• Title/Summary/Keyword: Max Planck

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Origin of Green Emission in Extremely Pure Oligofluorene Films: Effect of Molecular Packing

  • Kang, Ji-Hoon;Shin, Na-Yool;Jo Jung-Ho;Keivanidis Panagiotis E.;Laquai Frederic;Wegner Gerhard;Yoon, Do-Y.
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.236-236
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    • 2006
  • Time-resolved photoluminescence spectroscopy measurements of oligofluorenes with various side chains were studied. With extremely pure oligofluorenes, two kinds of red-shifted green emission were observed which have different origins; aggregate formation and on-chain chemical defect. The green emission around 490 nm was largely dependent upon the intermolecular interaction of oliglfuorene molecules. Moreover, by using oligofluorene with high-order liquid crystalline phase, we observed that the green emission was strongly dependent upon the molecular packing in solid films.

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A Time to Fast, a Time to Feast: The Crosstalk between Metabolism and the Circadian Clock

  • Kovac, Judit;Husse, Jana;Oster, Henrik
    • Molecules and Cells
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    • v.28 no.2
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    • pp.75-80
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    • 2009
  • The cyclic environmental conditions brought about by the 24 h rotation of the earth have allowed the evolution of endogenous circadian clocks that control the temporal alignment of behaviour and physiology, including the uptake and processing of nutrients. Both metabolic and circadian regulatory systems are built upon a complex feedback network connecting centres of the central nervous system and different peripheral tissues. Emerging evidence suggests that circadian clock function is closely linked to metabolic homeostasis and that rhythm disruption can contribute to the development of metabolic disease. At the same time, metabolic processes feed back into the circadian clock, affecting clock gene expression and timing of behaviour. In this review, we summarize the experimental evidence for this bimodal interaction, with a focus on the molecular mechanisms mediating this exchange, and outline the implications for clock-based and metabolic diseases.

SUPERNOVA REMNANTS IN THE MAGELLANIC CLOUDS

  • BOZZETTO, LUKE M.;FILIPOVIC, MIROSLAV D.;HABERL, FRANK;SASAKI, MANAMI;KAVANAGH, PATRICK;MAGGI, PIERRE;UROSEVIC, DEJAN;STURM, RICHARD
    • Publications of The Korean Astronomical Society
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    • v.30 no.2
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    • pp.149-153
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    • 2015
  • We present an ongoing study of the complete sample of supernova remnants (SNRs) and candidates in the Magellanic Clouds. 108 objects in both Clouds are considered to be either SNR or reliable candidates. This represents the most complete sample of all known SNRs in any galaxy. It therefore allows us to study SNR population properties such as the age-diameter (Age-D) relation. Here, we show that this Age-D relation is strongly dependant on the local environment in which SNRs are residing.

Untersuchungen zur Kohlenstoffloslichkeit in Molybdan und Molybdan-Va-Metall-Legierungen

  • Klaus Schulze;Kim, Hyung-Jin;Hermann Jehn
    • Journal of the Korean institute of surface engineering
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    • v.16 no.3
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    • pp.108-123
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    • 1983
  • 순수 Mo와 Mo-Nb, Mo-Ta($\leq$10 at% Nb. Ta)합금을 1,500-2,06$0^{\circ}C$ 범위에서 탄소의 고용도를 연구하였다. 특수한 침탄방법으로 C2H2를 시편에 침탄한후 열처리하여 부분적으로 석출하거나 완전석출에 관계없는 화학적 분석방법으로 행하였다. 순수 Mo에서 최대탄소 고용도는 logCCmax = 7.02-9,490/T이다. Nb, Ta를 미량첨가하여 탄소의 최대 고용도는 Arrhenius 식을 적용할 수 없다. Nb-, Ta- 농도와 온도에 따라 Mo2C와 Nb-,Ta-를 함유한 여러 가지 탄화물상을 만들거나 $\alpha$고용체와 Mo가 포함된 NbC, TaC와 평형상태를 나타나기 때문이다. 실험온도 범위에서 Nb, Ta를 첨가량을 증가하면 탄화물 내부에 NbC, TaC로 석출된다. 고온에 용해된 a-고용체는 150-200 oK/Min으로 냉각하면 석출물은 결정입계나 결정내부에 나타난다. 순수 Mo에 Nb, Ta를 첨가하여도 경도, 파괴실험에서와 같이 인장강도는 크게 증가하지 않는다.

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Theoretical Optical Waveguide Investigation of Self-Organized Polymer Thin Film Nanostructures with Nanoparticle Incorporation

  • Lau, King Hang Aaron;Knoll, Wolfgang;Kim, Dong-Ha
    • Macromolecular Research
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    • v.15 no.3
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    • pp.211-215
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    • 2007
  • Hybrid thin film nanostructures composed of metal nanoparticles (NPs) and self-assembled polymer films with different spatial distributions of NPs were analyzed by optical waveguide spectroscopy (OWS). Specifically, the dielectric constants were calculated using effective medium theory for the incorporation of 1 vol% Au NP into the block copolymer (BCP) films having a cylindrical nanodomain morphology. Three cases were considered: uniform distribution of NPs in the film; selective distribution of NPs only in the cylindrical domains; and segregation of NPs to the center of the cylindrical domains. The optical waveguide spectra derived from the calculated dielectric constants demonstrate the feasibility of experimentally distinguishing the composite nanostructures with different inner morphologies in the hybrid metal NP-BCP nanostructures, by the measurement of the dielectric constants using OWS.

Modification of Carbohydrate Metabolism in Transgenic Potato

  • Heyer, Arnd G.
    • Journal of Plant Biotechnology
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    • v.2 no.1
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    • pp.13-19
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    • 2000
  • Carbohydrates serve three different principal functions in the metabolism of plants. They are the primary products of energy fixation, they are important transport metabolites, and they are deposited as structural or storage compounds. Modification of carbohydrate metabolism therefore covers approaches to modify yield, to change sink/source relationships and thereby alter the ratio of harvestable material, and to improve the quality of crop plants. The scope of this article is to summarize research done at the Max-Planck-Institute related to the first two fields and to present in some detail what we learned, when we established a new carbohydrate storage form in potato.

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에너지 기행 - 대한민국 청년 3인방의 독일 Max Planck IPP 방문기

  • Oh, Yeong-Seok;Lee, Won-Jae;Lee, Hyeon-Yeong
    • 핵융합뉴스레터
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    • s.48
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    • pp.22-23
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    • 2010
  • 지난 9월, 두근거리는 마음을 안고 독일행 비행기에 몸을 실은 3명의 청년이 있었다. 국가 핵융합연구소가 차세대 핵융합 전문 인력 양성이라는 목표 아래 시행한 '해외 여름학기 연수프로그램'. 국내 석박사 과정의 핵융합 인재를 대상으로 해외 핵융합 선진국의 연구기관을 직접 방문하는 이 프로그램에 지원한 오영석, 이원재, 이현영 씨가 바로 그 주인공들이다. 유럽 플라즈마 연구를 선도하는 독일의 막스 플랑크 플라즈마 물리연구소(Max Planck IPP)에서의 짧지만 잊을 수 없는 그 일주일을 되짚어 보자.

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