• 제목/요약/키워드: ordered structure

검색결과 385건 처리시간 0.033초

The Interfacial Electronic Structure of Organic-organic Heterojunction: Effect of Molecular Orientation

  • 조상완
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.114.2-114.2
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    • 2014
  • The orientation of the constituent molecules in organic thin film devices can affect significantly their performance due to the highly anisotropic nature of ${\pi}$-conjugated molecules. We report here an angle dependent x-ray absorption study of the control of such molecular orientation using well-ordered interlayers for the case of a bilayer heterojunction of chloroaluminum phthalocyanine (ClAlPc) and C60. Furthermore, the orientation-dependent energy level alignment of the same bilayer heterojunction has been measured in detail using synchrotron radiation-excited photoelectron spectroscopy. Regardless of the orientation of the organic interlayer, we find that the subsequent ClAlPc tilt angle improves the ${\pi}-{\pi}$ interaction at the interface, thus leading to an improved short-circuit current in photovoltaic devices based on ClAlPc/C60. The use of the interlayers does not change the effective band gap at the ClAlPc/C60 heterointerface, resulting in no change in open-circuit voltage.

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Immunofluorescence Localization of Schizosaccharomjyces pombe $cdc103^{+}$ Gene Product

  • Kim, Hyong-Bai
    • Journal of Microbiology
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    • 제34권3호
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    • pp.248-254
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    • 1996
  • $cdc103^+$ gene in Schizosaccharomyces pombe which is similar to the CDC3 gene in Saccharomyces cerevisiae was cloned and sequenced. Comparison of the predicted amino acid sequences of $cdc103^+$ and CDC3 revealed that they share significant similarity (43% identity and 56% identity or similarity) to each other. The gene product of CDC3 in S. cerevisiae is known to be a highly ordered ring of filaments that lies just inside the cytoplasmic membrane in the region of the mother-bud neck. In order to characterize the gene product of $cdc103^+$ in Schizosaccharomyces pombe, fusion proteins were used to generate the polyclonal antibodies specific for the gene product (cdc103p). In immunofluorescence experiments, these antibodies decorate the region of the septum formation as a double ring structure late in the cell division cycle.

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Effect of Nickel Oxide on Hydrogen Storage Behaviors of Mesoporous SBA-15

  • 이슬이;박수진
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2009년도 추계학술대회 논문집
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    • pp.231-231
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    • 2009
  • In this work, we prepared the Ni-loaded porous SBA-15 (SBA-15) by a depositionprecipitation (D-P) method, in order to enhance the hydrogen storage capacity. The structure and morphology of the Ni/SBA-15 were characterized by X-ray diffraction (XRD) and field emission transmission electron microscopy (FE-TEM). The results showed that, at the Ni loading used at the DP times in the range of 0-120 min, SBA-15 preserved the well-ordered hexagonal porous arrangement. The textural properties of the Ni/SBA-15 were analyzed using N2 adsorption isotherms at 77 K. Specific surface area and mesopore volume of the samples were determined from the Brunauer-Emmett-Teller (BET) equation and Barrett-Joiner-Halenda (BJH) method, respectively. The hydrogen storage capacity of the Ni/SBA-15 was evaluated at 298 K/10 MPa. The hydrogen storage capacity of the Ni/SBA-15 was increased in accordance with Ni content. Consequently, it was found that the presence of Ni on mesoporous SBA-15 created hydrogen-favorable sites which enhanced the hydrogen storage capacity by spillover effect.

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Designing an Inventory Model of Parallel-Type Distribution System

  • Kwon, Hee Chul;Kim, Man Shik
    • 품질경영학회지
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    • 제17권1호
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    • pp.11-18
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    • 1989
  • A one-upper level warehouse n-Iower level retailer inventory distribution model is discussed. This paper presents the parallel-type inventory structure using an order-up-to-level invertory control system for analyzing the approximation of the expected units back ordered and the measure of service. We find that the total expected backorder units in system can substitute the expected back orders in the last two periods for the expected back orders in total periods. The rate of total expected back orders which is the measure of disservice, is given by dividing the improved units of total expected backorder into the total demand during an order cycle. The average annual total cost in system is obtained by considering the results, but from the viewpoint of this study the cost analysis is not described.

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주상복합건축물의 심의평가에 관한 연구 -서울시 건축(1)심의를 중심으로 - (A Study on the Architectural Evaluation for the Commercial-Residential Complex - Focused on the Seoul Building Design Review -)

  • 조자연
    • 한국주거학회논문집
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    • 제17권2호
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    • pp.143-150
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    • 2006
  • In this Study, it was investigated what the critical elements of the Architectural Review by the Seoul Building Design Committee were. The critical elements selected by the members of committee were systematically analyzed. They were based on the 169 cases reviewed by the Building Design Committee. The committee consists of Professors, famous architects, architectural experts and official members. Thus, the critical elements selected by the committee can be regarded as the important criteria for the forthcoming architectural reviewing process. The critical elements selected by 960 members of the committee were classified by the frequency. The results in this study showed that the critical elements were ordered as follows: (1)floor plan, (2)landscape gardening, (3)form, (4)open space, (5)structure, (6)plan for preventing disasters, (7)circulation for men and cars, (8)facilities, (9)parking, (10)revision of drawings and documents. These criteria of the architectural evaluation established by the Seoul Building Design Committee can be applied to the fundamental preparation of the architectural review.

Synthesis and Characterization of Co-Surfactant Templated Mesoporous Materials with Enhanced Hydrothermal Stability

  • Kim Geon-Joong;Kim Hyun-Seok;Ko Yoon Soo;Kwon Yong Ku
    • Macromolecular Research
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    • 제13권6호
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    • pp.499-505
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    • 2005
  • Ordered mesoporous materials with a hydrothermally-stable, protozeolitic framework were prepared by exploring the direct conversion of inorganic species based on co-surfactant templating systems. To confer hydrothermal stability on the mesoporous aterials, the organic-inorganic hybrids were heat-treated in strongly basic media. Co-surfactant templating systems of cetyltrimethylammonium bromide [$C_{16}H_{13}(CH_{3})_{3}$NBr, CTAB] with 1,3,5-trim­ethylbenzene (TMB) or a nonionic block copolymer of poly(ethylene oxide )-b-poly(propylene oxide )-b-poly(ethyl­ene oxide) ($EO_{20}PO_{70}EO_{20}$) were employed to improve the hydrothermal stability of the organic-inorganic self-assembly during the solid rearrangement process of the inorganic species. The mesoscopic ordering of the pore structure and geometry was identified by X-ray diffraction, small angle neutron scattering and electron microscopy.

Multiple-Layered Colloidal Assemblies via Dipping Method with an External Electric Field

  • Im, Sang-Hyuk;Park, O-Ok;Kwon, Moo-Hyun
    • Macromolecular Research
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    • 제11권2호
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    • pp.110-114
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    • 2003
  • When using the dipping method for crystal formation, mono-layered colloidal crystal structures depend upon the lift-up rate of a glass substrate. The mono-layered colloidal crystals showed the highest quality when the glass substrate was raised at a rate of 3 mm/min at 25 $^{\circ}C$ in a 1 wt% polystyrene colloidal suspension (ethanol medium). In addition, in order to obtain multiple-layered colloidal crystals, an external electric Held was introduced. Multiple-layered colloidal crystals were successfully obtained via this method. The colloidal particles were well ordered over large areas and assembled into a homogeneous structure.

Reduction Behaviors of Nitric Oxides on Copper-decorated Mesoporous Molecular Sieves

  • Cho, Ki-Sook;Kim, Byung-Joo;Kim, Seok;Kim, Sung-Hyun;Park, Soo-Jin
    • Bulletin of the Korean Chemical Society
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    • 제31권1호
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    • pp.100-103
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    • 2010
  • In this study, NO reduction behaviors of copper-loaded mesoporous molecular sieves (Cu/MCM-41) have been investigated. The Cu loading on MCM-41 surfaces was accomplished by a chemical reduction method with different Cu contents (5, 10, 20, and 40%). $N_2/77$ K adsorption isotherm characteristics, including the specific surface area and pore volume, were studied by BET's equation. NO reduction behaviors were confirmed by a gas chromatography. From the experimental results, the Cu loading amount on MCM-41 led to the increase of NO reduction efficiency in spite of decreasing the specific surface area of catalysts. This result indicates that highly ordered porous structure in the MCM-41 and the presence of active metal particles lead the synergistical NO reduction reactions due to the increase in adsorption energy of MCM-41 surfaces by the Cu particles.

Hexagonal to Cubic Phase Transition in the $D_2O$-Induced Reverse Micellar Solution of a PEO-b-PPO-b-PEO Block Copolymer

  • Kim, Do-Hyun;Ko, Yoon-Soo;Kwon, Yong-Ku
    • Macromolecular Research
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    • 제16권1호
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    • pp.62-65
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    • 2008
  • The morphology of the $D_2O$-induced reverse micellar structure of an amphiphilic block copolymer of poly( ethylene oxide )-b-poly(propylene oxide )-b-poly( ethylene oxide )($EO_{76}PO_{29}EO_{76}$) was investigated in hydrophobic media by small angle neutron scattering (SANS). Increasing $D_2O$ in the styrene/divinylbenzene solution of $EO_{76}PO_{29}EO_{76}$ led to a change in morphology of the reverse micelles from a short range ordered molecular aggregate to a hexagonally arranged micelle, and further to a spherical micelle.

A Study of Co, Ni, Mn, and Al Containing Goethites by Mössbauer Spectroscopy

  • Jung Gi kim;Kim, Eng-Chan;Hwang, Hyeun-Gook;Hwang, Yong-Soon;V. I. Nikolaev
    • Journal of Magnetics
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    • 제2권4호
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    • pp.116-122
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    • 1997
  • To determine whether there is an ionic substitution of Ni, Co, Mn, and Al for Fe in synthetic goethites these materials have been studied by M$\ddot{o}$ssbauer spectroscopy at various temperatures ranging from 77 to 400 K. It is found that the presence of substituting elements in magnetically ordered structure of crystals may change the shape of M$\ddot{o}$ssbauer spectra of these caterials. The approximate distribution function of the effective magnetic field in the Fe nucleus p(Hn) is obtained from the M$\ddot{o}$ssbauer spectra. It is noted that the mean value of p(Hn) and its integral width can be taken as a measure of substitution in goethites.

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