• Title/Summary/Keyword: In-situ reaction

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Hybrid Solar Cells with Polymer/Fullerene Bulk Heterojunction Layers Containing in-situ Synthesized CdS Nanocrystals

  • Kwak, Eunjoo;Woo, Sungho;Kim, Hwajeong;Kim, Youngkyoo
    • Current Photovoltaic Research
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    • v.2 no.4
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    • pp.152-156
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    • 2014
  • We report hybrid solar cells fabricated with polymer/fullerene bulk heterojunction layers that contain inorganic nanocrystals synthesized by in-situ reaction in the presence of polymer chains. The inorganic (cadmium sulfide) nanocrystal ($CdS_{NC}$) was generated by the reaction of cadmium acetate and sulfur by varying the reaction time up to 30 min. The synthesized $CdS_{NC}$ showed a rectangular flake shape, while the size of $CdS_{NC}$ reached ca. 150 nm when the reaction time was 10 min. The performance of hybrid solar cells with $CdS_{NC}$ synthesized for 10 min was better than that of a control device, whereas poor performances were measured for other hybrid solar cells with $CdS_{NC}$ synthesized for more than 10 min.

In situ Photoacoustic Study of Water Gas Shift Reaction over Magnetite/Chromium Oxide and Copper/Zinc Oxide Catalysts

  • Byun, In-Sik;Choi, Ok-Lim;Choi, Joong-Gill;Lee, Sung-Han
    • Bulletin of the Korean Chemical Society
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    • v.23 no.11
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    • pp.1513-1518
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    • 2002
  • Kinetic studies on the water-gas shift reaction catalyzed by magnetite/chromium oxide and copper/zinc oxide were carried out by using an in situ photoacoustic spectroscopic technique. The reactions were performed in a closed-circulation reactor system using a differential photoacoustic cell at total pressure of 40 Torr in the temperature range of 100 to $350^{\circ}C.$ The CO2 photoacoustic signal varying with the concentration of CO2 during the catalytic reaction was recorded as a function of time. The time-resolved photoacoustic spectra obtained for the initial reaction stage provided precise data of CO2 formation rate. The apparent activation energies determined from the initial rates were 74.7 kJ/mol for the magnetite/chromium oxide catalyst and 50.9 kJ/mol for the copper/zinc oxide catalyst. To determine the reaction orders, partial pressures of CO(g) and H2O(g) in the reaction mixture were varied at a constant total pressure of 40 Torr with N2 buffer gas. For the magnetite/chromium oxide catalyst, the reaction orders with respect to CO and H2O were determined to be 0.93 and 0.18, respectively. For the copper/zinc oxide catalyst, the reaction orders with respect to CO and H2O were determined to be 0.79 and 0, respectively.

In-situ Synthesis and Investment Casting of Titanium Matrix (TiC+TiB) Hybrid Composites (Ti기 (TiC+TiB) 하이브리드 복합재료 반응생성합성 및 정밀주조)

  • Sung, Si-Young;Park, Keun-Chang;Lee, Sang-Hwa;Kim, Young-Jig
    • Journal of Korea Foundry Society
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    • v.24 no.3
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    • pp.159-164
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    • 2004
  • The aim of the present work is to investigate the possibility of in-situ synthesis and net-shape forming of the titanium matrix (TiC+TiB) hybrid composites using a casting route. From the scanning electron microscopy, electron probe micro-analyzer, X-ray diffraction and thermodynamic calculations, the spherical TiC and needle like TiB reinforced hybrid titanium matrix composites could be obtained in-situ by the conventional melting and casting route between titanium and $B_4C$. No melt-mold reaction occurred between the titanium matrix (TiC+TiB) hybrid composites and the SKK mold, since the mold is consisted with interstitial and substitutional metal-mold reaction products. Not only the sound in-situ synthesis but also the economic net-shape forming of the titanium matrix (TiC+TiB) hybrid composites could be possible by the conventional casting route.

Development of Diagnostic Techniques for Newcastle Disease in Chickens by In Situ RT-PCR and In Situ Hybridization (In situ RT-PCR 및 In situ hybridization 기법에 의한 닭 뉴캣슬병의 진단법 개발)

  • Park, Nam-Yong;Choi, Hyo-Im;Cho, Ho-Seong;Kang, Sung-Kwi;Cho, Kyoung-Oh;Brown, Corrie
    • Korean Journal of Veterinary Research
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    • v.42 no.3
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    • pp.351-362
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    • 2002
  • Newcastle disease (ND) is a highly contagious infection of poultry, Two pathology-based techniques, in situ RT-PCR and in situ hybridization (ISH) were applied to formalin-fixed, paraffin-embedded tissues from chickens naturally infected with velogenic ND virus (VNDV). Two pairs of primers and a probe for ISH and in situ RT-PCR, respectively, were selected from highly conserved region of matrix gene of NDV. The ISH experiment was carried out using MicroProbe$^{TM}$ capillary action system within 2 hours. In situ RT-PCR was performed using MicroProbe$^{TM}$ capillary action system and GeneAmp In Situ PCR system. With ISH and in situ RT-PCR, viral nucleic acid was detected in the central nervous system of chickens from infected with neurotropic velogenic Newcastle disease virus (NVNDV), whereas viral nucleic acid was detected in various organs or tissues of chickens from infected with viscerotropic velogenic Newcastle disease virus (VVNDV). In the NVND group, positive signals were characteristically defined in the cytoplasm of neuron, vascular endothelial cells, and perivascular mononuclear macrophages in the central nervous system. One of NVND group, chicken from one farm exhibited positive signals in the bronchial epithelium. The VVND group chickens showed positive reaction in the macrophages, vascular endothelium, and bronchiolar epithelium. Markedly, viral nucleic acid was detected in the macrophages of morphologically normal tissues which were peripheral or located in distant areas from lesions. The central nervous system of chickens infected with VVND virus had positive signals in the vascular endothelial cell, perivascular mononuclear macrophages and some neuron. The number and intensity of the positive cells by in situ RT-PCR were more and stronger, respectively, in comparison with those by ISH. Particularly, positive reaction was detected in macrophages infiltrating in cardiac muscle by in situ RT-PCR, but not obtained by ISH. Therefore, these results demonstrated that ISH is a rapid diagnostic method for detection of NDV and in situ RT-PCR can be used as an efficient method for detection of low viral load infection or subclinical viral infection of NDV.

In Situ X-ray Absorption Spectroscopic Study for α-MoO3 Electrode upon Discharge/Charge Reaction in Lithium Secondary Batteries

  • Kang, Joo-Hee;Paek, Seung-Min;Choy, Jin-Ho
    • Bulletin of the Korean Chemical Society
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    • v.31 no.12
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    • pp.3675-3678
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    • 2010
  • In-situ X-ray absorption spectroscopy (XAS) was used to elucidate the structural variation of $\alpha-MoO_3$ electrode upon discharge/charge reaction in a lithium ion battery. According to the XAS analysis, hexavalent Mo atoms in $\alpha-MoO_3$ framework are reduced as the amount of intercalated lithium ions increases. As lithium de-intercalation proceeds, most of pre-edge peaks are restored again. However, according to the Fourier transforms of the extended X-ray absorption fine structure (EXAFS) spectra, lithium de-intercalation reaction is partially irreversible upon the charge reaction, which is one of the main reasons why the capacity of $\alpha-MoO_3$ electrode decreases upon successive discharge/charge cycles.

Kinetic Study on the Cationic Polymerization of Glycidyl Azide Monomer(GAM) by Real-Time In-suti IR (실시간 In-situ IR을 이용한 Glycidyl Azide Monomer(GAM)의 양이온중합 반응속도 연구)

  • Kim, Hyoung-Sug;Kim, Kwan-Yung;Kang, Shin-Choon;Noh, Si-Tae;Kim, Jin-Seuk;Yu, Jae-Chul;Choi, Keun-Bae
    • Journal of the Korea Institute of Military Science and Technology
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    • v.12 no.2
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    • pp.228-235
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    • 2009
  • We synthesized glycidyl azide monomer(GAM) as a monomer for polymerization of glycidy azide polymer(GAP) which is a promising energetic prepolymer for a plastic-bonded explosive. Using quantitative real-tim in-situ infrared(in-situ IR) spectroscopy, kinetic study on the cationic ring opening polymerization of GAM was carried out. The reaction rate was obtained from monitoring the change of ether C-O stretching band($1050cm^{-1}$) in series IR spectra. The reaction was in accordance with the first-order reaction law for each of reaction temperature at 100/1 mole ratio of [GAM]/[$BF_3*etherate$]. In the ring opening polymerization of GAM, with ratio of [GAM]/[$BF_3*etherate$] to equal 100/1 at various temperature, the activation parameters obtained from the evaluation of kinetic data were ${\Delta}H^*$=14.34kcal/mol, ${\Delta}S^*=-12.31cal/mol{\cdot}K$ and $E_a$=14.89kcal/mol.

Effects of Processing Parameters on the Fabrication of in-situ Al/TiC Composites by Thermally Activated Combustion Reaction Process in an Aluminium Melt using Al-TiO2-C Powder Mixtures (알루미늄 용탕에서 Al-TiO2-C의 연소합성반응에 의한 in-situ Al/TiC 복합재료의 제조에 미치는 공정변수의 영향)

  • Kim, Hwa-Jung;Lee, Jung-Moo;Cho, Young-Hee;Kim, Jong-Jin;Kim, Su-Hyeon;Lee, Jae-Chul
    • Korean Journal of Metals and Materials
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    • v.50 no.9
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    • pp.677-684
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    • 2012
  • A feasible way to fabricate in-situ Al/TiC composites was investigated. An elemental mixture of $Al-TiO_2-C$ pellet was directly added into an Al melt at $800-920^{\circ}C$ to form TiC by self-combustion reaction. The addition of CuO initiates the self-combustion reaction to form TiC in $1-2{\mu}m$ at the melt temperature above $850^{\circ}C$. Besides the CuO addition, a diluent element of excess Al plays a significant role in the TiC formation by forming a precursor phase, $Al_3Ti$. Processing parameters such as CuO content, the amount of excess Al and the melt temperature, have affected the combustion reaction and formation of TiC, and their influences on the microstructures of in-situ Al/TiC composites are examined.

Evaluation of Several Parameters of in situ Polymerase Chain Reaction (ISPCR) to Reduce the Leakage of Amplificants from Cells

  • Lee, Jae-Yung;Auh, Chung-Kyoon;George W. Jordan
    • Journal of Microbiology
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    • v.40 no.1
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    • pp.70-76
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    • 2002
  • Proviral DNAs from HIV-1-infected CD4+ T cells (Molt/LAV cells) were amplified and detected in infected individual cells using polymerase chain reaction and in rifu hybridization. In this in situ PCR, three parameters were considered to achieve effective amplification and retention of amplificants inside the cells by making high molecular weight PCR products intracellularly, forming agarose matrix against the cells, and maintaining the appropriate PCR temperature profile. Over the cycles of ampliHcationl tailed primers with complementary overhanging sequences at their 5' sides manufactured high molecular weight products by using short primary products as a repeating unit. Agarose matrix could prevent the diffusion of the amplificants from the cells. Use of Thermanox coverslip inside the PCR tube offered target cells a similar temperature profile to that of conventional PCR in solution.