otherness is, in important ways, not directly accessible to human experience. An awareness of the theoretic background is helpful not only in establishing theoretic ideas with which Milton composed his Paradise Lost and with which the reader of his generation interpreted the poem, but also in suggesting profitable critical approaches to Paradise Lost for modern readers. The theoretic background broadens expectations or possibility and fruits of his success which the poem accomplishes.