• 제목/요약/키워드: HOMO

검색결과 561건 처리시간 0.035초

시멘트 고결체의 양생수에 따른 강도특성 및 환경적 영향에 관한 연구 (Strength Characteristics of Solidified Cement Grout on Curing Solution and Environmental Effects)

  • 천병식;이재영;김경민
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2003년도 봄 학술발표회 논문집
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    • pp.689-696
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    • 2003
  • In this study, ordinary portland cement, slag cement and micro cement which have been used in the construction fields were evaluated for the environmental effects and compression strength characteristics for curing solution. To find the leaching of C $r^{6+}$ characteristics in cement grouts, C $r^{6+}$ content tests were performed for the raw materials(cement powder). In addition, C $r^{6+}$ leaching tests were peformed for the homo-gel samples according to change of pH and each curing solution with the deionized water and leachate. Then, the unconfined compression strength tests were peformed with the homo-gel samples and the amount of changed C $r^{6+}$ was measured by curing solution.

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Rhodamine 6G Based New Fluorophore Chemosensor Toward Hg2+

  • Son, Young-A;Park, June-Min
    • 한국염색가공학회지
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    • 제24권3호
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    • pp.158-164
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    • 2012
  • Rhodamine dyes belong to xanthene family has excellent photostability and photophysical properties. In rhodamine dyes, Rhodamine 6G and its precursors also have xanthene chromophore and it shows high fluorescent quantum yield. Rhodamine 6G derivates are simple to synthesis and its high sensitivity and water solubility are suitable as good chemosensor. In this regard, Rhodamine 6G derivates which have selectivity to specific metal cation can used to detect various heavy metal ions. In this study, rhodamine 6G derivatives were synthesized by reaction of rhodamine 6G hydrazide and glyoxal and 4-phenyl thiosemicarbazide and it showed colorimetric and fluorescence sensing toward $Hg^{2+}$ ion. This novel chemosensor was analyzed and measured on UV-Vis and fluorescence spectrophotometer. HOMO/LUMO values were also calculated by computational calculation.

지능형 생산시스템과 CAM의 지능화

  • 안중환
    • 한국정밀공학회지
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    • 제10권3호
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    • pp.21-24
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    • 1993
  • 인간을 학술용어로는 호모 사피엔스(Homo Sapiens:지성인) 또는 호모 파베르(Homo Faber:공작인)로 표현하는 것에서도 알 수 있듯이 우리 인간은 그 이유야 어쨌든 본질적으로 도구를 사용하고 물건을 만드는 능력을 가지고 있다. 그리고 물건만들기(생산) 기술은 수렵사회, 농경사회, 공업사회, 정보화사회로 사회가 바뀌는 동안 끈임없이 변화 발전해 왔다. 특히 40년대말 50년대 초에 걸쳐 개발된 컴퓨터, NC(수치제어)기 술과 70년대에 개발된 마이크로프로세서 기술은 그후의 생산기술을 획기적으로 변화시키고 말았다. 즉 설계, 가공, 조립, 검사, 보관 등 생산에 필요한 요소가능을 자동화시키고, 나아가 이들을 연결 통합하여 CAC/CAM, FMC, FMS와 같은 고도의 자동화 생산시스템이 가능하게 하였다. 그 결과 인간은 재이없고 지루한 단순 반복 작업에서 해방되어, 자동화 시스템을 프로그래밍 또는 관리. 통제하는 지적작업에 전념하게 되었고, 고품질에 싼 제품이 생산되게 되었다. 더나아서 최근에는 생산 시스템에 지능을 부여한 IMS(Intelligent Manufacturing System:지능형 생산 시스템)를 실현하고자 하는 국제 공동연구가 추진되기에 이르렀다. 이 글에서는 IMS의 모습을 잠시 살펴본 뒤 그 핵심기술의 하나인 지능형 CAM의 모습과 실현방법에 대해서 알아 보도록 한다.

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Analyses of Two Different Versions of HETCOR Techniques for Solids

  • Kim, Se-Hun;Han, Doug-Young
    • 한국자기공명학회논문지
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    • 제12권2호
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    • pp.81-88
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    • 2008
  • Solid HETCOR (Hetero-Correlation) requires homo-dipolar decoupling between proton spins during the evolution and the mixing period in 2D-NMR. There are two different ways of achieving it with pulse sequences. One is based on the multiple pulse (MP) sequence where thousands of intense radio frequency (rf) pulses are used to remove the homo-dipolar interaction between protons. The other is utilizing the so-called Lee-Goldburg (LG) off-resonance scheme where a continuous rf-irradiation is used. In this report, the advantage of one technique to the other, is analyzed. LG version is evaluated better in S/N and easier in setup procedure with the same experimental time.

전기설비용 polyethylene terephthalate의 electret 특성연구 (Electret Characteristics of polyethylene terephthalate for electret installation)

  • 국상훈;서장수
    • 한국조명전기설비학회지:조명전기설비
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    • 제10권3호
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    • pp.78-85
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    • 1996
  • 표면전위측정 수단을 이용하여 polyethylene terephthalate의 electret 구조를 해명하는 실험을 하였다. 시료에 전극을 증착하므로서 내부의 전하생성과 감쇠를 관측하였다. electret 의 기구에는 hetero charge 와 home charge가 공존하고 있으며 model로 2전하이론을 기반으로 연구하였는데 hetero charge는 쌍극자와 내부의 이온 변위로 되고 hetero charge를 형성하는 것은 외부에서 주입된 전하라고 생각된다.

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Characteristics of HOMO and LUMO Potentials by Altering Substituents: Computational and Electrochemical Determination

  • Kim, Young-Sung;Kim, Sung-Hoon;Kim, Tae-Kyung;Son, Young-A
    • 한국염색가공학회지
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    • 제20권5호
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    • pp.41-46
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    • 2008
  • Recently, computational calculation of molecular energy potentials and electrochemical reduction/oxidation behaviors are of very importance in view point of prediction of dye's properties such as energy levels and bandgaps of absorption. This can be influenced by their different constituents or substituents in chromogen molecules. Structural conformations and properties with computational modeling calculation are numerically simulated, which are fully or partly based on fundamental laws of physics. In addition, cyclic voltammetric measurement was used to obtain the experimental redox potential values, which were compared to the computed simulation values.

동품종 교배와 이품종 교배를 교번한 이중교배의 차대잠 형질에 관한 연구(II) (교미시간과 정자의 활동성이 이중교배에 미치는 영향) (Studies on the Character of Silkworm, Bombyx mori L., Which Bred from Double Copulation. (About the effect of copulating time and sperm activity in the double copulating))

  • 김윤식
    • 한국잠사곤충학회지
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    • 제6권
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    • pp.9-17
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    • 1966
  • The ratio of form and character in the text generation of silkworms which were double copulated between home race copulation and hetero race copulation in crossing with two males of different races for female(double crossing) are different according to the copulating time, copulating order and sperm activities. But the general tendencies are as follows; 1. During two hour's double copulation, sufficiently ejaculating time, the fertilization percentage of hetero lace copulation are higher than that of homo race, but in case of double copulation with plain and normal marked silkworms showed opposite results. The fertilization percentage of homo race copulation are equal or higher compare with that of hetero race copulation. 2. The form and character of the next generation were largely effected by copulating order, so the primary copulating moths are more effected in the next generation than the secondary moths. 3. The active sperms were more fertilized than non-active sperms in the double copulation.

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Distinct Mechanisms of DNA Sensing Based on N-Doped Carbon Nanotubes with Enhanced Conductance and Chemical Selectivity

  • Kim, Han Seul;Lee, Seung Jin;Kim, Yong-Hoon
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.415.1-415.1
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    • 2014
  • Carrying out first-principles calculations, we study N-doped capped carbon nanotube (CNT) electrodes applied to DNA sequencing. While we obtain for the face-on nucleobase junction configurations a conventional conductance ordering where the largest signal results from guanine according to its high highest occupied molecular orbital (HOMO) level, we extract for the edge-on counterparts a distinct conductance ordering where the low-HOMO thymine provides the largest signal. The edge-on mode is shown to operate based on a novel molecular sensing mechanism that reflects the chemical connectivity between N-doped CNT caps that can act both as electron donors and electron acceptors and DNA functional groups that include the hyperconjugated thymine methyl group[1].

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폴리프로필렌 이산화티타늄 첨가 폴리플로필렌의 이성분 복합섬유의 물리적 성질 (physical Properties of Sheath-Core Fibers of Polypropylene and Titanium Dioxide Filled Polypropylene)

  • 한성수
    • 유변학
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    • 제6권2호
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    • pp.147-156
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    • 1994
  • 폴리프로필렌 이산화티타늄 첨가 폴리프로필렌을 심초형 복합 방사하여 첨가제를 섬유의 중심부분, 또 표면부분에 차별분포시켰다. TiO2의 함량이 증가함에 따라 점도(η)와 저장탄성계수(G')는 증가하였다. 전자현미경으로 파단면의 모폴로지를 관찰한 결과 TiO2와 함량이 증가함에 따라 감소하는 경향을 보였다. TiO2의 함량 증가에 따라 강력, 절단신도, 그리고 탄성계수는 감소하였다. 복합방사한 섬유의 TiO2 함량이 2% 미만일 때는 homo PP 보다 강력이 좋아졌다. 복합 섬유의 탄성계수는 중심부에 homo PP가 분포한 경우가 더 컸 고 강력과절단 신도는 중심부에 filled PP가 분포한 경우가 더 컸다.

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